Chapter III
	Affected Environment and Environmental Consequences (Resources of Concern)
	This chapter describes affected resources, resources minimally affected, and resources largely unaffected or not impacted by the conversion of two long-term water service contracts.

Introduction

In this chapter, the resources described are those affected by conversion of the water service contracts. After the "Affected Resources" section, those resources determined to be minimally affected are described, including water quality, wildlife management, migratory birds, endangered species, and reservoir wetlands/riparian vegetation. Believed to be largely unaffected by contract conversion are Indian Trust Assets (ITAs), cultural resources, sacred sites, geology/soils, and environmental justice. The latter resources are discussed briefly.

Setting

The three Bureau of Reclamation (Reclamation) reservoirs in the Solomon River Basin (Basin) provide water for irrigation; municipal, industrial, and domestic use; flood control; recreation; and fish and wildlife resources. Fishing, hunting, and water-related recreation play an increasingly important part in the economy. Kirwin Reservoir provides recreational activities such as hunting, boating, swimming, fishing, picnicking, and bird watching. The area has 5,923 acres of land and 5,073 acres of water available for recreational use. Kirwin National Wildlife Refuge at Kirwin Reservoir provides for preservation of waterfowl, other animals, and plant life. Boating, swimming, water skiing, picnicking, fishing, and hunting are available at Webster Reservoir. The area has 2,733 acres of land and 3,766 acres of water available for recreational use. The available facilities along the shore of Waconda Lake and the large water surface area give many people the opportunity for camping, picnicking, sightseeing, water sports, hunting, and fishing. There are 13,890 acres of land and12,602 acres of water available for recreational activities.

Affected Resources

Water Resources

Overview

Affected Environment - Brief Summary

The analysis of water resources encompasses Kirwin and Webster Reservoirs, Waconda Lake, and the Basin.

Summary of Impacts

Water shortages would be approximately the same under the No Action and Irrigation Alternatives, but would be greater (up to about 9 percent in the Kirwin Unit) under the Fish, Wildlife, and Recreation Alternative (FWR Alternative).

Impacts Criteria

Impacts were evaluated using model-simulated average end-of-month (EOM) reservoir elevations and average annual percent irrigation shortages to irrigation districts.

Affected Environment

Inflows.--The water supply for the Kirwin Unit is provided by Project water directly out of Kirwin Reservoir via the Kirwin Canal. Kirwin Reservoir, in turn, is furnished by flows from the North Fork Solomon River and its major tributary, Bow Creek. The North Fork Solomon River originates in western Thomas County, approximately 120 miles west of Kirwin Dam, and drains an area of 1,373 square miles.

The Webster Unit is supplied water from Webster Reservoir via releases to the South Fork Solomon River and diversions to the Osborne Canal from the Woodston Diversion Dam located 16 miles downstream from the reservoir. Webster Reservoir receives its supply from the South Fork Solomon River, which originates 110 miles west of the dam and drains an area of 1,125 square miles.

Both the North Fork and South Fork Solomon Rivers derive their flows from precipitation runoff and groundwater discharge from underlying aquifers. The upper reaches of both basins overlie eastern portions of the High Plains Aquifer.

Since the mid-1960s, inflows to Kirwin and Webster Reservoirs have experienced significant declines, as illustrated in figure III-1 and III-2. The average annual inflow to Kirwin Reservoir has declined 29,000 acre-feet, from a 1920-64 average of 53,200 acre-feet to a 1965-99 average of 33,000 acre-feet. Webster Reservoir has experienced an annual average inflow decline of 41,000 acre-feet, from a 1945-64 average of 71,000 acre-feet down to a

Figure III-1.--Annual inflow to Kirwin Reservoir and deviation of precipitation
from average of 21.8 inches.

1965-99 annual inflow average of 30,000 acre-feet. During the 1990s, however, both reservoirs have registered a significant increase in inflows because of increased precipitation. The apparent trend in reduction of inflows could be the possible combination of several factors. Precipitation during the 1960s through 1980s was frequently below normal. There was also a dramatic increase in the development of groundwater irrigation systems in the watersheds above the dam (figures III-3 and III-4). Increasing groundwater withdrawals and less precipitation recharging the aquifers have probably resulted in reduced aquifer-to-stream contributions. Another factor potentially impacting streamflow is an increase in on-farm soil and moisture conservation practices which reduce runoff.

Waconda Lake is located downstream of the Kirwin and Webster Units at the confluence of the North and South Fork Solomon Rivers. Inflows to Waconda Lake are derived from releases to the river from Kirwin and Webster Reservoirs and from runoff and groundwater

Figure III-2.--Annual inflow to Webster Reservoir and deviation of
precipitation from average of 21.8 inches.

contributions from the intervening drainage area of 2,447 square miles. Included in these gains are any return flows from irrigation to the Kirwin and Webster Units. Inflows to

Figure III-3.--Annual Number of alluvial wells in North Fork Solomon River Basin
above Kirwin Reservoir.

Figure III-4.--Annual number of alluvial wells in South Fork Solomon River Basin
above Webster Reservoir.

Waconda Lake have not demonstrated quite the same dramatic declines as the two upstream reservoirs. The average annual inflow to Waconda Lake for 1968-99 was 220,400 acre-feet. Waconda Lake's inflows reflect less frequent spills from Kirwin and Webster Reservoirs and possibly reduced return flows from irrigation units.

Reservoirs.--Kirwin Reservoir's conservation pool of 89,639 acre-feet is between elevation 1697.0 feet and elevation 1729.25 feet. Added to the reservoir's inactive conservation and dead storage pools, total storage is 98,154 acre-feet.

Webster Reservoir has a conservation pool of 71,926 acre-feet between elevation 1860.0 feet and 1892.45 feet. Combined with the inactive conservation and dead pools, total storage is 76,157 acre-feet.

The reduced inflow to both reservoirs has resulted in a corresponding reduction in storage volumes since initial fillings (figures III-5 and III-6). Prior to 1993, the last time Webster

Figure III-5.--Kirwin Reservoir histroic May EOM content.

Figure III-6.--Webster Reservoir Historic May EOM content.

Reservoir filled to its capacity was in 1962. Kirwin Reservoir last filled to capacity in 1970 and did not fill again until 1993. For the period 1970-92, the average May end-of-month content was 22,000 acre-feet for Webster Reservoir and 34,000 acre-feet for Kirwin Reservoir.

Waconda Lake has a conservation pool of 204,789 acre-feet situated between elevation 1428.0 feet and 1455.6 feet. Combined with inactive conservation and dead pools, total storage is 241,460 acre-feet. Waconda Lake first filled in 1973 and has filled on a frequent basis since then (figure III-7). Annual demands for releases from Waconda Lake include a contract for up to 18,000 acre-feet of supplemental supply to Glen Elder Irrigation District, a 2,000 acre-foot contract for the City of Beloit, and a 1,009 acre-foot contract for Mitchell County Rural Water District No. 2. Additional releases from Waconda Lake are for administration of downstream water rights and water quality bypass releases for the City of Beloit as directed by the State of Kansas.

Figure III-7.--Waconda Lake historic May EOM content.

Irrigation Water Supply to Districts.--During the last two decades, reduced reservoir contents have resulted in less water available for delivery to the Kirwin and Webster Units. The Kirwin Unit under full development has the potential for irrigating 11,465 acres. Historically, an average of 6,900 acres have been irrigated with diversions from Kirwin Reservoir. In the 1980s and early 1990s, 5 years occurred during which no deliveries were made to the Kirwin Unit.

The Webster Unit has the potential for irrigating 8,537 acres under full development. Historically, an average of 4,332 acres have received deliveries from the Osborne Canal.

In the 1970s to early 1990s, 7 years occurred during which no canal deliveries were made.

The reduction in available supplies over the years has resulted in fewer deliveries to each acre irrigated (figures III-8 and III-9). For the Kirwin Unit, the average annual delivery per acre for 1957-79 was 16.5 inches, and for 1980-99 it was 11.2 inches. For the Webster Unit, the average annual delivery per acre for 1957-79 was 15.1 inches per acre, and for 1980-99 it was 10.3 inches. To conserve and better utilize reduced supplies in Kirwin and Webster Reservoirs, both districts have established a base annual diversion amount to the farmer of 12 inches per acre during water-short years.

Figure III-8.--Annual farm deliveries to the Kirwin Unit as inches per acre.

Methodology/Analysis

A monthly computer model of the Basin was developed to quantify the hydrologic impacts of alternatives evaluated for the contract renewal process. Model parameters that were targeted for use in evaluation of alternatives' impacts include streamflow, reservoir water

Figure III-9.--Annual farm deliveries to the Webster Unit as inches per acre.

supply, elevations, surface area, and shortages of irrigation demands. The model encompasses the entire Basin down to Niles, Kansas. It simulates the operations of the three Reclamation reservoirs, releasing water based on physical constraints and to meet Project and contractual demands.

A historical version of the model was developed first and was calibrated against historic conditions for the period 1960 to 1998. Comparisons and adjustments were made to get an acceptable simulation of historic reservoir EOM contents, reservoir releases, deliveries to irrigation units, and flows in streams.⁽¹⁾

The model uses a monthly time step to operate the system, starting with Kirwin and Webster Reservoirs, then moving down-basin to simulate Waconda Lake. Theoretical crop irrigation demands are calculated, then adjusted for on-farm efficiencies and conveyance system efficiencies to arrive at a canal headgate demand. For the Glen Elder Irrigation Unit, the model supplies natural flow from the Solomon River below Waconda Lake and delivers supplemental contractual water from Waconda Lake. Other demands incorporated into the model are for Mitchell County Rural Water District, the City of Beloit, and water quality releases from Waconda Lake. Monthly accounting of reservoirs is based on inflows, release demands, minimum and maximum storage contents, and reservoir evaporation.

Streamflow Adjustments to Present Levels.--The model is driven by the 1949-99 historic climatologic cycle. It is assumed that this cycle will repeat itself into the future for this analysis. Historic reservoir inflows were statistically adjusted to the 1993 level of Basin development to remove the historic general trend of declining streamflows. The resulting 1993-level flows represent what the historic water supply might have been if it had been depleted by the present-day level of water use practices in the Basin. It is further anticipated that future streamflows will not demonstrate any additional long-term declines beyond the 1993 level. Therefore, the 1993 level-of-development flows were used as input to the model to represent both present and future conditions.

Historic streamflows that were adjusted in the Basin to the 1993 level of development were inflows to Kirwin and Webster Reservoirs and reach gains above Waconda Lake. A comparison of annual average inflows of historic versus 1993-level flows follows:

Key Model Assumptions for Alternatives.--Following are selected key data used by the model to define the alternatives:

Impacts to water resources were evaluated using model-simulated average EOM reservoir elevations and average annual percent irrigation shortages to irrigation districts.

Impacts Analysis

The following graphs (figures III-10, III-11, and III-12) depict differences among average EOM elevations for the alternatives by reservoir. Historic average EOM elevations are also included to demonstrate past changes, many of which are attributable to reduced inflows to reservoirs.

For both reservoirs, the FWR Alternative results in EOM reservoir levels that are higher than the other alternatives as a direct effect of establishing higher minimum conservation pool elevations. EOM reservoir levels for the Irrigation and Negotiated Alternatives were relatively close to each other, as compared to the other alternatives. For Kirwin Reservoir, the Negotiated Alternative resulted generally in EOM levels slightly higher than those of the Irrigation Alternative. The opposite was true for Webster Reservoir, with the Irrigation Alternative resulting in slightly higher EOM levels compared to the Negotiated Alternative. The Irrigation Alternative results in generally higher EOM pools over the No Action Alternative due to reduced irrigation demands from the self-imposed 12-inch-per-acre restriction and from increased system efficiencies. The Negotiated Alternative would result in higher EOM levels over the No Action Alternative due to increased system efficiencies and the establishment of higher minimum conservation pool elevations.

Shortages are based on canal headgate delivery versus canal headgate demand. Canal head-gate demands are a product of crop irrigation requirements, on-farm efficiencies, and conveyance efficiencies. The crop irrigation requirements used for estimating shortages for all alternatives are the same as those used to model the No Action Alternative.

The Irrigation Alternative shows a slight improvement over the No Action Alternative scenario. This reflects the reduction in canal headgate demands due to the assumed increase in conveyance system on-farm efficiencies. The reduction in canal demands is offset somewhat by the self-imposed 12-inch-per-acre limit on farm deliveries, which has the effect of increasing shortages based on the crops' actual needs.

Although the FWR Alternative has the same demand assumptions as the Irrigation Alternative with regard to the 12-inch-per-acre limit, and the same increases in system efficiencies, it shows increased shortages over the No Action and Irrigation Alternatives. This is an effect of increasing the minimum elevation of conservation pools, thereby eliminating irrigation deliveries when levels drop below the minimum.

The Negotiated Alternative has the least shortage. The loss of available water supply due to raising minimum pools is offset by increased conveyance and on-farm efficiencies which reduce canal demands. It also has no 12-inch-per-acre limit which also reduces deliveries.

Figure III-10.--Kirwin Reservoir average EOM elevations comparison
(historic average of 1956-98; alternatives' average of 1949-98.)


Figure III-11.--Webster Reservoir average EOM elevations comparison
(historic average of 1957-98; alternatives' average of 1949-98.)


Figure III-12.--Waconda Lake average EOM elevations comparison
(historic average of 1968-98; alternatives' average of 1949-98.)

Net Impacts

Shortages to Irrigation Districts.--The following tables list average annual percent shortages and volume shortages for each alternative by irrigation district. The shortages reflect available water supply and, in some instances, delivery restrictions caused by canal capacity limits.

Socioeconomics

Overview

Affected Environment - Brief Summary

The analysis of social/economic conditions includes recreation, agriculture, and other resources in four counties where the affected resources are located--Osborne, Phillips, Rooks, and Smith in Kansas-- and in five additional counties in Kansas and two in Nebraska which have economic linkages to the four core counties.

Summary of Impacts

Among expected effects of the action alternatives are increases in reservoir recreation use, changes in cropping patterns, and overall increases in irrigation water delivery to crops, and, generally, in net farm income (all with some exceptions).

Impacts Criteria

Impacts were evaluated/projected by several criteria, including those based on changes in reservoir visitation and agricultural production, as explained below.

Introduction

Social and cultural values in the Basin are traditional, but they are inevitably changing because of technological and economic change. In general, while overall population has decreased, real per capita income has remained steady, indicating that household economic conditions have not deteriorated significantly for the remaining population.

The methods used to assess impacts in this section are based on (1) changes in reservoir visitation and expenditures and (2) changes in agricultural production which influence expenditures for production inputs and net farm revenues. Changes in recreation visitation are based on facilities availability and models of recreation visitation. Changes in agriculture-related spending are based on a farm economic budgeting model (attachment A).

Population.--There has been a consistent decline in the overall population. Between 1930 and 2000, the population of the region decreased from 116,792 to 77,708. The only counties that had a larger population in 1990 than in 1930 were Ellis and Thomas Counties in Kansas. These population changes are typical of many rural/agricultural areas in the Nation. As agriculture becomes more capital intensive, fewer jobs exist, and rural residents often migrate to urban areas in search of employment and higher education. No recent trends have counteracted this decline, as the population in the region decreased 7.9 percent between 1990 and 2000 (table III-2 and table III-3).

Income.--Total personal income in the region was $1.28 billion in 1990 (table III-4) and increased to $1.72 billion in 1998.

A total of 55,054 people were employed in the region in 1998, of whom 24.33 percent worked in the service sector and 12.74 percent worked in agriculture. The value of total output in the State of Kansas was $76,991 million, and in the State of Nebraska was $51,737 million in 1998 (current dollars). Farm income represents about 8.7 percent of total personal income in the study region.

Recreation.--Most of the land in the study area is in private ownership. Therefore, recreational activities associated with public facilities are mostly confined to areas adjacent to federally developed water projects. Recreation-based activities and associated businesses are generally concentrated around these reservoirs. These high-use areas are of economic significance- -especially to the individuals who operate campgrounds, marinas, bait shops, sporting goods stores, and related businesses. Recreation-based activities generate signifi-cant income and employment impacts in the region.

Agriculture.--Farming and ranching have been the primary economic forces in the area since the early 1800s (table III-4 and table III-5). The population has declined in tandem with the mechanization and modernization of agricultural methods. Fewer farmers and ranchers are needed to produce the same or higher yields and, as a result, corporate farms continue to challenge all but the most robust family farms. In 1992, approximately 14,000 farms in the Basin produced crops valued at about $2.57 billion.

Recreation

Affected Environment.--The Solomon River and its tributaries provide for a wide range of both reservoir and river-oriented recreation activities. Since the vast majority of visitation is associated with the reservoirs, the recreation analysis concentrates on the impacts to Kirwin Reservoir on the North Fork of the Solomon and Webster Reservoir on the South Fork of the Solomon Reservoir. Both of these structures were built by Reclamation.

The Kansas Department of Wildlife and Parks (KDWP) and the Fish and Wildlife Service (Service) manage the lands associated with Reclamation reservoirs in the Basin. Reclamation endorses their goals of providing diverse and quality outdoor recreation opportunities while protecting associated natural resources. Reclamation's goals, as landowner and resource steward, are to maintain public access to its reservoirs and associated lands and to operate them to sustain land- and water-based recreation.

The public use areas associated with the Solomon River reservoirs are considered valuable for recreation because so much of the land in this area of Kansas is privately owned and because manmade reservoirs represent a significant portion of the surface water in north-central Kansas. In addition, a substantial portion of public use recreation within the Basin occurs on reservoirs and the immediately adjacent lands, making recreation opportunities highly water dependent. Overall, recreation opportunities can be grouped mainly into water-based activities (i.e., fishing, boating, waterskiing, and swimming) and water-related activities (i.e., picnicking, sightseeing, hiking, and camping). As illustrated in table III-6, the Solomon River reservoirs include such water access features as boat-launching ramps, courtesy docks, and swimming beaches, as well as land-based but often water-oriented picnic and camping sites.

Although public use areas are typically open year round, many of the modern facilities are not available during the off-season. The main season for water-based reservoir recreation occurs between May and September, weather permitting. Winter season hunting and ice fishing also occur at the reservoirs.

Reservoirs.--The potentially affected Project area reservoirs include:

Webster Reservoir (Webster State Park and Wildlife Area).--Webster Reservoir is located in Rooks County in north-central Kansas on the South Fork Solomon River,approximately 72 miles west of the confluence of the North and South Forks of the Solomon River and 8 miles west of Stockton, Kansas. Highway 24 provides east-to-west access, and Highways 183 and 283 provide north-to-south access. Wildlife observation (primarily bird watching), warm water fishing, camping, motorized boating/waterskiing, swimming, and picnicking are the principal recreational activities at the park.

The Webster State Park and Wildlife Area includes the 3,800-acre reservoir and approxi-mately 5,500 acres of surrounding land. Access to the water is provided by four boat ramps and two designated swimming beaches. The park also offers nondesignated camping sites, camp pads, hookups, grills, picnic tables, shelters, and fishing docks.

Woodston Diversion Dam (Woodston State Wildlife Management Area).--The Woodston Diversion Dam is located on the South Fork of the Solomon River about1.5 miles west of Woodston, in Rooks County, Kansas, and about 16 miles downstream from Webster Dam. Since few recreational facilities exist at the Woodston Diversion Dam and Wildlife Management Area, recreation impacts were not evaluated for this site.

Kirwin Reservoir (Kirwin National Wildlife Refuge).--Kirwin Reservoir is located on the North Fork of the Solomon River just west of the town of Kirwin in Phillips County, Kansas. State Route 9 runs near Kirwin's north border, providing east-to-west access. Highway 183 provides north-to-south access. Wildlife observation, warm water fishing, camping and picnicking, hunting (primarily waterfowl), swimming, and motorized boating are the principal recreational activities at the refuge.

Kirwin National Wildlife Refuge includes the 5,079 surface acres of Kirwin Reservoir and5,749 acres of surrounding land. Access to the water is provided by four boat ramps. The refuge also offers multiple developed campsites, picnic tables, and group shelters. The Dane G. Hansen Boy Scout Camp is adjacent to the refuge.

Estimates of recent recreation use averaged across the 1994-2000 period for Kirwin National Wildlife Refuge, and across the 1990-2000 period for Webster State Park and Wildlife Refuge, are presented in table III-7. Total visitation for these primary activities averaged 98,728 at Kirwin and 192,889 at Webster. While these visitation estimates provide a reasonable reflection of current conditions, it should be noted that water levels during these periods were significantly higher than both historical conditions and the alternatives under consideration. For example, water levels at Kirwin Reservoir for the 1994-2000 period from April to September ranged from 1727.7 to 1731.8; this compares to a historical range of 1715.1 to 1718.2 and the No Action Alternative range of 1702.9 to 1705.5. Similarly, water levels at Webster Reservoir for the full year 1990-2000 period ranged from 1883.1 to 1886.6; this compares to a historical range of 1876.2 to 1880.1 and the No Action Alternative range of 1864.7 to 1868.5. As a result, visitation estimates for the various alternatives are much lower than those of current conditions.

Waconda Lake (Glen Elder State Park).--Waconda Lake is located on the mainstem of the Solomon River just west of the town of Glen Elder in Mitchell County, Kansas.

Highway 24 runs along the northern portion of the reservoir, providing east-to-west access. Impacts to Waconda Lake were determined by study management to be minor; therefore, the site was not included in the recreation analysis.

Methodology/Analysis.--The objective of the recreation analysis is to estimate changes in recreation visitation at Webster and Kirwin Reservoirs in north-central Kansas.

Attempts were made to model recreation use at both reservoirs, but, unfortunately, limited visitation data at Kirwin reduced the applicability of the estimated models. As a result, different approaches were used to evaluate visitation impacts at each reservoir. At Webster Reservoir, use estimation models were developed and applied in the estimation of visitation by alternative. At Kirwin Reservoir, a facility availability approach was used to generate visitation estimates by alternative. Both methods are fully detailed in attachment A.

Monthly data on visitation at Webster Reservoir by recreation activity from January 1980 to December 2000 was obtained from the reservoir manager. Recreation activities include camping, swimming, boating and waterskiing, picnicking, warm water fishing, and wildlife observation. Monthly information for the same time period was gathered on reservoir water levels, total monthly precipitation, and average monthly air temperature. Using this information, several statistical models were estimated to evaluate the relationship between recreation visitation by activity and water levels, total precipitation, and average air temperature. These models were used to predict visitation by activity at Webster Reservoir for each alternative based on the average monthly water levels predicted by Reclamation hydrologists.

The facility availability analysis used for Kirwin Reservoir forecasts recreation use by water- based activity through evaluation of changes in water access. The approach forecasts average monthly availability of water access facilities, such as boat ramps, marinas, and swimming beaches, using high- and low-end usability thresholds for each facility in conjunction with average EOM water level forecasts by alternative developed by Reclamation hydrologists. Table III-8 lists water access facilities and their respective high- and low-end water usability thresholds. Predicted monthly facility availability by alternative is combined with historical visitation information by activity, facility, and month to generate visitation estimates. Differences in predicted facility availability between alternatives lead to differences in predicted recreation visitation. Based on discussions with on-site recreation planners, impacts to both land-based and shoreline activities are expected to be minimal. As a result, the recreation analysis at Kirwin focuses on fishing and boating activities.

Impacts Analysis.--Due to the different methods used to determine impacts on recreation at each reservoir, results are presented separately for each reservoir.

Kirwin Reservoir and National Wildlife Refuge.--The results of the facilities availability analysis are presented in table III-9, table III-10, and table III-11.

There were no predicted changes in visitation at Kirwin Reservoir across the four alternatives. This is primarily due to a combination of two factors: first, the facilities availability method is less sensitive to changes in water levels compared to the use estimation model; second, based on the current high and low water level thresholds of the facilities, only the Rocky Flats boat ramp is expected to be available for all months and across all alternatives. On-site recreation planners suggest that the Rocky Flats ramp can only support about 50 percent of the historical visitation; a total of 14,077 visits per year are predicted for fishing, and 666 visits per year for boating. Table III-9 presents the monthly visitation estimates for both boat fishing and motorized boating, regardless of the alternative.

Table III-10 and table III-11 present details of the facility availability analysis separately for motorized boating and boat fishing. Each table indicates average monthly ramp availability under each alternative, EOM water levels by alternative, historic monthly visitation, and predicted percent of visitation by month and alternative.

Webster State Park and Wildlife Refuge.--Use estimation models were applied to predict changes in visitation by activity across the four alternatives. Forecasted average monthly water levels for each alternative were plugged into each use estimation model. The resultant monthly visitation estimates by activity were subsequently aggregated into annual visitation figures (see table III-12).

Webster State Park and Wildlife Area showed consistent increases in visitation as water levels increase across the three alternatives. The total change in visitation over the No Action Alternative is +13,642 visits (+15.4 percent) for the Negotiated Alternative, +20,397 visits (+23 percent) for the Irrigation Alternative, and +49,509 visits (+55.8 per-cent) for the FWR Alternative.

Mitigation/Other Environmental Measures.--Possible recreation mitigation could involve the construction of new boat ramps or the extension of existing ramps at Kirwin Reservoir in particular. Low-end usability thresholds in the 1,702- to 1,710-foot range would improve boat access, depending on the alternative.

Net Impacts.--Since the recreation analysis for Kirwin Reservoir shows no difference in visitation across alternatives, the entire recreation impact stems from changes in visitation at Webster Reservoir.

Agriculture

Affected Environment.--Kirwin and Webster Irrigation Districts (Districts) lie within the boundaries of four rural Kansas counties--Osborne, Phillips, Rooks, and Smith--with low population densities, accounting for less than 1 percent of the total population in the State of Kansas. The land area of the four counties makes up approximately 4.4 percent of the total land area for the State.

The agricultural industry has traditionally dominated the economic base and land use in the Basin. The number of farms in each of the four counties has declined from 2,449 in 1982 to 1,954 in 1997, a 20.2-percent decrease. Total acres in farms decreased from 2,134,133 acres to 2,121,424 acres from 1982 to 1997, a change of less than 1 percent. Given the relatively constant number of acres and the declining number of farms, it follows that the average size of farms has increased over the 1982-97 period. Irrigated acres increased from 16,805 acres to 25,598 acres from 1982 to 1997, a 52-percent increase (U.S. Department of Agriculture, 1982, 1992, and 1997). Trends in the Basin are shown in table III-13.

For the State of Kansas, the number of farms has decreased from 73,315 farms with 47.05 million acres to 61,593 farms with 48.09 million acres. This gives about a 16-percent decrease in the number of farms and a 2.2-percent increase in acres. There were 6,135 farms with irrigated acres, totaling 2.7 million acres.

Kirwin Irrigation District.--The major irrigated crops produced in the Kirwin Irrigation District are corn, alfalfa hay, and soybeans. Dryland crops produced include a wheat-sorghum-fallow rotation. Historical information about the size of the irrigation district is presented in table III-14, which also provides information about historical water deliveries for both a total and a per-acre basis. Table III-15 shows the acreages of the major crops for the last 5 years. Table III-16 shows the annual yields. These three tables give the annual values from 1995-99 and then the 5-year average.

Webster Irrigation District.--Most of the district lands are within Osborne County, where the major irrigated crops are corn, soybeans, and alfalfa hay. Dryland crops produced include a wheat-sorghum-fallow rotation. Historical information about the size of the irrigation district is presented in table III-17. This table also provides information about historical water deliveries for both a total and a per-acre basis. Table III-18 shows the acreages of the major crops for the last 5 years. Table III-19 shows the annual yields. These three tables give the annual values from 1995-99 and then the 5-year average.

Methodology/Analysis.--The analysis of farm-level economic impacts for the Districts used a Linear Programming (LP) model developed by Reclamation. The primary reason for using an LP model comes from the model's ability to simultaneously estimate farm-level impacts for multiple typical farms in a river basin.

Inclusion of desired sensitivity analyses is relatively quick and easy. After defining the base model, selected variables such as water supply can be altered to test the effects of changes in operating conditions.

Data obtained from the Districts' payment capacity studies were used in defining the model and included farm size, acres of each crop produced, crop yields, costs to produce each crop, and crop prices received. While the model uses data obtained from the payment capacity studies, it does not replicate these studies and cannot predict changes in payment capacity. The LP model is also described in attachment A.

Impacts Analysis.--Hydrology models prepared for the environmental assessment predict the changes in average annual water supply to the farms under each of the selected alternatives (No Action, Negotiated, Irrigation, and FWR). The LP model uses this information to estimate on-farm impacts. Estimates from the hydrology model provideinformation on the amount of irrigation water released from the dam, the carriage loss of water as it travels down the canal, and on-farm irrigation system efficiency. Subsequently, the actual amount of water available to the crops can be deduced.

For example, in the Kirwin Irrigation District under the No Action Alternative, the hydrology model estimated that total canal diversions averaged 12,401 acre-feet over the period of study. The average canal efficiency was 45 percent; thus, 5,580 acre-feet of water arrived at the farm headgate. Ultimately, after applying an irrigation system efficiency factor, 3,344 acre-feet of water was available to the crop.

When comparing the Irrigation Alternative to the No Action Alternative, less water (10,596 acre-feet) is diverted from Kirwin Reservoir. Additionally, there is a lower carriage loss and higher on-farm irrigation system efficiency. Subsequently, diverting the 10,596 acre-feet of water, assuming 62-percent delivery efficiency and an on-farm irrigation efficiency of 65 percent, provides 6,583 acre-feet delivered to the farm headgate and 4,280 acre-feet available for the crop. Compared to the No Action Alternative, the Irrigation Alternative provides 28 percent more water to crops. The benefits from the Irrigation Alternative are expressed as the increased efficiencies for delivering the water down the canal and on the farm.

When the No Action and FWR Alternatives are similarly compared, Kirwin Irrigation District has a 12.86-percent increase in crop water availability relative to the No Action Alternative. The Negotiated Alternative shows a 16-percent increase in water available to crops compared to the No Action Alternative.

Table III-20 shows the average diversions from the dam, amounts delivered to the farm headgate, and amount available to the crops for both the Districts. Also included is the baseline information from the 1995-99 period.

A decrease in irrigation water supply translates into fewer irrigated acres and a reduced net farm income. Cropping pattern adjustments include a substitution from irrigated dryland crop acres, keeping the overall farm size constant. Constraints imposed on the LP model include limiting the amount of change allowed to any one of the dryland crops to keep the model from simply choosing the most profitable dryland crop and putting all farm acres into that one crop. For example, as irrigated corn goes out of production due to decreased water supply, previously irrigated corn acres can go into dryland wheat, dryland sorghum, fallow land, or pasture. The LP model chooses which crop will increase or decrease its acreage, based on the relative profitability of the crops. Crops grown in a rotation, such as wheat-sorghum-fallow, must remain in that rotation scheme even through the relative acreages may vary.

Table III-21 shows the changes to cropping patterns given the change in water supplied to the crop. Under the Irrigation Alternative, irrigated corn acreage increases 62 percent relative to the No Action Alternative due to a larger water supply. Wheat acres decrease by 6 percent. On the Webster Irrigation District farm, irrigated corn acreage increases 36 per-cent relative to the No Action Alternative, while wheat decreases 4 percent and fallow land decreases 5.7 percent.

Under the FWR Alternative compared to the No Action Alternative, irrigated corn acreage increases 28 percent for the Kirwin Irrigation District farm. Wheat acres decrease about 3 percent. The Webster farm experiences a 19.5-percent reduction in irrigated corn acres, a 3.5-percent increase in wheat acres, and a 0.8-percent increase in fallow land.

The Negotiated Alternative provides 16 percent and 14.95 percent more irrigation water to crops than does the No Action Alternative for the Districts, respectively. Therefore, irrigated corn acreages increase 35.4 percent and 28.2 percent for the districts. The Kirwin Irrigation District has a decrease in dryland wheat acreage (3.6 percent) while Webster has an 11 percent decrease in dryland sorghum acreage.

In each of the alternatives, pasture acreage remains constant. By model definition, so do the number of unusable acres included in the typical farms. The driving force for these changes in cropping patterns comes from hydrology model assumptions about changes in delivery and on-farm efficiencies.

Changes in gross revenues, costs of production, and net farm income go hand in hand with the changes in cropping patterns. The LP model reports these changes for each of the alternatives. These changes reflect a net change in the farm's economic viability because both decreases in irrigated acres and increases in dryland acres are included, leaving the farm size constant. Table III-22 shows the changes to net farm income.

Income and Employment

Affected Environment.--Total personal income in the region was $1.28 billion in 1990 and increased to $1.77 billion in 1999 (foregoing table III-4), or $1.39 billion in 1999 dollars.

A total of 55,054 people were employed in the region in 1998, of whom 24.33 percent worked in the service sector, and 12.74 percent worked in agriculture. The value of total output in the State of Kansas was $76,991 million, and in the State of Nebraska was $51,737 million in 1998 (current dollars). Farm income represents about 8.7 percent of total personal income in the study region. Regional employment is shown in table III-23.

Methodology/Analysis.--

Recreation Impacts and Methodology/Analysis.--Recreation-related spending influences the regional economy through expenditures on food, gasoline, souvenirs, fishing supplies, and other goods and services that generate income and employment. ⁽²⁾ Average per-trip expenditures used in the analysis were $17.69 for fishing, $19.56 for motorized boating and water skiing, $13.59 for swimming, $15.06 for camping, $11.87 for swimming, and $13.51 for wildlife observation. These average figures were multiplied by the number of trips predicted for each reservoir, for each alternative, and for each activity. The resulting amounts are the total predicted amounts spent for each activity under each alternative.

Recreation expenditures only impact a region when the money spent would not have been spent inside the region except for the existence of the recreation site. That is, if anindividual would have spent the same money on another recreation site or on other activities within the region, then the money spent adds no new money into the region. Thus, in most cases it is assumed that if local residents participate in local recreation activities, the money they spend does not add to or impact the local economy. The opposite is also true: It is generally assumed that if a visitor to a recreation site comes from outside the economic region, he or she will spend money in the region that would otherwise not have been spent there. Effectively, an outside visitor adds new money into the region, thus impacting the region.

This being the case, it is important to identify the proportion of visitors that travel from inside and from outside the impact region. The counties included in the recreation region for estimating economic impacts are, in Kansas: Ellis, Graham, Norton, Osborne, Phillips, Rooks, Sheridan, Smith, and Thomas; and, in Nebraska: Franklin and Webster. Based on information provided by Webster State Park, the percentage of visitors from outside this region is approximately 35 percent of the total number of visitors to both reservoirs. Thus, the total amount spent for a recreation activity under each alternative is multiplied by 0.35 in order to determine the portion of the amount spent that will impact the region.

Agricultural Impacts and Methodology/Analysis.--Agribusiness-related spending affects the economy through purchases of crop production supplies and the generation of net farm revenue used to buy goods and services. The impacted agricultural region is defined as Osborne, Phillips, Rooks, and Smith counties in Kansas.

In order to estimate the regional impacts from changes in agricultural production associated with each alternative, the change in expenses and farm income derived from crop production must be estimated. Farm budgets developed by Reclamation were used to estimate the cost of crop inputs and net farm revenues for a representative farm under each alternative scenario. All the costs and revenues were translated into an equivalent per-irrigated-acre basis, and those costs and revenues were then applied to the changes in irrigated acreage for each alternative compared to the No Action Alternative.

Estimating the impacts from changes in farm income is not as straightforward as estimating the impacts from input expenditures because the types of goods purchased in the local area are not known. In order to estimate the regional impacts from net farm income, the pattern of spending collected under the name "household income, $20,000-$30,000" was chosen in IMPLAN (IMpact analysis for PLANing). ⁽³⁾ This group was chosen because it best reflected the median household incomes of the average farm in each irrigation district and for each alternative. This group of impacts reflects how $1 of the average household with an income between $20,000 and $30,000 is spent between all the goods and services available to the household.

Once these total spending patterns and amounts are determined, they are input into an IMPLAN model. To obtain the total regional economic impacts from changes in income in the agricultural analysis, the collection of impacts described as "Households, $20,000-$30,000" is multiplied by the number of dollars of income predicted under each alternative.

Analysis of Income and Employment Impacts (Recreation).--Table III-24 and table III-25 give the portion of the total amounts spent for each reservoir, by activity, expenditure item, and for each alternative that is predicted to impact the regional economy.

Using these figures, table III-26 lists the results of the IMPLAN analysis, indicating the change in regional impacts from each alternative compared to the No Action Alternative.

Net Income and Employment Impacts (Recreation).--Recreation under the Negotiated Alternative increases the region's:

• Total output by approximately $58,000
• Employment by 1.7 jobs
• Employment compensation by nearly $19,000
• Value of goods and services sold by $35,500

Under the Irrigation Alternative, recreation increases total regional output over the No Action Alternative by close to $83,000, increases regional employment by 2.5 jobs, increases regional employee compensation by roughly $28,500, and increases the value added of goods sold by the region by about $53,500. Under the FWR Alternative, recreation increases the region's total output over the No Action Alternative by a little more than $200,000, increases regional employment by six jobs, increases regional employee compensation by about $70,000, and increases the value added to goods sold by the region by approximately $131,000.

Analysis of Income and Employment Impacts (Agriculture).--Table III-27, table III-28, and table III-29 show changes in agricultural expenditures and farm income.

Net Income and Employment Impacts (Agriculture).--The three alternatives to No Action provide less irrigation water to the region's farms than the No Action Alternative. Despite this, only one alternative--the FWR Alternative--results in reduced output, employment, employee compensation, and value added to goods sold in the economy compared to the No Action Alternative. This results from expected increased efficiency of the farms under the circumstance of having reduced irrigation water available. Thus, under the Negotiated Alternative, output is projected to increase by almost $51,000, employment is projected to increase by 8/10 of a job, total wages are predicted to rise by slightly over $10,000, and the value added to goods sold is almost $25,500 over the No Action Alternative. For the Irrigation Alternative, output is expected to increase by almost $72,500, employment by more than one job, total wages by more than $14,000, and value added to goods sold by $33,000 more than the No Action Alternative.

For the FWR Alternative, the two irrigation districts have different projected responses to the decrease in irrigation water. Kirwin is expected to further increase its operating efficiency, while the Webster District is expected to be unable to increase efficiency beyond the efficiency seen in the Irrigation Alternative. Summing the results of these two effects results in slight decreases in the output, employment, total wages, and value added to the economy over the No Action Alternative. Thus, output under the FWR Alternative is expected to decrease by almost $1,800, employment would decrease by 1/10 of a job, total wages in the economy would decrease by slightly over $400, and the value added to goods sold would decrease by almost $850 over the No Action Alternative.

Resources Minimally Affected or Not Affected

Water Quality

Overview

Affected Environment - Brief Summary

The water quality analysis included the North and South Forks of the Solomon River from Kirwin and Webster Reservoirs downstream to the confluence of the two rivers.

Summary of Impacts

Project-induced impacts to water quality are believed to be negligible. Food chain bioaccumulation of selenium has not had documented effects on fish and wildlife, and a 2-year selenium study will be undertaken (chapter II).

Impacts Criteria

These included Environmental Protection Agency (EPA)-established water quality criteria for selenium and relationships to mean levels of constituents obtained by extensive sampling.

Affected Environment

North Fork of the Solomon River.--The surface waters in the basin of the North Fork of the Solomon River generally are turbid, even below Kirwin Dam and Reservoir, and generally have moderate to high concentrations of dissolved minerals. Water quality monitoring of the surface water in the North Fork has been performed by the U.S. Geological Survey (USGS) as early as 1961. The water quality results indicate that the North Fork has moderate to high concentrations of primarily total dissolved solids (tdS), sulfate, chloride, and calcium (high hardness). The elevated trace elements include primarily arsenic and selenium. tdS levels have varied from a mean value in the upper 600s milligrams per liter (mg/L) to maximum concentrations of over 1,200 mg/L. Sulfate levels have varied from a mean value in the 150s mg/L to over 220 mg/L. Chloride levels have varied from a mean value in the 40s mg/L to the mid 70s mg/L. The waters of the North Fork would generally be classed as very hard, with hardness levels ranging from the mid 300s mg/L level to over 700 mg/L. Other water quality parameters of interest include nutrients, levels of which are relatively low. Nitrate levels have always been below 5 mg/L, and nitrogen has a mean value of about 1.4 mg/L. Phosphate concentrations have also been low.

Irrigation is the primary use of water from the North Fork of the Solomon River between Kirwin Reservoir and the confluence with the South Fork. Irrigation runoff and return flows can have an adverse impact on the water quality conditions in the river. In addition, the presence of Kirwin Reservoir affects the natural water quality that would exist in the waters of the Basin. Kirwin Reservoir stores surface water from high runoff periods for later use as irrigation water below and east of the reservoir. Generally, the water quality parameters of concern relating to irrigation in the North Fork Basin are nutrients, arsenic, selenium, and possibly boron. The effect of irrigation in the basin is to accelerate the process of natural leaching of minerals and trace elements from the Niobrara and Pierre Shale geologic formations that are typical in this area of Kansas. Trace elements of most concern include selenium and arsenic. The water quality data indicate that both selenium and arsenic are ubiquitous in the Basin and are naturally occurring in the geologic formations. Selenium and arsenic levels have been measured in the same general concentration ranges and magnitudes.

The EPA has established a water quality criterion of 5 micrograms per liter (µg/L) to protect freshwater aquatic life from chronic levels of selenium (see the discussion of selenium in chapter II). Selenium doses exceeding twice the daily requirement for many birds, fish, and mammals may become toxic to an organism, lead to reproductive impairment, and/or cause birth defects. Further, selenium bioaccumulates within an organism, then biomagnifies through the food chain. Based upon monitoring by the USGS beginning in 1979, selenium concentrations in the North Fork have varied from a mean of about 7.5 µg/L to a high of about 14 µg/L, exceeding the criterion of 5 µg/L. In addition, arsenic concentrations have varied from a mean of about 9.1 µg/L to a high of about 20 µg/L. However, no cases of adverse effects on fish and wildlife have been documented over the last 40-plus years of irrigation in the basin. The fact that selenium and arsenic are both present in the tributaries and the main river is significant in that arsenic is antagonistic to selenium, and it is known that arsenic will negate the toxic effects of selenium in wildlife.

South Fork of the Solomon River.--The South Fork basin parallels and is physically similar to the North Fork basin. Webster Reservoir is located at the upper end of the irrigated lands, as is Kirwin Reservoir on the North Fork. The water quality conditions in the South Fork are generally quite similar to those of the North Fork. The concentration ranges and magnitudes of the common minerals and trace elements of interest in the South Fork are very similar to those of the North Fork. Based upon USGS monitoring in the basin, the concentrations of selenium in the South Fork have varied from a mean of about 7.5 µg/L to a maximum of about 33 µg/L. Also, the concentrations of arsenic have varied from a mean of about 8 µg/L to a maximum of about 70 µg/L.

Like the North Fork, the primary use of water from the South Fork of the Solomon River below Webster Reservoir is irrigation, and irrigation use can have an adverse effect on water quality.

Methodology/Analysis

In 1994, the Service conducted a contaminants evaluation of the Solomon River drainage in Kansas. Water samples were collected at 12 locations for 5 times from spring to early fall and analyzed with field test kits. Of the 12 sample locations, only 4 were between Kirwin and Webster Reservoirs and Glen Elder Reservoir (the irrigated agricultural areas within this current study area). The samples were analyzed for some agricultural chemicals commonly used in Kansas: organophosphates, carbamates, and thiophosphates; 2,4-D and related compounds; triazines; alachlor compounds; and petroleum compounds. Also, ceriodaphnia bioassays were conducted in May and September to screen water samples for a toxic response. And, finally, sediments and fish were analyzed for metals, organochlorines, and petroleum compounds. The results of this study are summarized as follows:

• Low concentrations of the groups of agricultural chemicals and petroleum compounds were detected in surface water analyzed with the field kits. None of the groups of compounds was detected at levels that could cause direct mortality to fish and wildlife.
• Toxicity in some of the bioassays indicated that there were episodes of poor water quality in the basin. More comprehensive water monitoring would be required to determine the causes of toxicity to aquatic biota.
• Concentrations of most metals in sediments were low to normal.
• Some fish samples contained detectable concentrations of cadmium, mercury, and selenium. However, the concentrations were not high or were at concentrations unlikely to affect the fish.
• Chlorinated hydrocarbons were not found in sediments, and the concentrations in fish were very low.
• Aliphatic and aromatic petroleum hydrocarbon analysis indicated that there was little petroleum contamination of the waters in the basin.

Reclamation initiated additional water quality monitoring in 1996 as part of the water service contract renewal process. A few water quality samples were collected in 1996, and extensive area monitoring was performed in 1998 in both the North Fork and South Fork of the Solomon River from the reservoirs downstream to the confluence of the two rivers. The parameters of most interest in the water quality monitoring program were selenium and arsenic. Arsenic was the focus, not because of its potential hazards, but because of its antagonistic effects on selenium. Other parameters included in the monitoring work in 1998 included major cations and anions, nitrate, tdS, hardness, boron, and streamflows. Some additional metal tests were conducted, and water samples were collected at a few specific locations on the two rivers for pesticide analysis. Biota sampling also was performed on both the North and South Forks of the Solomon River.

North Fork of Solomon River, 1998 Monitoring.--Within the North Fork basin, water quality samples were collected at 21 sites from Kirwin Reservoir to Portis on two different occasions during the year, May 20, 1998, and August 25, 1998. One site was at the reservoir, 4 sites were on the North Fork River, and 16 sites were on tributaries and irrigation drains that discharge into the river. Three additional tributary sites were initially proposed for sampling, but they were dry on both sampling dates in 1998. The tributaries, which drained both natural and irrigated lands, were sampled both above the irrigated area and at the point of discharge into the river. The monitoring sites were selected to determine the impacts of return flows from agricultural irrigation on the water quality in the tributaries and drains and subsequently on the river. Sediment samples were collected in 1998 on the North Fork (attachment B). One site was on the river above Kirwin Reservoir and the other four sites were below the dam.

South Fork of Solomon River, 1998 Monitoring.--Within the South Fork basin, water quality samples were collected at 19 sites from Webster Reservoir to near Osborne, Kansas, on two different occasions during the year, May 20, 1998, and August 25, 1998. One site was at the reservoir, 5 sites were on the South Fork, and 13 sites were on tributaries and irrigation drains that discharge into the river. Three additional tributary sites were initially proposed for sampling, but they were dry on both sampling dates in 1998. The tributaries, which drained both natural and irrigated lands, were sampled both above the irrigated area and at the point of discharge into the river. The monitoring sites were selected to determine the impacts of return flows from agricultural irrigation on the water quality in the tributaries and drains and subsequently on the river. Sediment samples at five sites were collected (attachment B) at Webster Reservoir and four sites below the dam.

Impacts Analysis

North Fork.--The following summarizes the water quality data results for selected parameters for the two 1998 sampling episodes: table III-30 and table III-31.

The above data indicate that the contribution of selenium to the North Fork of the Solomon River is considerable in the natural tributaries, and the range is similar to the selenium con-centrations in the tributary and drain flows into the river which are impacted by irrigation. However, the irrigation-impacted tributaries, in general, show selenium concentrations are less than in the natural tributaries or tributaries above irrigated lands. This conclusion is expected when considering that the irrigated lands have been irrigated for over 40 years and more selenium has been leached from the agricultural area soils that the soils in the nonirrigated areas of the Basin. A selenium load analysis was performed to further determine the impacts of irrigation on the selenium loads discharged to the river. The following summarizes the results of the load analysis using the selenium concentration data and streamflows for the monitoring periods in 1998.

The load data from the selenium load analysis show that the natural tributaries not affected by irrigation and the tributaries upstream of irrigated lands draining nonirrigated lands contribute more selenium to the river than the drainage from irrigated lands on a selenium load basis. This is particularly evident when comparing the unit selenium load data shown above; however, the unit selenium load for natural tributaries is less than from irrigated areasfor the May 19, 1998, monitoring period. The water samples occurred before irrigation began, and the selenium loads from irrigated areas are probably more reflective of the natural selenium load from nonirrigation-impacted lands in these tributary basins.

Two water samples were collected from the one irrigation pipe drain (site KWD) located within the North Fork basin and analyzed for pesticides. One sample was collected in the summer of 1996, and a second sample was collected in the summer of 1998. No pesticide analyte was detected for either water sample.

The sediment sample results generally indicate concentrations that are within typical ranges in the western part of the country. Selenium concentrations were somewhat elevated, but there did not appear to be any consistency in the results. In moving downstream from Kirwin Reservoir, there was not a clear increase in concentration that would indicate increased loading from irrigation activities. The selenium concentration at the site above Kirwin Reservoir was actually slightly higher than the North Fork at Portis (a selenium concentration of 1.2 µg/L was compared with a selenium concentration of 1.1 µg/L at Portis).

South Fork.--Table III-32 summarizes the water quality data results for selected parameters for the two 1998 sampling episodes in the South Fork.

The data indicate that the contribution of selenium to the South Fork of the Solomon River is considerable in the natural tributaries, and the range is similar to selenium concentrations in the tributary and drain flows into the river which are impacted by irrigation. However, the two irrigation-impacted tributaries have selenium concentrations that are slightly greater than in the natural tributaries or tributaries above irrigated lands. A selenium load analysis was performed to further determine the impacts of irrigation on the selenium loads discharged to the river. Table III-33 summarizes the results of the load analysis using the selenium concentration data and streamflows for the monitoring periods in 1998.

The selenium load analysis shows that the natural tributaries not affected by irrigation and the tributaries upstream of irrigated lands draining nonirrigated lands contribute more or less selenium to the river depending upon the time of year, as indicated above. However, when comparing the unit selenium load data, the selenium loads for the irrigated areas are less than the unit selenium loads for the natural tributaries not affected by irrigation.

Two water samples were collected from the irrigation pipe drain and analyzed for pesticides. One sample was collected in the summer of 1996, and a second sample was collected in the summer of 1998. No pesticide analyte was detected for either water sample.

The sediment sample results generally indicate parameter concentrations that are within typical ranges in the western part of the country. Selenium concentrations were somewhat elevated, but there did not appear to be any consistency in the results. In moving downstream from Webster Reservoir, there was not a clear increase in concentration that would indicate increased loading from irrigation activities. The selenium concentration at the site above Webster Reservoir was actually higher than the South Fork at Osborne (a selenium concentration of 1.3 µg/L as compared with a selenium concentration of 0.6 µg/L at Osborne).

Solomon River Basin Biota Sampling.--Between July and September 1998, a total of 20 samples of invertebrates and 195 fish samples were collected for selenium analysis. For the invertebrate samples, the selenium concentration (micrograms per gram [µg/g] dry weight) values ranged from 4.64 to 18.2 µg/g, with a mean concentration of 11.1 µg/g. All invertebrate samples contained selenium concentrations that exceeded 3 µg/g. The dietary toxicity threshold of selenium invertebrates for fish and wildlife has been reported to be 3 µg/g (Lemly, 1993). The invertebrate data from the Basin (both the North and South Forks of the Solomon River) indicate evidence of food chain bioaccumulation of selenium. For the fish samples (195 samples), the selenium concentration values ranged from 2.68 to 16.4 µg/g, with a mean concentration of 9.5 µg/g. Ninety-seven percent of the samples (189 samples) had selenium concentrations that exceeded 4 µg/g. The whole body biological effects threshold of selenium concentration (µg/g dry weight) for the health and reproductive success of freshwater fish has been reported to be 4 µg/g (Lemly, 1993). Again, the fish data from the Basin (both the North and South Forks of the Solomon River) indicate evidence of food chain bioaccumulation of selenium.

Mitigation/Other Environmental Measures

"Adaptive Management Process and Selenium Concentrations" (in chapter II).

Net Impacts

The fact that selenium effects on fish or wildlife have not been found and documented probably lends to the theory that, because of the presence of arsenic in the soils and water in the Basin, the toxicity of selenium is apparently negated. It is known that arsenic and selenium are antagonistic to one another and they negate the toxicity of each other when both are found in the environment. A 2-year selenium study will be undertaken to determine food chain bioaccumulation effects of selenium on fish and wildlife.

Wildlife Management

River and Reservoir Fisheries and Riverine Wetlands

The Solomon River, including Kirwin and Webster Reservoirs and Waconda Lake and the surrounding public and project irrigated lands, are inhabited by a wide variety of terrestrial, avian, and amphibian wildlife common to the Great Plains. This assemblage of wildlife, especially those species of economic importance or managed at Kirwin National Wildlife Refuge, were of concern to the public that attended meetings on contract renewal.

Overview

Affected Environment - Brief Summary

This analysis of the management of wildlife encompasses the Solomon River, the three Project area reservoirs, and the surrounding public and Project irrigated lands.

Summary of Impacts

None of the alternatives would change existing riverine or reservoir fisheries or riverine wetlands.

Impacts Criteria

For fisheries, criteria included surface acreage, volume, and flow; for riverine wetlands, criteria included average monthly reservoir releases.

River and Reservoir Fisheries.--

Affected Environment.--Reservoir and stream fisheries are significant issues in contract renewal, according to the KDWP, which manages the State's fisheries, and the general public, who see reservoir fisheries as key to the recreation economy. They are concerned that fisheries are unsustainable if reservoir pools are drawn down to a level where shallow water habitats (littoral zone) are dewatered and the reservoir's volume is significantly diminished. The public is also concerned that groundwater pumping is adversely impacting fisheries and should be restricted. Groundwater pumping, combined with below-average precipitation, diversions, terracing, farm ponds, and other on-farm moisture retention practices, has reduced surface water, resulting in less habitat for fishes and other aquatic resources.

In a historical perspective, the riverine ecology of the Solomon River has changed sig-nificantly since European settlement and, with it, the composition and abundance of fish. The native species evolved under extremes of drought and floods characteristic of rivers in the American Great Plains. Only those species that could tolerate and reproduce under wide ranges of temperature, dissolved oxygen, current velocity, discharge, and water quality survived. With the advent of dams, these extremes were moderated, providing an opportunity for less resilient species to inhabit the river and its impoundments. The impoundments provided slackwater habitat that did not previously occur and altered the flow patterns of the river. Riverine hydrology changed from floodflows in the spring and low flows or ponding in the summer and fall to reservoirs holding water in the spring and releasing it throughout the summer and fall to accommodate irrigation needs. There is no better example of how these changes impacted aquatic resources than the fish fauna. Native species like the plains killifish, fathead minnow, creek chub, black bullhead, red shiner, and white sucker are very resilient to extreme conditions but are not competitive for space, food, and survival with non-native species like the walleye, largemouth bass, and white bass, which cannot survive under extreme conditions. Sport fish and other non-native fish flourished in the impoundments, and management for sport fish has altered streamflows at the expense of native species that, in some cases, have been extirpated.

In recent years, a decrease in water reaching the river has become the greatest threat to aquatic resources. Diversions, groundwater pumping, on-farm moisture retention practices, upstream irrigation development, and below-average precipitation in the Solomon River watershed have resulted in a significant decline in the inflows to all reservoirs. Reservoir levels are lower, and less water is available for release during the nonirrigation season (late fall, winter, and spring). Streamflows below the reservoirs are rarely sustainable and come from periodic spills, seepage, and irrigation return flows. Aquatic habitat in both reservoirs and in the river has declined with the surface water supply.

Webster Reservoir Fishery.--The KDWP, which manages the Webster Reservoir fishery, reported in 1977, that "...Walleye, white crappie and channel catfish are found in abundant numbers and quality sizes. Flathead catfish and striped bass are the trophy fish of the lake, and both species are plentiful" (KDWP, 1977; KDWP, personal communication, 2000). Today, the fishery has a variety of native and non-native sport and forage fishes with emphasis placed on the management of walleye, wiper (white bass x striped bass hybrids), largemouth and smallmouth bass, and black and white crappie (KDWP, 2000). The highest priority for the State is to

"...create a fish, wildlife, and recreation pool to eliminate irrigation drawdowns to elevations lower than 1866.0 mean sea level and to avoid evacuating in excess of 45 percent of the total reservoir contents (KDWP, 2000). This will provide enough water to maintain water quality, avoid fish losses through the dam (entrainment), and allow the establishment of shallow water (littoral zone) vegetation for spawning, forage and rearing habitats."

Kirwin Reservoir Fishery.--The KDWP also manages the fishery at Kirwin Reservoir. Kirwin Reservoir has been cited as an excellent fishery for walleye, white and black crappie, white bass, channel catfish, and flathead catfish, though underutilized by anglers (KDWP, 1977). As with Webster Reservoir, Kirwin Reservoir has a variety of native and non-native sport and forage fishes and emphasizes the management of walleye, wiper (white bass x striped bass hybrids), largemouth, and crappie (KDWP, 2000). Maintaining a pool elevation high enough to sustain the fishery is a prime concern. A formal request for a minimum pool elevation of 1702.0 was submitted to Reclamation by the KDWP in October 2000 for consideration as a condition in future irrigation contracts. The Service has also requested a minimum pool for the reservoir at elevation 1703.6 MSL.

Waconda Lake Fishery.--The third lake in the Basin is Waconda Lake (sometimes termed Glen Elder Reservoir locally). It has a mix of native and non-native sport and forage fishes similar to that of Kirwin and Webster Reservoirs but its location lower in the Basin and low irrigation demands have kept its pool elevations more stable. It, too, is managed by the KDWP for walleye, white bass, channel catfish, and black bass (KDWP, 2000). No minimum pools were recommended by the KDWP or the Service.

River Fisheries.--Human intervention, by way of agriculture and species introductions, has significantly changed the river's fish populations and species composition (Service, 1979). The existing fisheries and water management practices favor non-native species and water retention in reservoirs over natives and riverine flows, as described above. The river and its tributaries do remain important as spawning habitat for economically important reservoir fishes, as a food source for wildlife along the river corridor, and as a refugia for native fishes. The fishery habitats, uniform throughout the Basin, are composed of a smooth, flat channel with sand, silt, and gravel substrate and periodic pools caused by beaver dams and scouring around debris. Flows are most consistent seasonally and interannually below the dams because of seepage, irrigation return flows, and reservoir releases.

Methodology/Analysis.--This analysis compares fisheries habitat for each of the three alternatives in terms of surface acreage and flow and uses KDWP reports and personal communications to assess the impact of contract renewal on fisheries.

Flow and reservoir volume data were modeled for years 1949-98 to simulate the effects of the historic conditions and the No Action, Irrigation, Negotiated, and FWR Alternatives. The FWR Alternative is the most beneficial to reservoir fisheries at Kirwin and Webster Reservoirs because it maintains the highest pool elevation in all months, providing the greatest littoral zone for fish habitat. This is not surprising since the FWR Alternative was designed for this purpose. However, what is noteworthy is the small difference (less than 1.75 percent) in surface acreage among the alternatives at each reservoir. Given the imprecision of the data (i.e., flow data +/- 10 percent, bathymetry inaccuracies, and the use of EOM averages with large variability), this analysis considers the surface elevation data for the No Action, Irrigation, Negotiated, and FWR Alternatives to be statistically indistinguish-able at each reservoir.

At Waconda Lake, the Irrigation Alternative has higher pools than the FWR Alternative. This difference from the other two reservoirs is unexplainable, but, because of the reasons given above, the differences are statistically indistinguishable. The Irrigation, Negotiated, and FWR Alternatives are essentially the same.

Impacts Analysis.--None of the alternatives would significantly change the riverine fisheries. This conclusion is based on the statistical "sameness" of the alternatives and the infrequency of releases. The releases for each alternative for a specific reservoir include small differences, but these data have inherent inaccuracies because of modeling assumptions and the sensitivity of the flow measurements. The alternatives at each reservoir are statistically alike. The infrequency of releases is the second point of the analysis. The capture and retention of water in the reservoirs is a priority for irrigation, reservoir fisheries, and recreation. Releases which "waste" water are made only for flood control or dam safety or because of exceeding the reservoir's storage capacity. These situations are avoided to prevent the loss of water, and they rarely occur because of drought, groundwater pumping, and water retention practices in the surrounding watershed. Spills are so infrequent that they cannot be counted on to provide spawning and rearing habitat often enough to significantly change populations or species composition.

Riverine Wetlands.--

Affected Environment.--Riverine wetlands are important for their wildlife habitat, flood attenuation capabilities, erosion control, and water filtration qualities. They are composed of grasses and forbs in the more arid headwater areas, to evolving communities of cottonwood, willow, green ash, burr oak, American elm, and hackberry in moister, lower reaches. In the Great Plains, where forests are rare, they offer cover, forage, and breeding habitat for neotropical migratory birds and aquatic species. Riverine wetlands downstream of Kirwin and Webster Reservoirs and Waconda Lake could be impacted by changes in reservoir releases; therefore, this analysis is an indication of the way in which wetland protection laws would be impacted by contract renewal.

Methodology/Analysis.--The volume, frequency, and pattern of reservoir releases could change the size and vegetation of these wetlands and thereby impact their habitat, flood control, and water quality properties. Average, monthly reservoir releases are used as an indicator for riverine wetland impacts; the more these releases mimic the preimpound-ment hydrology and greater the probability of releases, the better for maintaining wetland values.

Impacts Analysis.--The No Action Alternative assumes a succession toward more mesic species such as oak, elm, juniper, and Russian olive. This is not the most favorable condition for habitat and flood control properties, but it is the most likely condition given the absence of floods that broaden the flood plain, set back plant succession, and encourage more diverse habitats. The development of irrigation and flood-control impoundments has reduced floodflows and promoted narrower, unbraided channels and denser vegetation.

None of the alternatives would significantly change the size or vegetation of the riverine wetlands. This conclusion was reached because all three are statistically indistinguishable, and the frequency of reservoir releases is so rare that it is unlikely to impact the vegetation in the riparian wetlands. The modeling of releases from all three reservoirs shows small differences among the alternatives, but these data have inherent inaccuracies because of the modeling assumptions and the sensitivity of the flow measurements; therefore, the differences among the alternatives at a single reservoir can be lost in the insensitivity of the data. The second issue is infrequency of releases. The capture and retention of water in the reservoirs is a priority for irrigation, reservoir fisheries, and recreation. Releases are made to the river below the dams only for flood control, dam safety, or exceeding the reservoir's storage capacity. These situations are avoided to curb the loss of water, and they rarely occur because of drought, groundwater pumping, and water retention practices in the surrounding watershed. Spills are so infrequent that they cannot be counted on to set back plant succession, broaden the flood plain, or change the plant community along the river.

Mitigation/Other Environmental Measures for Wildlife Management.--Because no adverse effects are anticipated under any of the alternatives, no mitigation is required.

Net Impacts - Wildlife Management.--The action alternatives produce impacts similar to those of the No Action Alternative. Accordingly, no net impacts to wildlife are anticipated.

Migratory Birds

Executive Order 13186 requires Federal agencies to consider the effects of their programs, policies, and activities on migratory birds.

Overview

Affected Environment - Brief Summary

The analysis includes waterfowl, shorebirds, wading birds, and neotropical birds inhabiting or migrating through the reservoir riverine area in the Basin.

Summary of Impacts

No net adverse impacts would occur for tree-, shrub-, or grassland-nesting birds, and there would be a net beneficial effect for migratory water birds.

Impacts Criteria

Impacts were based on data covering reservoir operations, ecological responses of vegetation communities, and the ecological requirement of migratory birds.

Affected Environment

Migratory Waterbirds.--The Basin is located within the Central Flyway and provides important habitat for migrating waterfowl, shorebirds, wading birds, and neotropical migratory birds. Waterbirds migrating through the Basin use natural and managed wetlands for forage and loafing habitat, forage waste grain from agricultural areas, and use waterbodies like Kirwin and Webster Reservoirs and Waconda Lake for sanctuary, foraging, and loafing.

Common migratory waterbirds include mallards; teal; shovelers; scaup; coots; Canada, white-fronted, and snow geese; herons; egrets; sandpipers; phalaropes; gulls; terns; cormorants; and sandhill and whooping cranes. As many as 70,000 Canada geese, 40,000 white-fronted geese, and 220,000 ducks may use Kirwin Reservoir annually (Service, 1996), while Waconda Lake annually receives moderate to heavy waterfowl use with peaks of over 100,000 Canada, white-fronted, and snow geese and 100,000 ducks (KDWP, 1996).

Depending on climatic conditions, many Canada geese and ducks, mainly mallards, stay through the winter. Ideal conditions develop for some waterfowl species when reservoirs inundate trees killed by high water in 1993 and 1995. Double-crested cormorant and great blue heron rookeries are located at the west end of Kirwin Reservoir.

Neotropical Migratory Birds.--These birds, migrating through or breeding in the Basin, include meadowlarks, swallows, wrens, robin, vireos, sparrows, blackbirds, flycatchers, kingbirds, and warblers. Riparian vegetation found along waterways and at Kirwin and Webster Reservoirs and Waconda Lake provides important foraging, roosting, nesting, and brood-rearing habitat for migrating songbirds. In 1993 and 1995, inundation of much of this riparian vegetation occurred at the impoundments, and large tracts of reservoir riparian vegetation were lost. Approximately 350 acres remain at Kirwin Reservoir (Service, 1996) while approximately 1,500 acres remain at Webster Reservoir (Zajic, 2001). These flood events killed all but about 400 acres of reservoir riparian vegetation and other woodlands at Waconda Lake (KDWP, 1996). Not all of the mature reservoir riparian vegetation was lost, and regeneration of wetlands and riparian vegetation around the reservoirs is ongoing. Grassland habitats adjacent to the reservoirs provide important foraging, roosting, nesting, and brood-rearing habitat for ground-nesting species.

Other Migratory Birds.--These birds include bald and golden eagles, hawks, osprey, and falcons. The Service (1996) reports that 25 raptor species are associated with Kirwin National Wildlife Refuge, with confirmed nesters including red-tailed and Swainson's hawks and barn, screech, great-horned, and burrowing owls. Nonmigratory birds, such as turkeys, pheasant, quail, and greater prairie chicken are widespread and associated with agricultural lands, shelterbelts, and grasslands.

Reservoir Habitat.--Over the period of record (1949-98) for Kirwin Reservoir, the surface area averaged 3,004 acres during fall (September - October)--the season most important for migratory waterfowl. Webster Reservoir averaged 2,183 acres during the same period. During fall for the period of record for Waconda Lake (1967-98), the average reservoir surface area averaged 11,030 acres.

Methodology/Analysis

The overall composition of habitat types was obtained from existing reservoir (KDWP, 1996) and refuge management plans (Service, 1996). Hydrologic data were derived from hydrology model output. The analysis of impacts was based on an understanding of reservoir operations, ecological responses of pioneer and riparian vegetation communities, and the ecological requirements of migratory birds.

Impacts Analysis

No Action Alternative .--Declining inflows, on-farm soil and moisture conservation practices, and other water use and conservation activities have reduced average reservoir surface areas at Kirwin and Webster Reservoirs during fall when compared to the average reservoir surface area during the period of record. These activities and climatic conditions have reduced average surface areas of these reservoirs, and the reduction would persist under the No Action Alternative. During fall, the average surface area of Kirwin Reservoir is reduced to 1,642 acres, or a reduction of 45 percent compared to existing conditions. The average surface area of Webster Reservoir is reduced to 1,278 acres, or a reduction of 41 percent compared to existing conditions. Such reductions are significant and limit the availability of loafing and refuge habitat for migratory waterbirds. The average surface area of Waconda Lake during fall increases to 11,416 acres, or an increase of 3 percent compared to existing conditions.

Reservoir riparian habitat used by neotropical migratory birds is expected to continue to cycle through periods of inundation and death and lower surface elevations and expansion. Inundation most recently occurred at the impoundments in 1993 and 1995. This flooding killed all but about 400 acres of reservoir riparian vegetation and other woodlands at Waconda Lake (KDWP, 1996), all but about 1,500 acres at Webster Reservoir (Zajic, 2001), and all but about 350 acres at Kirwin Reservoir (Service, 1996).

Regeneration of wetland and riparian vegetation around the reservoirs is ongoing. Death of some of the elm and cottonwood trees will reduce foraging and nesting habitat for species adapted to tree canopies. These species must locate suitable alternative habitat in the immediate area or migrate further north. Cavity-nesting birds and other species adapted to dead trees and snags would benefit. Available habitat for great blue heron and double-crested cormorant rookeries would not change. Shrub-nesting birds would be affected more often by the effects of inundation and habitat modification; however, shrub habitats would regenerate more quickly than trees. Grassland-nesting birds would not be affected by reservoir fluctuations.

Irrigation Alternative.--This alternative would increase the average reservoir surface area during fall by 134 acres at Kirwin Reservoir, 306 acres at Webster Reservoir, and 11 acres at Waconda Lake. Compared to the No Action Alternative, this alternative would increase loafing and refuge habitat on the reservoirs for migratory waterbirds. The cycle of reservoir fluctuation and death of reservoir riparian vegetation would be the same as under the No Action Alternative and would have similar impacts on tree and shrub-nesting bird species. Grassland-nesting birds would not be affected by this alternative.

FWR Alternative.--This alternative would increase the average reservoir surface area during fall by 464 acres at Kirwin Reservoir and 790 acres at Webster Reservoir. The surface area of Waconda Lake would be reduced by 55 acres. Compared to the No Action Alternative, this alternative would almost double loafing and refuge habitat available at Webster Reservoir for migratory waterbirds and increase surface area at Kirwin Reservoir by almost 30 percent. At Waconda Lake, average fall reservoir surface area is similar to that experienced through the period of record and would not result in adverse effects for migratory waterbirds. The cycle of reservoir fluctuation and death of reservoir riparian vegetation would be the same as under the No Action Alternative; however, higher reservoir elevations would increase conservation pool filling rates, limit the development of woody vegetation below that which has established at the top of the conservation pool, and increase the frequency for the reservoir entering the flood pool. Fluctuation cycles under this alternative would have similar impacts on tree- and shrub-nesting bird species. Grassland-nesting birds would not be affected by this alternative.

Negotiated Alternative.--This alternative would increase the average reservoir surface area during fall by 152 acres at Kirwin Reservoir and 249 acres at Webster Reservoir. The surface area of Waconda Lake would be reduced by 11 acres. Compared to the No Action Alternative, this alternative would increase loafing and refuge habitat available for migratory waterbirds at Kirwin and Webster Reservoirs by 9 percent and 19 percent, respectively. At Waconda Lake, average fall reservoir surface area is similar to that experienced through the period of record and would not result in adverse effects for migratory waterbirds. The cycle of reservoir fluctuation and death of reservoir riparian vegetation would be similar to the No Action Alternative; however, slightly higher reservoir elevations would increase conservation pool filling rates, limit the development of woody vegetation below that established at the top of the conservation pool, and increase the frequency for the reservoir entering the flood pool. Fluctuation cycles under this alternative would have similar impacts on tree- and shrub-nesting bird species. Grassland-nesting birds would not be affected by this alternative.

Mitigation/Other Environmental Measures

The action alternatives improve habitat conditions for migratory waterbirds when compared to the No Action Alternative and produce impacts similar to the No Action Alternative for tree-, shrub-, and grassland-nesting migratory birds. Therefore, no mitigation measures are proposed for migratory birds other than that described for the interior least tern and piping plover in the "Endangered Species" section.

Net Impacts

The action alternatives improve habitat conditions for migratory waterbirds and produce impacts similar to the No Action Alternative for other migratory birds. There would be no net adverse impacts for tree-, shrub-, or grassland-nesting birds and a net beneficial impact for migratory waterbirds.

Endangered Species

Section 7(a)(2) of the Endangered Species Act (ESA) requires each Federal agency to consult with the Service to ensure that any action they authorize, fund, or carry out is not likely to jeopardize the continued existence of a listed species or result in the destruction or adverse modification of designated critical habitat.

Overview

Affected Environment - Brief Summary

The analysis of endangered species includes threatened, endangered, and proposed⁽⁴⁾ species that may occur within or migrate through the Basin.

Summary of Impacts

Under all the alternatives, given certain reservoir elevations and climatic conditions, incidental take could occur in low numbers for the interior least tern.

Impacts Criteria

The criteria centered on whether impacts occurred to species under the ESA or their critical habitat.

Affected Environment

At Reclamation's request, the Service provided a list of threatened, endangered, and proposed species that may be present within, or migrate through, the Basin. This list forms the basis for Reclamation's biological assessment prepared to comply with section 7(a)(2) of the ESA. The biological assessment contains current information on the status and distribution of these species and whether the proposed action may adversely affect them or designated critical habitat. The complete biological assessment can be found in attachment G.

Potentially Affected Species.--The Service identified the following species as potentially being affected by the proposed conversion of long-term water service contracts.

No proposed species, species of concern, nor critical habitat were identified by the Service in the Basin.

The State of Kansas also administers a program for the conservation of State-recognized threatened or endangered species. The following threatened and endangered species are known to occur or are likely to occur in the project area:

• Eastern spotted skunk (Spilogale putorius interrupta), threatened
• Eskimo curlew (Numenius borealis), endangered
• Peregrine falcon (Falco peregrinus), endangered
• Snowy plover (Charadrius alexandrinus), threatened
• White-faced ibis (Plagadis chihi), threatened

The State and federally listed bald eagle is the only listed species with State-designated critical habitats within the project area. All lands and waters within 5 air miles of public lands near Glen Elder, Kirwin, and Webster Reservoirs are State-designated as critical habitats for the bald eagle. Also, designated critical bald eagle habitats occur along a corridor that extends 100 yards landward from the water's edge on both banks of the main stem of the Solomon River.

Methodology/Analysis

Reclamation requested a list of potentially affected species and background and distribution information from the Service. The Service and the State of Kansas were contacted for further information regarding these species and their life history requirements. This information was used to develop a biological assessment by Reclamation in compliance with the ESA.

Impacts Analysis

Interior least terns have been documented nesting on the upstream face of Kirwin Dam below the bottom of the riprap. Nesting has been documented during extended periods when the reservoir fails to reach the bottom of the riprap, exposing suitable nesting substrate (Service, 2001). Piping plovers may nest on suitable substrate at other locations when reservoir surface elevations permit.

The interior least tern and piping plover were identified as possibly being affected by proposed operations at Kirwin and Solomon Reservoirs and Waconda Lake. If terns have established nests on the face of the dam and for any number of reasons, the reservoir surface rises enough to cover the nests or harass adults or chicks, and incidental take of a federally listed species may occur. This situation is possible under all of the alternatives, including the No Action Alternative.

Reclamation and the Service have entered into formal consultation for potential effects on the interior least tern. Discussions are ongoing concerning the level of incidental take and reasonable and prudent measures and terms and conditions necessary to minimize the level of incidental take. The scope of the terms and conditions includes prohibiting vehicular access to the upstream face of Kirwin Dam, erecting signs and installing buoys, nest relocation, transfer of eggs to incubation facilities, and monitoring.

It is also possible that piping plovers may find suitable nesting habitat when sand flats are exposed at the reservoirs. With low reservoir elevations and unpredictable climatic conditions, all of the alternatives, including the No Action Alternative, may result in relatively rapid rises in reservoir surface elevations that could swamp nests and eggs, drown chicks, and/or harass adults and chicks. If plovers have established nests within the reservoir basin and, for any number of reasons, the reservoir surface rises enough to cover the nests or harass adults or chicks, incidental take of a federally listed species may occur.

None of the alternatives considered, including the No Action Alternative, would adversely affect any State-listed species or critical habitat in Kansas.

Mitigation/Other Environmental Measures

To reduce the potential for vehicles to drive in the area where least terns may be nesting, barrier gates will be installed. This will eliminate unauthorized vehicle access in the area where nesting terns are present. Access into the area will be by foot traffic only. Once nesting and fledgling activities are completed, the gates will be opened to allow vehicles into the area for fishing.

Discussions are ongoing concerning the level of incidental take and reasonable and prudent measures and terms and conditions necessary to minimize the level of incidental take. The scope of the terms and conditions includes prohibiting vehicular access to the upstream face of Kirwin Dam, erecting signs and installing buoys, nest relocation, transfer of eggs to incubation facilities, and monitoring. The terms and conditions are identified in the "Environmental Commitments" section.

Net Impacts

Even with mitigation proposed for the least tern, under certain reservoir and climatic conditions, incidental take may occur for both the tern and piping plover. The Service has predicted that nine eggs and/or prefledged chicks may be taken incidentally each year. With implementation of the terms and conditions, this level of incidental take will not have significant adverse effects on the interior least tern.

Reservoir Wetlands and Riparian Vegetation

This section describes impacts in accordance with Executive Order 11990, which requires each Federal agency take action to minimize the destruction, loss, or degradation of wetlands⁽⁵⁾ and to preserve and enhance their natural and beneficial values; the agencies' responsibilities for conducting Federal activities and programs affecting land use, including, but not limited to, water and related land resources planning, regulating, and licensing. It evaluates the potential effects of the alternatives on wetlands and riparian vegetation associated with the periphery of the reservoirs.

Overview

Affected Environment - Brief Summary

The analysis includes wetlands and riparian vegetation at Kirwin and Webster Reservoirs and Waconda Lake.

Summary of Impacts

No net impacts are anticipated to reservoir wetlands or riparian vegetation.

Impacts Criteria

The analysis was based on reservoir operations and the ecological responses of pioneer and riparian vegetation communities.

Wetlands and riparian vegetation associated with Kirwin and Webster Reservoirs and Waconda Lake are important resources in the Basin because they provide food and habitat for terrestrial wildlife and migratory birds, reduce water temperature for reservoir fish, stabilize reservoir shorelines, enhance recreational opportunities, and improve aesthetic values.

Affected Environment

Kirwin and Webster Reservoirs began to fill in the early 1950s and Waconda Lake in the late 1960s. Since these reservoirs have reached the tops of their conservation pools, vegetation typically adapted to wet and moist conditions has established around their peripheries. In 1993 and again in 1995, as the reservoirs filled into their flood pools to record high elevations, inundation killed all of the wetlands and much of the riparian vegetation around the perimeters. Reservoir surface elevations have remained relatively high since 1993, and natural regeneration of wetlands and riparian vegetation is underway. Cottonwood, willow, cattails, sedges, and grasses are dominant species in areas where regeneration is occurring.

Much of the wetlands and riparian vegetation in the Basin is associated with these federally developed irrigation and flood-control reservoirs. These wet- and moist-soil plant communities are a direct result of reservoir development and can be positively or negatively affected by short- and long-term changes in climate and reservoir operations. Because reservoir wetlands and riparian vegetation are largely dependent upon moisture associated with the surface of the reservoir, this resource is most susceptible to changes in reservoir operations. Long periods of low reservoir surface elevations can result in desiccation and death, and inundation for prolonged periods can have similar consequences.

Areas of reservoir wetland and riparian vegetation remaining at Kirwin and Webster Reservoirs and Waconda Lake consist of herbaceous and woody plant communities containing grasses, sedges, cattails, cocklebur, smartweed, sunflower, hemp, willows, Russian olive, American elm, and cottonwoods. These plant communities range from mature tree and shrub associations in the driest and highest locations to shrub and herbaceous species in moister locations and to pioneer and invasive herbaceous species in the wettest locations subject to frequent inundation by fluctuation of the reservoirs. Numerous standing dead trees and snags resulting from the flooding in 1993 and 1995 are common at all three reservoirs.

Extensive mud and sand flats are exposed as reservoir levels recede. With favorable climatic and moisture conditions, these flats support large areas of herbaceous wetlands containing cocklebur, smartweed, cattails, sedges, grasses, and weeds.

Approximately 350 acres of riparian habitat remain at Kirwin Reservoir along the periphery of the reservoir and along the North Fork Solomon River, Bow Creek, and other tributaries to the reservoir (Service, 1996). Because much of Kirwin National Wildlife Refuge lies within the flood pool of Kirwin Reservoir, all of the wetlands and much of the riparian vegetation were lost during the 1993 and 1995 flood events. Webster Reservoir was subjected to the same flood events, and approximately 1,500 acres of riparian vegetation are thought to have survived (Zajic, 2001). Less than 400 acres of riparian vegetation remain at Waconda Lake (KDWP, 1996). These reservoir wetland and riparian communities, and those that may develop in the future, could be affected by other flood conditions and reservoir operations.

Shoreline stabilization, aquatic and terrestrial wildlife habitat, water quality, recreation, and aesthetic values result from the development of wetlands and riparian vegetation at these reservoirs. Like riverine riparian habitats, riparian vegetation at the reservoirs supports greater diversity of plant and animal species than the adjacent uplands.

Methodology/Analysis

The composition and respective acreages of reservoir riparian vegetation were obtained from existing reservoir (KDWP, 1996) and refuge management plans (Service, 1996). Hydrologic data were derived from hydrology model output. The analysis of impacts was based on an understanding of reservoir operations and the ecological responses of pioneer and riparian vegetation communities.

Impacts Analysis

No Action Alternative.--As a result of declining inflows, on-farm soil and moisture conservation practices, and other water use and conservation activities, the No Action Alternative would result in lower average reservoir surface elevations for Kirwin and Webster Reservoirs when compared to the period of record (1949-98). The average reservoir pool elevations at Kirwin and Webster Reservoirs during spring (averaged between May and June) is approximately 11 feet lower. The average reservoir pool elevation at Waconda Lake is approximately 2 feet higher when compared to the period of record (1967-98).

Lower average reservoir pool elevations, and associated smaller reservoir surface areas, would minimize the hydrologic connection between the remaining reservoir wetlands and riparian vegetation and their primary source of moisture for extended periods. This might shift herbaceous plant communities to those better adapted to drier conditions. Mature Russian olive, American elm, cottonwood, and willow trees might survive periods of extended hydrologic isolation if they are able to intercept groundwater or produce more extensive root systems to reach lower surface elevations. Immature trees might not survive extended dry periods.

During annual drawdown and/or prolonged reduced inflows, herbaceous wetland and riparian plants and shrubs might establish in the zone between the reservoir surface and the existing riparian vegetation. Although average reservoir surface elevations would generally be lower during spring, the reservoirs would continue to be operated as they have been in the past with the goal of filling the conservation pool as often as possible. Until 1993, Kirwin and Webster Reservoirs had last filled to the tops of teir conservation pools in 1970 and 1962, respectively. In contrast, Waconda Lake fills to the top of its conservation pool almost every other year. With climate as a major influence, these reservoirs will continue to display irregular patterns of partial filling between periods when they fill their conservation pools and possibly enter the flood pool.

Based on historic filling and flooding patterns, reservoir wetland and riparian vegetation would periodically be killed and re-establish. Depending on the interval between flood events, the composition of the vegetation would be different--short intervals between flooding would maintain herbaceous and shrub associations, while longer intervals would permit woody vegetation and trees to establish. However, irregular and unpredictable filling patterns and periodic inundation would prohibit long-term establishment of wetland and riparian vegetation below the vegetation that survived the 1993 and 1995 floods. The highly fluctuating nature of the reservoirs would also prohibit survival of riparian tree species below the top of the conservation pool.

Over the term of the contracts, the existing reservoir wetland and riparian communities would migrate onto substrate within the conservation pool and, barring long-term inundation, would result in greater acreage of wetlands and riparian vegetation adjacent to the reservoirs. However, under the No Action Alternative, it is inevitable that these reservoirs would return to flood pool elevations and most, if not all, of the reservoir wetlands and riparian vegetation would be inundated and killed.

The variability in climate, inflows, and annual areal extent of vegetation prohibits development of an accurate prediction of the amount and relative value of the vegetation that would develop below the existing riparian vegetation. Attempting to do so would produce results accurate only for the given year (in addition to being difficult to ascertain and expensive). Under the No Action Alternative, over the term of the contracts, the reservoir wetlands and riparian vegetation would experience cycles of inundation and death and lower surface elevations and expansion.

Irrigation Alternative.--This alternative would produce average spring reservoir surface elevations 1 foot higher than those under the No Action Alternative at Kirwin Reservoir and 3 feet higher at Webster Reservoir. The average spring reservoir surface elevation at Waconda Lake would not change when compared to the No Action Alternative. Because these reservoirs would fill to the top of the conservation pool as often as possible and would infrequently enter the flood pool, the effects of this alternative on reservoir wetlands and riparian vegetation would be similar to those of the No Action Alternative.

FWR Alternative.--This alternative would produce average spring reservoir surface elevations 5 feet higher than those under the No Action Alternative at Kirwin Reservoir and 9 feet higher at Webster Reservoir. The average spring reservoir surface elevation at Waconda Lake would not change when compared to the No Action Alternative. Because these reservoirs would fill to the top of the conservation pool as often as possible and would infrequently enter the flood pool, the effects of this alternative on reservoir wetlands and riparian vegetation would be similar to those of the No Action Alternative.

Negotiated Alternative.--This alternative would produce average spring reservoir surface elevations 1 foot higher than the No Action Alternative at Kirwin Reservoir and 3 feet higher at Webster Reservoir. The average spring reservoir surface elevation at Waconda Lake would not change when compared to the No Action Alternative. Because these reservoirs would fill to the top of the conservation pool as often as possible and would infrequently enter the flood pool, the effects of this alternative on reservoir wetlands and riparian vegetation would be similar to those of the No Action Alternative.

Mitigation/Other Environmental Measures

Because of the inherent, highly fluctuating nature of these reservoirs, the action alternatives produce impacts similar to those of the No Action Alternative; therefore, there are no mitigation measures proposed for reservoir wetlands or riparian vegetation.

Net Impacts

The action alternatives produce impacts similar to those of the No Action Alternative. Accordingly, there are no net impacts to reservoir wetlands or riparian vegetation.

Cultural Resources

Introduction

Cultural resources at the Project are administered under the National Historic Preservation Act of 1966 (NHPA) (as amended) and the Archeological Resources Protection Act (ARPA) (as amended). Each act has implementing regulations that specify consultation and protection procedures.

Overview

Affected Environment - Brief Summary

The analysis of historic properties includes any district, site, building, structure, or object that is included in or eligible for inclusion in the National Register of Historic Places (National Register).

Summary of Impacts

No net impacts are anticipated on cultural resources.

Impacts Criteria

The analysis was based on current and alternative reservoir operations and the presence of known cultural resources.

Affected Environment

Under Section 106 of NHPA, Reclamation must consult with the State Historic Preservation Officer, the Advisory Council on Historic Preservation Officer, and the Advisory Council on Historic Preservation when a proposal could affect historic properties listed, or eligible for listing, in the National Register. Section 110 of NHPA requires Federal agencies to manage and maintain historic properties on Federal land in a way that considers their historic, archeological, architectural, and cultural value, and to consider the effects of proposed actions during Project planning.

Methodology

Section 110 (a)(2) of NHPA and the Department of the Interior's "Guidelines for Federal Agency Responsibilities under Section 110 of the National Historic Preservation Act" require a Class III cultural resource survey of all Federal lands.⁽⁶⁾ Twelve previous surveys have been completed on portions of this Project, primarily on small tracts examined in advance of construction activities.

Analysis of Impacts

A records search for all Project lands was performed by Reclamation and the University of Kansas through the Kansas State Historical Society. Files at Reclamation's Nebraska-Kansas Area Office were also carefully examined. Records searches, as well as the two current comprehensive Class III cultural resource surveys have identified approximately 40 archeo-logical sites that had been recorded within this Project. Several other archeological sites have been recorded in adjacent sections.

Two current comprehensive Class III surveys will each produce a report for the archeo-logical surveys as well as site evaluations on all Federal lands within the potential area of impact, one for Kirwin Reservoir and one for Webster Reservoir.

Other surveys in the general area include surveys at Norton, Waconda, and Lovewell Reservoirs. Together, these earlier surveys indicated that prehistoric archeological sites do occur in this part of the State, particularly in the uplands and valley slopes.

Net Impacts

The action alternatives produce impacts similar to those of the No Action Alternative. Accordingly, there are no net impacts to cultural resources.

Native American Resources

Introduction

Reclamation is responsible for the protection and final disposition of such remains and certain cultural objects located on Federal land under the Native American Graves Protection and Repatriation Act (NAGPRA) of 1990. Cultural objects under this act include funerary objects, sacred objects, and objects of cultural patrimony. Any intentional removal of protected remains or sacred objects requires consultation with American Indian (Indian) Tribes and Native Americans that might be culturally affiliated with these objects. Removal can take place only after consultation is completed and an ARPA permit is issued by the Federal agency administering the land. Inadvertent discoveries require protection of the remains and consultation with the relevant Indian Tribes. Materials protected by NAGPRA are conveyed to the closest affiliated person or Tribe for final disposition.

Analysis of Impacts/Net Impacts

The action alternatives produce impacts similar to those of the No Action Alternative. Accordingly, there are no net impacts to Native American resources.

Indian Trust Assets

Introduction

Indian Trust Assets are legal interests in property held in trust by the United States for (Indian) Tribes, Nations, or individuals. The Secretary of the Interior (Secretary) is the trustee for the United States on behalf of Indian Tribes. All Department of the Interior (Interior) agencies share the Secretary's duty to act responsibly to protect and maintain ITAs reserved by or granted to Indian Tribes, Nations, or individuals by treaties, statutes, and Executive orders. These rights are sometimes further interpreted through court decisions and regulations. Examples of ITAs are lands, minerals, hunting and fishing rights, and water rights. Interior carries out its activities in a manner that protects ITAs and avoids adverse impacts when possible. When adverse impacts cannot be avoided, appropriate mitigation or compensation is to be provided in consultation with the affected Tribes and/or individuals.

Consultation initiated in 1995 identified no ITAs in the Project area.

Analysis of Impacts/Net Impacts

The action alternatives produce impacts similar to those of the No Action Alternative. Accordingly, there are no net impacts to ITAs.

Environmental Justice

Executive Order 12868 requires Federal agencies to identify and address "disproportionately high and adverse human health and environmental effects of its programs, policies, and activities on minority populations and low-income populations." Federal agencies must consider whether impacts of their activities place an undue burden on low-income or minority populations with respect to the environment or human health. The main tenet of this Executive order declares that no person or group should shoulder a disproportionate share of negative environmental or human health impacts associated with the implementa-tion of a Federal program, policy, or activity.

The Council on Environmental Quality regulations require that environmental justice be evaluated using three criteria:

• Whether impacts are significant or above generally accepted norms
• Whether the proposed program, policy, or activity poses a significant environmental hazard to a minority or low-income population which appreciably exceeds the risk to the population in general
• Whether impacts, when combined with effects of other projects, pose a cumulative environmental hazard to a minority or low-income population

No minority or low-income populations have been identified in the Basin that would be disproportionately affected by any of the alternatives, including the No Action Alternative. No disproportionate effects have been identified that would require mitigation measures in minority or low-income populations.

Biodiversity/Sustainability

The water-dependent flora and fauna of the Basin have been significantly altered since European settlement, as noted earlier in this chapter. Biodiversity was diminished during this period, especially with the construction of dams, groundwater pumping, and soil moisture retention practices by agriculture. The existing conditions, though sustained by human intervention, would not be significantly changed by the renewal of irrigation contracts. This is due to the similarity of reservoir acreage and streamflows now and under future scenarios.

Short- and Long-Term Effects and Unavoidable Adverse Effects

Introduction

The survival and distribution of water-dependent natural resources in the project area will be determined by the water supply. This supply is primarily a function of precipitation; however, Basin-wide water conservation practices and groundwater pumping have a significant impact. Of these factors, only water conservation within the district is relevant to the contract renewals.

Agriculture, dams, irrigation, and groundwater extraction have caused the most significant, long-term, and currently unavoidable effects to the area. These conditions would not significantly change with the renewal of contracts. Likewise, such short-term effects as dam operations and irrigation scheduling resulting from contract renewal are not significant because they fall within the natural variability of precipitation for the region.

Reservoir Wetlands and Riparian Vegetation

It is difficult to predict short- and long-term effects on reservoir wetland and riparian vegetation because their establishment and demise are predicated on weather, runoff, and streamflows. Within the short term, it is believed that existing conditions will persist and that reservoir wetlands and riparian vegetation may increase. However, over the long term, all of the alternatives, including the No Action Alternative, would perpetuate reservoir surface fluctuation that would permit reservoir wetlands and riparian vegetation to establish when the reservoir surfaces are relatively low and then inundate and kill the newly established vegetation when reservoir surfaces rebound and/or enter the flood pool. Relatively long periods of low reservoir surface would permit the establishment of trees within the conservation and flood pools. Most, if not all, of these trees and other vegetation would be lost when the reservoirs filled their conservation pools or entered the flood pool. Such a loss would be unavoidable.

Migratory Birds

The establishment of mature trees in and above the conservation pool would provide habitat for breeding and nesting migratory birds. Such habitat would be a short-term benefit because these trees would likely be killed when inundated by high reservoir surface elevations.

Endangered Species

Over the long term, it is possible that least tern and piping plover nests, eggs, and/or young would be inundated and lost. Reclamation is consulting with the Service to identify measures to minimize impacts on interior least terns. Some unavoidable losses of least terns are likely to occur as a result of fluctuating reservoir levels. The Service has indicated that such losses would not jeopardize the continued existence of the species and will provide Reclamation with an incidental take statement for these losses.

Cumulative Effects

No cumulative effects have been identified.

Environmental Commitments

An environmental commitment plan developed to minimize adverse effects of the proposed action is located in attachment H.

1. Once an acceptable historic version of the model was developed, it was modified slightly for use in evaluating the alternatives. Irrigable acres for each unit were set to their full development levels. Based on practices in recent years, canal deliveries for the Kirwin and Webster Units were restricted to the months of June, July, and August. An algorithm was developed to simulate the conservation practice of delivering at the farm only 12 inches of water per acre per year from Kirwin and Webster Reservoirs. The algorithm prioritizes the monthly deliveries in the order of July, August, and June. For simulations involving assumptions of increased conveyance and on-farm efficiencies, reach gains below irrigation districts were modified to reflect a corresponding decrease in return flows.

2. Reclamation expenditure estimates at Reclamation reservoirs are based on data from the 1996 National Survey of Fishing, Hunting, and Wildlife-Associated Recreation by the Service and Bureau of the Census. Information from a 2000 Corps of Engineers' study and from a 1999 American Automobile Association booklet was used to divide expenditures into categories from which regional impacts can be estimated.

3. The IMPLAN model, developed by the Forest Service, uses the Department of Commerce national input-output model to estimate flows of commodities used by industries and commodities produced by industries. Social accounts are included in the IMPLAN database for each region under consideration. Social accounts represent the flow of commodities to industry from producers and consumers as well as consumption of the factors of production from outside the region. Social accounts are converted into input/output accounts and the multipliers for each industry within the region, which accounts for the multiple effects of changes in spending described in the section above. The percentage of expenditures in each category that would remain within the region and expenditures that would flow outside the region are also accounted for within IMPLAN.

4. Threatened species are those species likely to become endangered within the foreseeable future throughout all or a significant portion of its range. Endangered species are those in danger of extinction and eligible for conservation under the ESA.

5. The most widely accepted definition for wetlands is published in the Clean Water Act (Public Law 92-500) as those areas that are inundated or saturated by surface or groundwater at a frequency and duration sufficient to support, and that under normal circumstances do support, a prevalence of vegetation typically adapted for life in saturated soil conditions. For purposes of analysis in this document, reservoir wetlands and riparian vegetation were not differentiated.

6. A Class III survey means that all lands were visited, and the ground surface was carefully inspected to locate any unrecorded historical sites. There are two comprehensive Class III cultural resource surveys currently underway on this Project, both of which are being conducted by the University of Kansas.