Reclamation's Major Urban Conservation Opportunity--Efficient Turf Irrigation
Urban Conservation Opportunity Efficient Turf irrigation
Studies indicate that in the Western United States., 50 to70 percent of the water used in cities and towns is applied to irrigate landscapes. These studies also show that landscape irrigation uses up to twice the amount of water as plants require. Potentially one-fourth to one-third of the water delivered from U.S. Bureau of Reclamation projects to cities and towns is wasted.
Eight plots were established with different turf grass mixes in 2008 (Table 1) at Northern Water in Berthoud, CO. The official soil series at the Conservation Gardens is a Nunn clay loam, 0 to 1 percent slope, although soil tests indicated a silty clay soil texture. Water meters, rain gauges and tipping buckets were used to accurately measure water applied and soil moisture sensors were used to maintain water supply to plants as needed.
Several grass mixes offer lower water use for turf installations. Grass mixes instead of single varieties offered best characteristics of each grass and may have an advantage in responding to different climate and irrigation conditions. Foothills Mix used 22 percent less water than Low Grow Mix. Reveille Texas hybrid blue grass used 14 percent less water than Low Grow Mix. Soil water balance calculated ET and total applied water (flow meter data plus effective Berthoud precipitation) were in substantial agreement. The flow meter data were a valuable check for the soil water balance calculation, providing instrumentation redundancy and confirmation that the calculation technique was valid.
This study showed that Reveille Texas Hybrid Bluegrass and Foothills Mix had substantially lower seasonal ET than Canada Blue Fescue, Forever Green Mix, and Low Grow Mix. Monthly ET patterns also showed Reveille and Foothills Mix ET declining more rapidly in late summer than the other three turf varieties. These differences can be exploited for landscape water conservation.
The following documents were not reviewed. Statements made in these documents are those of the authors. The findings have not been verified.
Urban Conservation Opportunity Efficient Turf irrigation (final, PDF,
By Ms. Mary Hattendorf
Report completed on March 01, 2010