Bacteria, Geochemistry, and Hydrology: an Investigation of the Mechanisms of Clogging to Determine How Best to Address Them in Wells and Drains for Improved Operation and Maintenance
* What are the bacterial, geochemical, and hydrological mechanisms of clogging and how best to address them in wells and drains to improve operation and maintenance?
There are some related studies being conducted in Reclamation with regards to bacterial growth quorum-sensing inhibition, and prevention on reverse osmosis (RO) membranes. These activities involve chemical research on the molecular level to elucidate compounds that will prevent bacteria from forming biofilms. However, in dams and ground water systems, the factors involved in pipe and drain clogging are complex. The focus of this work is to determine the general bacterial, geochemical, and hydrological mechanisms involved in clogging on the macro scale. While assisting Principal Investigators with molecular inhibition research, technology transfer may be site-limited or unavailable for some time. The goal of this activity is to improve water delivery, water infrastructure reliability, and safety by determining the most efficient use of conventional methods.
Need and Benefit
In 2004, numerous clogging issues involving biofouling in toe drains and outlet works were addressed by the Ecological Research and Investigations Group. As drains age, there seems to be an increase in the occurrence of drain obstructions. Literature searches on the subject of clogging revealed only a few resources on specific methods to address these types of water-related clogs. Both Reclamation and the U.S. Army Corps of Engineers (Corps) have developed documents to address drainage issues; however, there is little guidance available on addressing specific biofouling problems. Further discussions with Reclamation personnel on the issues of biofouling and clogging in dam structures, drains, and ground water wells revealed that approximately one-third to one-half of the drains that are video surveyed contain evidence of biofouling. The Alamosa Field Office reported that ground water well issues currently take approximately 20 percent of their total labor time. Further, without effective operation and maintenance, ground water well productions may deteriorate to the point that drilling replacement wells is required.
General scoping activities reveal that most lateral drains (up to 80 percent) and numerous ground water wells experience decreased flow and productivity due to clogging. A review of photography produced from some in situ drain videos reveal a variety of materials reside in the drains contributing to clogging. Conglomerations of organic debris (biofilm, twigs, and leaves) to pebbles, sand, and/or crusty precipitate exhibiting a wide range of colors indicate numerous culprits on a macroscopic scale. A better understanding of mechanisms, both geochemical and biological, improves treatments, especially in environmentally sensitive and remote areas, ultimately reducing operation and maintenance costs. Improving treatment methods improve reliability and cut down on waste in specifying and implementing maintenance.
Contact the Principal Investigator for information about these documents.