The City's ASR program diverts excess spring flow in the winter and spring and stores it in the aquifer system for use during the summer and fall.
The City and surrounding communities use groundwater and spring water as their sources of drinking water. To address year-to-year declines in groundwater levels and maximize the use of existing water rights, GSI helped the City develop an ASR program designed to divert excess spring flow in the winter and spring and store it in the underlying aquifer system for use during the summer and fall. The springs originate from shallower portions of the same basalt aquifer system that the City’s watershed wells are completed in. During the winter and spring when demand for water is predictably low and spring flow is seasonally high, these springs are capable of supplying more water than is needed or that can be stored by the City’s water system. GSI evaluated the feasibility of whether excess spring flow could be diverted and conveyed to one or more of the City’s existing wells to artificially recharge the basalt aquifer system, replenish groundwater levels, and improve summer pumping rates in the City’s watershed wells.
Following positive results from the feasibility study, GSI developed the limited license application and helped the City obtain regulatory approval, and designed a retrofit to convert an existing City well into an ASR recharge and recovery well. GSI has provided ongoing operational, monitoring, and permitting support since pilot testing began in 2012. The City’s ASR program has increased the reliability of its other municipal supply wells and has been essential to the City’s management of its water resources.
GSI’s work has involved: