As part of a continued effort to meet the water demands of a growing community, the Southington Water Department hired Weston & Sampson to assist with a hydrogeologic evaluation of their Dunham Place wellfield property and locating, designing, and constructing a 3 million-gallons-per-day (MGD) production well. They also asked us to design the pump house and associated appurtenances to connect the new well to the existing system and assist them through a substantial Connecticut Department of Energy and Environmental Protection (CTDEEP) Diversion Permitting effort for the entire wellfield.
Due to the significant aquifer depths of over 100 ft, a typical test well drilling effort was considered to be extremely expensive. Our hydrogeologic team instead used subsurface data from a variety of sources to construct a 3D geologic model of the aquifer to identify the most favorable and permittable locations within their property. The model considered depth, saturated thickness, aquifer thickness, and transmissivity such that only two test wells were needed, saving tens of thousands of dollars in drilling fees. We then used the model to identify a location for a 36-inch x 24-inch x 116-ft-deep gravel pack, high-capacity production well (Well 10).
In concert with the Well 10 project, we also conducted a thorough hydrogeologic review of 30 years of pumping, aquifer, wetland, and streamflow monitoring data to establish a safe yield for Well 9. We packaged the safe yield along with associated quantification of impacts to sensitive receptors into a 188-page hydrogeologic report to CTDEEP in support of the 3 MGD diversion permit for Well 9 in only three months.
Diversion Permit Application Materials for Well 9 are currently under review by CTDEEP. Well 10 is currently under construction and is scheduled to be able to produce up to 3 MGD. Design is also underway for the pump house and appurtenances to prepare for production before the next high-demand season. Once these wells are running at capacity, the town will not only have added much-needed redundancy to their water supply, but will have done so in a way that does not compromise the long-term capacity of the wellfield or sacrifice other nearby natural resources.
Project Features:
- 3D hydrogeologic modeling
- groundwater flow modeling
- test well drilling
- well design
- pump station design
- hydrogeologic safe yield analysis
- hydrogeologic impact analysis
- CTDEEP Diversion Permit