Sustainable water management initiative grant - site screening, design, permitting & implementation of demonstration BMPs
The City of Concord selected Weston & Sampson to conduct a sustainable yield and drought management study that focused on the city’s two primary water sources, Penacook Lake and the Contoocook River, as well as possible source alternatives.
The goals of this study were two-fold: First, current water sources were evaluated to assess the city’s ability to meet water demands during drought conditions and satisfy maximum demand pumping requirements. Second, the study identified alternative sources of water, including potential groundwater sources, and presented a qualitative assessment of those sources.
Hydrologic analyses based on derived and historical streamflow and pumping records provided the city with an understanding of the current water supply and sustainable yield of the Penacook Lake system.
We also developed an interactive spreadsheet model of the Penacook-Contoocook system to provide a scientific backbone to the pumping scheme currently in place and to standardize the pumping procedure from operator to operator, since too little pumping could result in insufficient reservoir levels, but too much pumping would decrease water quality in the lake. We developed versions of the model predicting current and future demands and lake elevations for drought and normal hydrologic conditions, which are currently being validated with actual readings from Penacook Lake.
Weston & Sampson also identified six possible alternatives to alleviate the city’s water needs for the future, including several groundwater sources and an additional surface water source - the Merrimack River. These alternatives will be assessed in the City of Concord’s next study, focusing on development of a new source to provide water for the future.