Home > Explore! > Ground Water and Wells > Water Resources Planning > March 2010 Notes
Water Resources Planning Committee
March 24, 2010
9:00 - 11:00 AM
U.S. Geological Survey
Maine Water Science Center
196 Whitten Road
- Current conditions: We briefly reviewed ground water conditions around the state by viewing several wells in the USGS's ground water monitoring network. Statewide, ground water levels in late March were normal to high.
- Citizen Trade Policy Commission. Marvinney provided a brief review of process with the Citizen Trade Policy Commission to consider the potential impacts of international trade agreements on Maine's ability to regulate ground water withdrawals. The final report is on the internet http://www.maine.gov/doc/nrimc/mgs/explore/water/planning/wrpc-final-report.pdf. Marvinney presented an overview of the report to the Natural Resources Committee on 2/18/2010, which was well received by the Committee.
- Review of work in Freeport watersheds
- Overview and flow measurements - Dan Locke (MGS). Dan provided an overview of the project, which we have worked on since 2008. Dan located five stream flow measurement sites on Harvey Brook and Merrill Brook and took weekly measurements throughout the summer and fall of 2009. Due to weather conditions, he was able to measure a very broad range of flows. He also augmented aquifer information with additional thickness and water table information. Two boreholes were drilled in February 2010 to better characterize the aquifer materials, stratigraphy, and water levels near the northern boundary of the study area. All this information was used in modeling. Dan's flow measurements were used to calculate monthly median flows, which were essential data for the modeling effort by Martha Nielsen.
- Ground water and modeling - Martha Nielsen (USGS). Martha provided an overview of her water budget and ground water modeling.
- Estimated detailed water use for the study area using information on the water district's distribution network and a coefficient of 60 gallons/person/day (from Maine water utility data), 2.4 people per household (census data). Per capita water use in Maine is decreasing, and future analyses may revise the usage downward.
- No major irrigators in the study area.
- Aqua Maine uses about 105 million gallons/year, which is about 85% of ground water use.
- The USGS equations for annual water discharge do not work on these watersheds because they are too small, less than 10 mi2.
- Seven percent of the ground water in the model comes from north of the model - the borehole data was critical to confirming this.
- Well pumping accounts for 7% of the aquifer water budget.
- Next steps include running scenarios with different pumping regimes to understand the sensitivity of the model, different recharge rates (e.g. drought conditions). Modeled impacts on stream flows may help us understand if there are any concerns with pumping relative to Chp. 587 rules.
- Final report expected December 2010.
- Potential basins for 2010-2011 investigations. With the conclusion of the Freeport project, Marvinney provided maps of several watersheds for consideration as new project areas. There was lively discussion of each, enumerating pros and cons for study in each area. At the conclusion of the discussion, WRPC members agreed that MGS should select one of the following watersheds based on follow-up discussions with the water districts: 1) Branch Brook, 2) North Yarmouth, 3) North Berwick, with Branch Brook being the preference.
- D. Bell, Agricultural Council of Maine
- A. Fisk, Maine Dept. Environmental Protection
- L. Hertz, Maine State Planning Office
- T. Hobbs, Maine Potato Board
- D. Locke, Maine Geological Survey
- R. Marvinney, Maine Geological Survey
- J. McNelly, Maine Water Utilities Association
- M. Nielsen, USGS
- G. Stewart, USGS
- S. Timpano, Maine Inland Fisheries and Wildlife
- A. Tolman, Maine Drinking Water Program
- T. Weddle, Maine Geological Survey
- A. Wong, Maine Rural Water Association
Last updated on August 20, 2009