Brewster Integrated Water Resource Management Plan (Phases II and III)
In 2009, the Town of Brewster Comprehensive Water Planning Committee (CWPC) recognized that an integrated approach was needed to protect and restore the Town’s waters. Integrated water management recognizes that impacts to groundwater also affect surface waters and vice versa. Both water quality and quantity impacts are possible, so any evaluation of the Town’s water resources must consider both.
The graphic below shows how day-to-day activities can change the quality of drinking water and the quality of fresh water ponds and coastal estuaries. For example, chemicals flushed down a toilet into a septic system can impact water quality in downgradient ponds or coastal estuaries. Pollutants on town roadways (hydrocarbons, fertilizers, and pet wastes) are collected in stormwater runoff that flows into waterways or soaks into the aquifer. Over-pumping an aquifer for water can lead to lower water levels in ponds and to impacts to wetlands and their habitat. A truly Integrated Water Resources Management Plan (IWRMP) addresses these impacts on the Town’s groundwater, surface water, and coastal waters. Planning for the future now will help to mitigate and minimize these impacts to the Town’s water resources.
Introduction to Phase III
Phase III of the IWRMP will provide an assessment of the challenges and proposed solutions to manage the Town’s water resources. The integrated approach will address the components of water resources planning - including an evaluation of wastewater and nitrogen management alternatives, and the development and finalization of updated by-laws and regulations to implement the stormwater management recommendations developed during Phase II. The overall goal is to plan for sustainable water resources both now and in the future.
Brewster has some remarkable water resources. The Town is located directly over its water supply, a sole source aquifer, so any activities on the land surface can potentially affect the condition and sustainability of the water supply. The Town also has approximately 80 ponds that are valued for their aesthetic, recreational, and ecological resources. These ponds are fed by both groundwater and water surface, so they can be impacted by either. The Town also owns significant areas of beach and salt marsh along Cape Cod Bay, which can be impacted by stormwater pollutants.
Brewster’s population growth in Brewster increased rapidly from 827 people in 1940 to 9,820 people in 2010. The effects of this population growth and the associated development can impact the Town’s water resources in the following ways:
Increased groundwater withdrawals to meet the increasing population demand can directly lower water tables, pond levels, and streamflows;
Increased numbers of septic systems can impact the quality of all waters;
Increased amounts of nitrogen and phosphorus in groundwater, ponds and coastal waters can affect their quality; and
Increased impervious surfaces (rooftop, roads, and parking lots) can result in greater stormwater runoff and lower water quality.
IWRMP Phase III Goals
The Horsley Witten Group, Inc. (HW) was contracted to perform Phase III of the IWRMP for the Town of Brewster and began work in June 2013. This phase of the IWRMP will build on the work completed in Phases I and II, and other projects with the following goals:
Evaluate the Pleasant Bay nitrogen management alternatives identified in the Phase II report and select a preferred plan with recommendations for what Brewster needs to do to restore water quality within Pleasant Bay;
Finalize recommended stormwater regulations developed in Phase II;
Encourage proper management of stormwater, septic systems, fertilizers and other potential pollutants that impact Brewster’s Ponds (e.g., new regulations);
Continue with current outreach activities (e.g., website, brochure); and
Facilitate communication between the CWPC, the Cape Cod Commission, the public, and with other Town boards and agencies involved in the project.