Gauging our water supply
Does Adams County have enough water to meet current and future demands? The short answer is, we don’t know. It is unclear when we will reach the limit of water usage our surface and groundwater sources can support. In fact, there is some reason to believe demand already exceeds safe water yield in areas of Adams County. A number of organizations, including the Watershed Alliance of Adams County (WAAC), are collecting data so that we can better understand water availability and guide water management practices.
During this rain-soaked late summer and early fall, it seems as if our water supply must be more than sufficient for current needs and any future growth. Yet, Adams County has a limited water supply; virtually all of our streams and creeks originate in the county. We rely on precipitation to keep our streams and creeks running and to maintain our groundwater supply. During droughts, this can be problematic. Even when it rains, the soils and geology of this area allow only seven inches of water to infiltrate the ground. A lot of water simply runs out of the county.
The Marsh and Rock Creek watershed has been designated a Critical Water Planning Area by the Pennsylvania Department of Environmental Protection, which means that demand for water in this watershed exceeds or threatens to exceed available supply. We do not have a complete picture of how much water can be withdrawn from the Marsh and Rock Creek watershed before we threaten the health of the ecosystems supported by the watershed or existing human uses. In the past, when deciding whether to approve major water withdrawals, organizations that regulate water draws have been forced to rely on models and best guesses about water availability.
Beginning in 2010, WAAC began collecting water supply data for Marsh Creek through the use of a staff gage, which is essentially a tall ruler positioned in a stream to measure stream height. WAAC members took periodic measurements of Marsh Creek during the 2010 and 2011 drought seasons using the staff gage and used that data to calculate estimated flows.
Understanding how much water actually flows through Marsh Creek is an important first step in evaluating how much water can be withdrawn sustainably. Maintaining sustainable water usage through informed permitting decisions and conservation efforts will ensure that residents’ water needs continue to be met and our streams remain healthy.
WAAC needs you – members of the community, including children – to volunteer to periodically take and report stream flow measurements from additional staff gages that will be placed on streams throughout the county. At a time when funding for more-sophisticated stream gages (such as the one from the U.S. Geological Survey for continuous real-time stream monitoring of the Conewago Creek near East Berlin) has decreased nationwide, volunteer efforts such as WAAC’s Marsh Creek assessment project are an important part of understanding and allowing us to protect our water supply. WAAC is continuing its Marsh Creek assessment project and welcomes volunteers to assist with the data collection effort. For more information, please contact Adam MClain, the Adams County Conservation District Watershed Specialist, at .
Carrie Russell is an environmental attorney and a member of the Board of the Watershed Alliance of Adams County (WAAC). WAAC’s web address is www.adamswatersheds.org.