Safe drinking water is an important and basic need for everyone. In recent years, Source Water Protection (SWP) has become a growing issue for public safety and health. In 1996, the U.S. Environmental Protection Agency (USEPA) established a new requirement under Section 1453 of the 1996 Safe Drinking Water Act for each state to develop a Source Water Assessment and Protection Program (SWAP) to assess all public drinking water sources. SWAP has two components: assessment and protection. The assessment component was mandatory and assessment reports were completed in the early 2000s. The second component, protection, is voluntary and consists of developing a SWP plan. These SWP plans will: (1) delineate the critical area for the surface water source; (2) provide an inventory of existing and potential sources of regulated and some unregulated contaminants in the assessment area; (3) determine the susceptibility of the public water source to contamination; (4) identify management options for best protecting a system’s water source(s); (5) review contingency plans in the event of contamination events; and (6) investigate the potential for new sources.
Capital Region Water (CRW) operates two intakes in the Lower Susquehanna River Basin. The primary source is the DeHart Reservoir in Rush Township, Dauphin County, PA. The secondary source is the mainstem of the Susquehanna River near the City of Harrisburg, PA. The system serves a population of approximately 67,000 people.
The watershed for the DeHart Reservoir is approximately 20 square miles. The watershed for the Susquehanna River intake is 23,563 square miles, while the study area is only 596 square miles. The major tributaries to the Susquehanna River that enter within the study area, from north to south, are Penns Creek, Mahanoy Creek, Mahantango Creek, Wiconisco Creek, the Juniata River, Sherman Creek, and Clark Creek.
The local community, watershed protection partners, and local officials play a large role in protecting drinking water. They have firsthand knowledge of the watershed and issues that threaten the safety of the water. They also play a key role in educating their neighbors about SWP issues. Steering committee meetings were held to include input from community members and local officials.
The watershed upstream of each public surface water supply intake was delineated into three protection zones (Zones A, B, and C) based on the time-of-travel (TOT) approach approved by DEP, and mean annual stream velocities built into the National Hydrography Dataset Plus (NHDPlus). Zone A represents a 0.25-mile buffer on either side of the stream within a 5-hour TOT. Zone B represents a 2-mile buffer on either side of the stream within a 25-hour TOT and Zone C makes up the remainder of the watershed. The 5-hour and 25-hour TOT delineations represent the entire drainage area within their given upstream times of travel.
An inventory of potential sources of contamination (PSOCs) was completed for the entire assessment area. PSOCs include activities and locations that use, store, transport, or dispose of contaminants. PSOCs can be point or nonpoint pollutants. The sources were identified by using Geographic Information Systems (GIS) data layers. The GIS layers used for the point source analysis include, but are not limited to, regulated facilities, underground storage tank locations, hazardous material locations, and regulated discharges. Maps and tables of the point source PSOCs were also created. Nonpoint pollutants were evaluated using 2005 land use data from the U.S. Geological Survey (USGS). The potential for a public drinking water supply to draw contaminated water is determined by the susceptibility analysis. The susceptibility analysis utilizes a series of matrices that assign a susceptibility rating of “A” thru “F” to the PSOCs. An “A” rating is the highest susceptible and highest protection priority and a rating of “F” is the least susceptible and less of a protection priority.
CRW will use a variety of management options to develop a comprehensive approach to SWP and monitoring of its water supply from the identified PSOCs. Much of the effort will rely on public education and enhancing their relationship with local stakeholders, including state agencies and first responders.
Management options include educating CRW customers and government officials about the importance of SWP, continually monitoring PSOCs in the watershed, and becoming active in the Susquehanna River Basin Commission’s (SRBC’s) Early Warning System (EWS).
CRW maintains an emergency response plan that is regularly updated. The plan includes emergency contacts and provisions for alternate water sources. CRW can rely solely on one source, if the other source is contaminated.
CRW will work closely with local and county first responders in the event of a contamination or accident event that may threaten the water supply. If the event causes the Susquehanna River to become unusable for an indefinite amount of time, a new source of water will need to be identified and developed.