Prettyboy Watershed

About the watershed
The Prettyboy watershed, an 80 square-mile watershed whose headwaters originate in York County, Pennsylvania, flows through Carroll County, Maryland and feeds the Prettyboy Reservoir located in Baltimore County, Maryland. The Prettyboy Reservoir is one of three reservoirs in the Baltimore Metropolitan System that collectively provides water to 1.8 million consumers in Baltimore City and surrounding areas. In addition, throughout the watershed there are both public and private wells that are hydrologically linked to the Prettyboy Reservoir, including two public water systems in Carroll County that supply groundwater to residents in Manchester and Hampstead.

Current land use reflects more than three centuries of social, economic and demographic change. At present, the watershed has about 15 percent developed land, 47 percent agricultural land (dominated by cropland at 37 percent) and 38 percent forests, wetlands, and water (dominated by forests at 34 percent). The largest contiguous block of forest borders the Prettyboy Reservoir and is on land owned by Baltimore City; the remainder is fragmented into patches by agricultural and low-density residential land use.

Land use is converting from farms and forests to home sites, as residential development spreads out from the Baltimore suburbs and along the Route 30, primarily in Manchester and Hempstead and further north in Pennsylvania. The loss of forests, farms and riparian vegetation, coupled with increased stormwater runoff, septic systems, the impacts of roads and increasing deer populations, has caused concerns about water quality and the future protection of this vital source of drinking water.

Threats to Source Water
Of Baltimore County’s three reservoirs, the Prettyboy Reservoir (PBR) is the most impaired and has the highest algae levels. Dissolved phosphorus is the primary contributor to excessive algae growth in the Prettyboy Reservoir. Sediment erosion from farms, roads and construction sites, fertilizers on crops, home lawns and gardens, and wastewater treatment plants are probable sources. As a result of improved wastewater treatment in recent years, phosphorus from wastewater treatment plants has declined.

High algae levels, caused by phosphorus, cause taste and odor problems and make drinking water more difficult and expensive to treat. In addition to high phosphorous levels, watershed managers are also very concerned about increasing chloride concentrations, although they are currently below EPA-recommended guidelines. Road salt and de-icing of parking lots are probably the main cause. Increasing residential development and the corresponding loss of forests will continue to exacerbate these problems in the future.

Overall, groundwater was found to be of high drinking water quality. The primary threats to ground water supplies in Carroll and York Counties are nitrates (fertilizers), synthetic organic compounds (pesticides and fertilizers), and volatile organic compounds (benzene and other gasoline derivatives, such as MTBE).

GIS Analysis
The GIS analysis was conducted using a new GIS Mapping Methodology. The results of the conservation priority index overlay highlight the importance of the forests along the Gunpowder River and other tributaries for the maintenance of water quality. Gaps in riparian forests along many small streams may allow nonpoint pollutants to enter the system.

The results of the restoration priority index overlay for agricultural lands and other green space show the potential influence of areas that are distant from the resevoir on water quality. This result is directly related to the steeper topography of the northern watershed.

The stormwater management priority index overlay indicated parcels, subdivisions, and towns where storm water management needs to meet very high performance standards in order to avoid contamination of source waters. Most of these areas include roads that follow or parallel streams.

Financing Opportunities

  • Create new local sources of land conservation funding that focus on protection of forests.
  • Broaden the allowed use of the Maryland WQSRF to allow funding for projects that prevent or mitigate nonpoint source pollution.
  • Create water utility surcharge to pay for conservation and restoration throughout the watershed.
  • Support restoration of full funding for Program Open Space and other programs.
  • Farmland Protection Program: With the significant increase in available funding available under the newly signed Farm Bill, Baltimore and Carroll Counties should apply for an FPP grant, possibly in conjunction with one of several local land trusts.

In October 2003, a public meeting to present many of the water resource protection issues that had been identified in the Stewardship Exchange Team Report to the community. These issues included forest sustainability, growth management, private land stewardship and public education. In general, participants agreed that in order to address many of these complex issues, there is a need for a citizen-led watershed coalition that would serve as an umbrella organization for the various private sector land trusts, preservation groups, citizen associations and watershed associations, coordinating and focusing efforts on the Prettyboy Watershed.

As a result of the high level of support from citizens at the public meeting, a core group of citizens formed the Prettyboy Watershed Alliance. Since the Fall of 2003, the Alliance has been meeting regularly and has begun planning activities to build capacity and citizen involvement throughout the watershed. Their first major activity is a Prettyboy Watershed Awareness Day planned for Spring 2004 as a way to build citizen awareness and involvement in watershed protection. A significant private donation from a local landowner is funding the groups initial activities.