water resources

Management Challenge

The White Clay Creek watershed usually receives abundant rainfall. Nevertheless, due to accelerated real-estate development in recent decades, demand has outpaced supply, creating a shortage of water, especially during periods of drought. A sustainable, consistently high-quality water supply is critically important.

Roles and Responsibilities

The Pennsylvania Department of Environmental Protection (PADEP), the Delaware Department of Natural Resources and Environmental Control (DNREC), the Delaware River Basin Commission (DRBC), the Environmental Protection Agency (EPA) and the Army Corps of Engineers (ACOE) are the primary governmental units responsible for the management of water resources within the White Clay Creek watershed.

Goals and Key Actions

The following sections set forth goals and suggest key actions the White Clay Creek Watershed Management Committee, in conjunction with the primary agencies responsible for water resource management, might take to achieve the goals.

Drinking Water Supply - Goals

  • Conserve and maintain the quantity and quality of White Clay Creek's stream flow.
  • Protect the Cockeysville Marble formation.
  • Ensure a sustainable water supply that can accommodate future demand.
  • Provide reliable water flows in New Castle County; resolve questions relative to the Thompson Station reservoir project.
  • Ensure minimum instream flow standards along White Clay Creek.

Drinking Water Supply - Key Actions

  • Monitor the Hockessin, Delaware, wells of the Artesian Water Company to ensure that production does not contaminate or reduce the recharge rates of the Cockeysville Marble formation aquifer.
  • Encourage groundwater recharge to increase base flow in the streams for existing water supply purposes.
  • Establish limits for withdrawals from all Cockeysville Marble formation aquifer recharge areas.
  • Determine the need for a future surface-water allocation for White Clay Creek for Pennsylvania communities.

Aquatic Life - Goals

  • Protect a fully functional and diverse ecosystem supported by White Clay Creek.

Aquatic Life - Key Actions

  • Base state and federal regulations implementing the Federal Clean Water Act (1987) upon water-quality criteria that ensure the survival and propagation of both sport fish and aquatic invertebrates.

Education and Research - Goals

  • Achieve a better understanding of the impact on biodiversity of various watershed uses.
  • Protect the qualities that make the White Clay Creek watershed a "living laboratory for education and research.
  • Ensure access to watershed streams for education and research.

Education and Research - Key Actions

  • Conduct new research on the effects of new and traditional uses on watershed biodiversity.
  • Protect valuable research areas from the introduction of exotic species, particularly the 1,800-acre Experimental Watershed managed by the Stroud Water Research Center located on the East Fork of the East Branch of White Clay Creek.
  • Promote the continuation of, and seek increased funding for, educational programs and volunteer monitoring.

Water Quality - Goals

  • Achieve consistency between the water-quality goals set by Delaware and Pennsylvania.

Water Quality - Key ActionsBase water-quality goals for each state on a technical evaluation of the watershed as a whole. Existing Water Quality - Goals

  • Correct inadequacies in existing data about dissolved oxygen, toxins and temperature.
  • Reduce risk of gastroenteritis to people who swim in untreated water from the Delaware portion of White Clay Creek.
  • Reduce levels of nutrients (nitrate and phosphorus) in the creek.
  • Reduce turbidity in the creek.
  • Assess and control the impact on aquatic life of zinc, PCBs and DDT.
  • Address cumulative impacts of excessive runoff and earth disturbance.

Existing Water Quality - Key Actions

  • Conduct field studies of photosynthesis/respiration to determine whether dissolved oxygen levels are sufficient to support fish, aquatic life and wildlife.
  • Develop strategies to reduce the levels of Enterococcus bacteria in the Delaware section of White Clay Creek (potential sources include agricultural nonpoint sources, urban runoff, wildlife, malfunctioning septic systems and publicly owned treatment systems).
  • Develop strategies, in conjunction with the Natural Resource Conservation Service (NRCS), to control sources of nitrate nitrogen and soluble ortho-phosphorus concentrations in White Clay Creek, especially agricultural non-point sources, wastewater treatment plants (especially in drought conditions), lawn fertilizers and atmospheric deposition (primarily for nitrogen).
  • Develop strategies, in conjunction with NRCS and municipalities, to reduce soil erosion into the streams, which comes from construction disturbance, urban runoff, agricultural nonpoint sources and streambank erosion.
  • Conduct tissue analysis on fish and invertebrates to discover whether the presence of zinc, PCBs and DDT represents a health risk to people and animals who consume the fish.
  • Confirm sources of the chemical pollutants zinc (possibly the former NVF plant in Newark), chlorinated pesticides (agriculture, including mushroom culture) and PCBs (unknown).
  • Increase the stringency of chemical application and licensing procedures to protect water quality.

Land-Use Effects - Goals

  • Mitigate the contaminating effects of runoff on the White Clay Creek.

Land-Use Effects - Key Actions

  • Work with communities and NRCS to develop innovative strategies for stormwater management, groundwater infiltration, control runoff and elevation of stream temperatures.
  • In conjunction with NRCS, establish wooded stream buffers to moderate temperatures, control floodwaters, stabilize streambanks, purify water, filter out sediments and contaminants and recharge groundwater.
  • Improve controls on point and non-point source pollution.
  • Encourage the use of site-specific BMPs for on-site sewage treatment and the evaluation of the cumulative impact of such developments.
  • Improve the management of landfills to reduce adverse impact on groundwater quality by monitoring surface runoff and leachate.

Water Balance - Goals

  • Maintain quality groundwater during dry seasons and reduce flooding.
  • Ensure adequate recharge of the aquifers.
  • Maintain water balance as close as possible to natural conditions.

Water Balance - Key Actions

  • Minimize new impervious coverage and vegetation loss to encourage adequate infiltration.
  • Develop innovative strategies for increasing infiltration rates within the watershed.

Inputs and Withdrawals - Goals

  • Minimize adverse impacts of wastewater treatment, including on-site domestic systems, on water quality in the White Clay Creek watershed.
  • Ensure adequate water quantity for intensive agricultural activities.

Inputs and Withdrawals - Key Actions

  • Monitor the creek's capacity to assimilate discharges from sewage treatment plants and industrial wastewater.

Droughts, Floods and Flow Maintenance - Goals

  • Maintain adequate stream flows during warm, dry weather for water withdrawal, habitat maintenance and aquatic fisheries.
  • Reduce high peak flows and flooding.

Droughts, Floods and Flow Maintenance - Key Actions

  • Design and carry out open space, groundwater and wetland conservation programs to maintain base flows adequate for aquatic habitat, fisheries and water-supply purposes.
  • Work with municipalities and landowners to enhance infiltration rates within the watershed.
  • Require and enforce stormwater management regulations that enhance groundwater recharge.
  • Promote artificial maintenance of creek base flows, especially during drought conditions, from any future (proposed) reservoir project.