Stormwater is rainfall or snow melt that flows across surfaces into waterways. It is North Carolina’s top water-quality problem. Stormwater is not treated and often picks up pollutants as it moves across surfaces, like exposed soil, pavement and rooftops.

Pollutants include:

• Chemicals, oil and grease
• Excess fertilizer and pet waste
• Sediment and trash

The pollution can harm aquatic ecosystems and drinking water supplies. Hillsborough's drinking water comes from the Eno River.

Documents

• Climate Impact — Rainfall intensity's effect on flooding
• Do You Like to Fish — Stormwater runoff pollution and its effect on fish

Hillsborough must adhere to stormwater runoff regulations from the federal and state governments.

Federal Regulation

Stormwater is regulated under the 1972 Federal Water Pollution Control Act, commonly called the Clean Water Act. The Environmental Protection Agency regulates discharges through the National Pollutant Discharge Elimination System. Discharges include stormwater.

State Regulation

Within the state, the N.C. Department of Environmental Quality operates the stormwater program for the National Pollutant Discharge Elimination System.

Under Phase II of the rules, small municipalities that own and operate separate storm sewers must obtain a permit and reduce stormwater pollutants from entering their systems through six minimum measures.

The minimum measures for Hillsborough are:

• Public education and outreach on stormwater impacts.
• Public involvement and participation.
• Illicit discharge detection and elimination.
• Construction site stormwater runoff control (erosion control).
• Post-construction stormwater management for new development and redevelopment.
• Pollution prevention and good housekeeping for municipal operations.

Hillsborough is required to regulate runoff within town limits.

See the effect of stormwater runoff pollution on businesses in the document Don't Go Down the Drain. 

See the Public Infrastructure Permits page for:

• Construction and post-construction stormwater management requirements and applications.
• Information on riparian (stream) buffers and stream identification requests.

Town Stormwater Plans

• Bellevue Branch Watershed Improvement Plan
• Stormwater Management Plan

Report any suspected stormwater pollution or illegal dumping into the town's stormwater system.

It is illegal to:

• Place anything other than stormwater into any part of the town’s stormwater system, including storm drains and ditches.
• Connect pipes to the town’s stormwater system without approval.

Illegal Dumping

Signs of illegal dumping:

• Excessive algae
• Floating debris
• Oil sheen
• Strong pungent or musty odor
• Storm pipes flowing in dry weather
• Surface scum or foam
• Unusual color or cloudiness

Examples of illegal dumping:

• Chlorinated backwash or the draining of swimming pools
• Contaminated foundation drains
• Oil, antifreeze, chemicals, garbage, paint or cleaning fluids
• Sewer and septic tank discharges
• Untreated animal waste
• Wash waters from commercial and industrial activities
• Washing machine discharges

Required Detection

The town is required to find and eliminate stormwater pollution. If an illegal connection or discharge is found, the property owner will be notified. The owner could face civil penalties up to $5,000 if the issue is not corrected.

In North Carolina, common law governs stormwater runoff and drainage. Basically, a downhill property has to receive water from uphill. Water has a right to go where it wants to go ― downhill.

Components of this common law:

• The easement of an uphill owner includes the right to accelerate and increase the natural flow of water.
• Natural flow means the uphill owner cannot divert or cause water to flow onto the lower land in a different manner or place than it would naturally.
• The downhill owner may not obstruct natural flow from above.

Property owners have the legal right to make reasonable use of their property, even if development alters water flow and affects downstream owners. The uphill owner can incur liability when the change in runoff is unreasonable and causes substantial damage. 

Documents

• Stormwater Runoff Conveyances
• Water Flows Downhill

Property owners are responsible for the stormwater control measures on their private property. Owners include homeowners associations.

Drainage Ditches Along Streets 

Property owners are required to mow drainage ditches along town streets.

The town ensures water flow is not restricted in the drainage ditches along town streets. Contact the Public Works Division to request maintenance of drainage ditches.

Wet and Dry Ponds

Property owners are required to have wet and dry ponds inspected annually by a private licensed inspector. The inspection report must be submitted to the Stormwater and Environmental Services Division. 

The third-party annual inspections may result in recommendations for maintenance or improvements. Before making a costly repair, contact town staff to check that the work is necessary. See the Wet Ponds and Geese section if a recommendation involves addressing geese.

The town enforces a 50-foot buffer of plantings along streams and the Eno River. Prior approval is required to clear, build or make other impacts within a stream or river buffer, also called a riparian buffer.

• See the Public Infrastructure Permits page for additional information and to request stream identification services.
• See Riparian (Stream) Buffers.

About Stream and River Buffers

Buffers along water bodies are undisturbed, naturally forested areas that:

• Provide wildlife food and habitat.
• Slow stormwater runoff by allowing it to soak into the ground.

Buffers help protect water quality by:

• Controlling erosion and keeping stream banks from collapsing.
• Reducing flooding and pollution of waterways.
• Moderating stream temperature through the amount and quality of sunlight allowed on a waterbody.

Woody debris in waterways also protect water quality and provide habitat for aquatic organisms. See the document Woody Debris in Streams and Rivers.

The division offers materials to help property owners manage stormwater and protect the environment. Contact staff to request a site visit and advice.

Documents

• Compost Blankets
• Designing A Rain Garden
• Don't Go Down the Drain — effect of stormwater runoff pollution on businesses
• Lawn Care For Water Quality
• Stormwater Bioswales
• Stormwater Runoff Conveyances
• Water Flows Downhill
• Woody Debris In Streams And Rivers

Websites

These sites were created in partnership with Elon University students:

• Enhance Your Yard with Green Infrastructure — Focusing on water management that works with the natural water cycle. 
• Climate Impact in Residential Areas — Spotlighting the effects of climate change on the local area and actions community members can take.

Videos

• Rain Garden

Annual Herbicide Treatment

The state treats the Eno River annually to reduce the invasive plant hydrilla. The town helps fund the treatment through stormwater fees. See the About Water page.

Educational Programs

The town partners with Orange County to provide educational programs and presentations. Topics include:

• Preventing stormwater pollution
• Maintaining stormwater ponds
• Other best practices

Programs typically are provided for civic, school and local watershed groups, elected officials, developers, contractors and other groups interested in learning more about stormwater issues. 

Contact stormwater staff to request a program or presentation.

Other Partnerships and Opportunities

Clean Water Education Partnership — The town is a supporting member of this partnership to protect water quality in the Tar-Pamlico, Neuse and Cape Fear river basins. Hillsborough's watershed is part of the Upper Neuse River Basin. The partnership is a cooperative effort among local governments, state agencies and nonprofit organizations. It uses education and outreach to protect water quality.

Eno River Association — The town partners with the association in preserving and conserving lands along the Eno River. Community members can join the association's stream monitoring program to help protect the local watershed.

Volunteer Workdays — Stormwater staff offer volunteer workdays at parks, wetlands and other areas around town. Subscribe to town news releases.

Annual Reports

Falls Lake Nutrient Sensitive Water Report — The report summarizes efforts related to new and existing developments in the previous fiscal year (July 1-June 30). It is required by the N.C. Department of Environmental Quality under the Falls Lake Stormwater Rule for New Development.

• Falls Lake Nutrient Sensitive Water Annual Report

National Pollutant Discharge Elimination System Phase II Report — The report summarizes activities of the town’s stormwater management program for the previous fiscal year (July 1-June 30). It is required under the federal Clean Water Act and state regulations. 

• National Pollutant Discharge Elimination System Phase II Annual Report

Stormwater Almanac

The division periodically publishes the Stormwater Almanac with news and information on the division's recent projects.

• Stormwater Almanac

Awards received by the division include:

Green Infrastructure Project of the Year ― For the Odie Street bioswales project from the Stormwater Management Division of the American Public Works Association North Carolina Chapter in 2023.