Technical Reports

These publications were written with a scientific audience in mind. Less technical reports are also available.

City of Durham Stormwater Permit (NPDES Permit)

Because the city has a storm drain system that carries rainwater away from developed areas to creeks and lakes, we are required by the federal Clean Water Act to have a National Pollutant Discharge Elimination System (NPDES) permit.

This permit is the basis of many of the following documents. This permit is evaluated every 5 years to adapt to changing water quality needs and technological advances. The following link is for the permit from October 10, 2018 - October 9, 2023 (PDF).

NPDES Annual Report

The city provides the state with an annual report on stormwater management. This report is required by the city’s federal National Pollutant Discharge Elimination System (NPDES) permit.

• The report for the most current reporting year: 2019 - 2020 (PDF). 
• Archived reports from previous years

 
The report provides information about new initiatives and programs, compares collected data to water quality standards, and summarizes water quality investigations. It also outlines how the city met the minimum permit requirements in the areas of: public education and outreach, public participation and involvement, illicit discharge detection and elimination, post-construction runoff, municipal pollution prevention and good housekeeping, industrial inspection, and water quality monitoring and assessment.

Note: Beginning in 2007-2008, the reporting period changed from running July 1 through June 30 to running from October 1 through September 30.

Stormwater Management Plan

A stormwater management plan outlines how the city intends to meet the requirements of its minimum NPDES permit requirements including:

• Illicit discharge detection and elimination
• Industrial inspection
• Municipal pollution prevention and good housekeeping
• Post-construction runoff
• Public education and outreach
• Public participation and involvement
• Water quality monitoring and assessment

The Stormwater Management Plan is developed at the beginning of the permit cycle and revised each year based on conditions, ordinance revisions, etc.
Comments from the public on the SMP are always welcome. Send any comments to the Stormwater Quality Manager.

You can find our most recent SMP here: Stormwater Management Plan 2018-2019

Total Maximum Daily Load (TMDL) Response Plans

Section 303(d) of the Clean Water Act requires states to identify water bodies that do not meet surface water quality standards. A TMDL may be required when a water body is listed as impaired. A TMDL determines the maximum amount of a pollutant allowed to enter a water body so that water quality standards can still be achieved. The City of Durham is currently subject to a fecal coliform bacteria TMDL for the Northeast Creek watershed and a turbidity TMDL for the Third Fork Creek watershed. TMDL Response Plans were completed for both watersheds in 2019. The objectives of the TMDL Response Plans are to identify and implement measures that will reduce the levels of the targeted pollutants in Northeast Creek and Third Fork Creek. You can read the full plans at the links below. 

TMDL Response Plan for Northeast Creek
TMDL Response Plan for Third Fork Creek