A Report on Water Quality to the Citizens of Durham The State of Our Streams: 2008 The 2008 calendar year brought new types of monitoring to the City of Durham. Leveraging agreements with other agencies, the City has been able to add streamflow and Help Stop Stormwater Pollution! rainfall data collection within the City. In Call 560-SWIM to report anything in cooperation with the U.S. Geological Survey, creeks or storm drains that is not water! six stream stage monitors and rain gauges were installed across the City. A subset of these includes stream flow. These to report results, this is a significant monitoring stations allow City staff to improvement to our understanding of evaluate the effects of stream flow on water Durham streams and may provide another quality and provide citizens with improved way to track improvements resulting from information regarding the potential for flood stormwater management. damage. In cooperation with NC State University, a fully functional weather station The 2008 calendar year also completes the was installed as part of the statewide ECONet fifth year of monthly water quality climate network. This station offers real- monitoring. Having five years of information time measurements of rainfall, air allows City staff to evaluate if water quality temperature, wind, and pressure. There is has been improving or worsening over the no longer a need to rely on information from last five years. Although the environment the Raleigh-Durham Airport, which is over 10 responds slowly to small changes, City staff miles away and often out of sync with what were able to note both improving and is happening in the City. The rainfall and worsening of various water quality stream stage monitoring began in July 2008, parameters over the last five years. These in time to catch the rainfall from Tropical are indicated in the watershed pages. Storm Hanna in September 2008. Rainfall totals ranged from 4.31 inches at City Hall to 6.32 inches at Cole Mill Road near the Eno State Park. Other recently implemented monitoring includes evaluations of changes to stream structure, such as streambank erosion. Streambank erosion can alter natural stream banks until a stream has “walls” on either side. The stream then appears to be cut into the landscape. Although it is still too early Anything that is poured or thrown into a storm drain goes into our creeks and streams. Stormwater does not receive treatment ! Stormwater Services staff member evaluating Crooked Creek (Cape Fear River Basin) City of Durham Stormwater Services—(919) 560-4326 www.durhamnc.gov/stormwater Design/Plan Review—Drainage/Flooding Concerns—Floodplain Information Stormwater Public Education—Surface Water Quality The State of Our Streams: 2008 Investigations Looking back at the last four reporting In addition to pollution associated with periods, the number of investigations finding storm water runoff, illicit discharges are pollution has remained relatively stable another source of pollution in urban areas. since 2005-2006. For the last three Illicit discharges are those discharges that reporting periods, between 130 and 160 occur without city, state or federal investigations have found pollution sources. knowledge of environmental impacts. Illicit Citizens and City staff have become more discharges include a variety of acts generally aware of potential water quality problems resulting in illegal dumping. For example, pouring oil into storm drains, disposing of and inappropriate reporting occurs less now pet wastes in the storm drains, discharges than in previous years. Also, the adoption from failing septic systems and leaky of the Stormwater Management and sanitary sewers, overflows from clogged Pollution Control Ordinance in 2006 has sanitary sewer systems, and direct provided citizens and staff with the connections of private sanitary sewer laterals assurance that once problems are found, to stormwater pipes instead of sanitary there are mechanisms to get problems sewer pipes are all illicit discharges. fixed. The number one source of pollution between Number of Water Quality Investigations October 2007 and September 2008 was Identifying Pollutant Sources, 2004—2008 sanitary sewer overflows from publicly owned works. A total of 54 investigations 200 identified sanitary sewer overflows as a source of water pollution. Fifteen 150 investigations identified private sewer lateral 160 146 leaks and overflows as sources of water 100 130 pollution. Twelve investigations identified 97 erosion and sedimentation as potential 50 sources of instream sediment and turbidity. 0 Sources and Types of Pollution Found 2004-05 2005-06 2006-07 2007-08 in 2008 The number of water quality 146 investigations that identified pollution sources, 2007-2008 Horton Rd Sewer Spill (Eno River Watershed) City of Durham Stormwater Services page 2 The State of Our Streams: 2008 The City has limited staff and resources to The water quality index can also be used to improve water quality. Therefore, it is identify target areas for clean-ups and to essential that citizens become involved and identify the potential for new pollution provide additional eyes, ears, and noses to sources that need to be investigated. help find and eliminate sources of pollution. The index provides a water quality grade that ranges from 0 to 100 relative to other Water Quality Monitoring Program streams in Durham County. All urban Federal permitting regulations require the streams generally fail to meet at least one City of Durham to monitor water quality in federal or state water quality standard, so all local streams. Stormwater Services staff urban streams fail in some manner. collect water samples from streams However, the water quality index allows throughout the city on a regular basis. citizens and Stormwater Services to identify Analyses of these samples includes those areas with the most serious pollution biochemical oxygen demand, nutrients, issues. sediment and metals. Fecal coliform bacteria is also analyzed regularly. These measurements allow City and State staff to evaluate potential risks to people, drinking water supplies and aquatic resources (e.g., 2008 Water Quality Index Results fish, waterfowl). The water quality index results for 2008 are summarized in Figure 1. Red indicates the Stormwater Services staff also collect aquatic poorest water quality. At the other end of the life to learn about water quality. Aquatic color range, dark green shows better quality organisms, or benthic macroinvertebrates, water. Between the extremes is a range of are collected annually to learn which streams conditions: yellow-green indicates some no longer support the insects that should be pollution, while light orange through dark present if the watershed was minimally orange indicates increasing pollution. disturbed. Streams may be rated Poor, Fair, Good-Fair, Good or Excellent. An Excellent Colored areas in the map correspond to the rating indicates the best insect community area that contributed to the index result. and water quality. These areas are called watersheds and indicate the land area contributing water and In 2008, the Stormwater Services staff pollution to the stream. In general, conducted a combination of chemical and stormwater runoff from highly urbanized microbiological monitoring at 45 locations. watersheds (e.g., downtown and older areas Aquatic life monitoring is conducted at 14 surrounding downtown) degrades water locations in and around the City of Durham. quality more than sparsely developed or rural areas. Water Quality Index Similarly, results for fecal coliform bacteria To provide an overall picture of the health of are summarized in Figure 2. A similar color our streams, Stormwater Services combines gradation is provided to distinguish more many of the chemical measurements of polluted areas from less polluted areas. water quality into a water quality index. The water quality index is like a numerical grade for our streams. Looking at this grade from The water quality index summarizes year to year can indicate overall progress in chemical data collected at 29 locations in cleaning up area streams. and around the City of Durham. City of Durham Stormwater Services page 3 The State of Our Streams: 2008 City of Durham Stormwater Services page 4 The State of Our Streams: 2008 City of Durham Stormwater Services page 5 The State of Our Streams: 2008 Explanation of watershed attachments Fecal coliform bacteria are directly measured and have two North Carolina water quality In order to provide additional information to standards, a geometric mean of 200 colony citizens, attachments were created for the forming units (cfu) per 100 milliliters (mL) primary watersheds in the City of Durham. and the number of exceedances of 400 These attachments provide a description of cfu/100mL. Ratings are as follows: the watershed, a historical look back on Good: Meets both state standards water quality for the last five years, and a Fair: Meets geometric mean standard description of water quality during 2008. Poor: Does not meet either standard Water quality information is summarized Stormwater Services staff receives more using non-technical terms, as follows: citizen questions regarding harmful bacteria than any other water quality parameter Aquatic life (Insects or benthic macro- monitored. As such, the State of Our invertebrates): This parameter is a direct Streams report provides the Bacteria/ measure of the variety of organisms found in Recreation indicator as a service to citizens City streams.