Wastewater Spills in Southeastern North Carolina

The Environmental Impact & the Growing Need for Sound Infrastructure

By

Timothy Griesbauer

Legal Foundations of Coastal and Environmental Management

Fall Semester, 2005

University of North Carolina at Wilmington

Summary

Wastewater spills are problematic events for local municipalities that have repercussions that can be especially harmful to the environment and pose a significant risk to public health. According to the North Carolina Department of Environment and Natural Resources (NCDENR), there are more than fifteen thousand sewer overflows in North Carolina each year. There are manycauses that contribute to sewer system overflows:

  • Tree roots can find their way into sewer lines and create obstructions.
  • Foreign objects can be dropped in sewers and manholes.
  • Failure to properly dispose of grease and other such materials.
  • Excessive rainfall causing an overloadof sewer lines or pump stations malfunctioning due to electrical or mechanical failure.

Additionally, one other major cause of sewage overflows is worn infrastructure that is in need of replacement. In 2005 several areas in southeastern North Carolina experienced significant wastewater spills as a result of failing infrastructure, most notably the port city of Wilmington. The problems experienced by the magnitude of these infrastructure failures were unlike anything the city had ever seen before with prior wastewater system malfunctions. Each spill had a significant short-term impact on the local environment and also moved the issue of infrastructure repair and replacement to the forefront of the city’s agenda. The spills began in July with a massive spill into the Hewletts Creek watershed.

Hewletts Creek: The First Spill

Hewletts Creek covers portions of central and eastern Wilmington, NC and also borders the Atlantic Intracoastal Waterway. Approximately ten miles long, the creek spans 6,537 acres that cover 9.28 square miles.[1] The creek is home to spartina alterniflora that vegetate along the creek edge and around the lower marshes and Juncus roemerianus which are located in the higher marshes. The creek is also designated as a “primary nursery area” by the N.C. Division of Marine Fisheries and has supported shellfish harvesting for many years. Additionally, it is one of the most developed creeks in NewHanoverCounty. Forty-six percent of the area is classified as residential while only twenty-eight percent is undeveloped. Areas of the creek that are developed but are not classified as residential include areas used for commercial purposes, roads, and for the PineValley and Wilmington Municipal golf courses.

At 6:00am on Friday, July 1st, 2005, City of Wilmington officials were notified by the Wilmington Police Department about a force main break near the sewage pump station in the vicinity of Pine Grove Drive and Greenville Loop Road. The police were informed of the break through a telephone call from a local citizen. The break in the main, which carries millions of gallons of sewage coming from various smaller lines in Wilmington, Wrightsville Beach, and much of eastern New Hanover County to the Southside treatment plant on River Road each day, caused a massive spill of raw, untreated sewage into the Hewletts Creek watershed which lasted approximately eighteen hours from 5:00am to 11:00pm. City officials,classifying the spill as “significant”, originally estimated it to be around one million gallons,leaking into the creek at a rate of about 56,000 gallons per hour. However, the spill was much bigger than originally thought. In actuality, three million gallons of sewage were spilled into the creek at a rate of 167,000 gallons per hour, making it the biggest wastewater spill in the history of the city and far more serious than “significant”. By comparison, the amount of sewage spilled into the creek was approximately twenty-seven percent of the total amount of oil spilled by the Exxon Valdez in Prince William Sound off the coast of Alaska in 1989.

Repair crews responded quickly to the spill, arriving on site shortly after the city was notified. Power to the pump station was shut off at 10:00am, but raw sewage continued to flow because the city didn’t have an alternate route to direct the wastewater toward the Southside treatment plan. The cause of the spillwas found to be the result of a stainless steel coupling that failed which held two 24-inch sections of the main together. The coupling was replaced with the exact same type of coupling that had failed in order to stop the flow. The city replaced the temporary coupling with a permanent, sturdier device on August 9th, 2005. According to city officials, the city’s sewer service was not affected and the water supply was not threatened despite the severity of the spill.[2]

Environmental Impact

The spill had a tremendous impact on the environment. An investigation of the Hewletts Creek watershed conducted by boat just after the high tide and by vehicle on July 3rd, 2005 by UNCW scientists Mike Mallin and Doug Parsons found there to be numerous visible effects[3]. Exploring up to about the halfway point of the main channel of the creek, they encountered numerous dead fish, some being fed on by crabs and birds, including mullet, eel, flounder, sunfish, menhaden, and numerous other small fish species. Overlooking the creek from a vehicle on a bridge, they counted over two hundred dead fish. They suspect that there were many other dead fish that could not be counted because of the geography of the creek and lack of available access to many portions of it. In addition to the dead fish, many waterfowl also died as a result of feeding on the dead fish. Algal blooms also appeared in large numbers as a result of the spill. The blooms are caused due to the high levels of nitrogen and phosphorous found in the water from the bacteria. The blooms will have an impact on available space in the creek to fish and shellfish. When the blooms die, they turn into a kind of “organic mush” which will then serve as food for bacteria in the water. The bacteria will multiply and will use additional amounts of dissolved oxygen in the water. This results in less dissolved oxygen available to fish and shellfish.[4]

The scientists also investigated oxygen and bacterialevels present in the creek. Dissolved oxygen levels, which support aerobic life forms and should ideally hover around 5 milligrams per liter[5], were measured at 1.9 milligrams per liter, reflecting the impact of the algal blooms. Samples taken from the lake showed fecal coliform levels as high as 270,000 colonies per 100 milliliters of water. Safe levels for swimming[6], as outlined by the North Carolina Division of Water Quality (NCDWQ), are 104 colonies per 100 milliliters of water for a single sample. That is 2,600 times higher than the state regulated level. Subsequent samples taken from the water of the creek over the next few days showed that this extremely high concentration of bacteria reduced quickly. The effects of sunlight and the natural flushing action of tidal forces are the main reasons for this significant drop. According to Dr. Mallin, water sample results from a test taken on August 8th, 2005, a little over a month after the incident, show that “contaminant levels are within the state’s safe-water standards.”[7] However, the longer term impact of the bacteria in the environment is not immediately known due to the fecal coliform settling down into the sediment that makes up the bottom of Hewletts Creek. Dr. Larry Cahoon of the UNCW Biological Sciences Department said concentrations of bacteria in the sediment remained high in the days immediately following the spill and it was unknown how long it would take for the bacteria to naturally work its way out of the bottom.[8] Testing of sediments nearly two weeks after the Hewletts Creek spill found bacteria levels that ranged from three to 30 times normal levels.[9] Mallin added that, despite the safe water levels, it would not be recommended to wade in the creek specifically because of the bacteria in the sediment. Any disturbance of the bottom would “kick up” the bacteria that had settled and make the water unsafe again.

The NCDENR issued an advisory the morning of the spill warning the public against swimming in Hewletts Creek due to the potential public health risks that could result from doing so. The Department warned that “adverse health effects such as diarrhea, abdominal cramps, and skin defections” could occur if people swim in these contaminated areas. Additionally, the spill resulted in the closing of all waters between the WrightsvilleBeachBridge and the Intracoastal Waterway near Peden Point for fishing, shellfishing, and swimming purposes.[10] The NCDENR lifted the swimming part of the advisory from the Wrightsville Beach Bridge to Peden Point on July 11th, 2005[11]and for the downstream portions of Hewletts Creek on July 26th, 2005[12] due to analysis of water samples in both areas that showed that bacteria levels had dropped below the state and federal standards set for swimming and water play.

The NCDWQimposed a $51,491.84 fine on the City of Wilmington on August 9th, 2005. They cited four reasons[13] for the fine:

  • Making an outlet to waters of the state without a required permit
  • Failure to properly maintain the collection system
  • Impairing use of the public’s waters for shellfishing and recreation
  • Enforcement costs which cover staff time, materials, or other costs accrued during the investigation

The fine was the second largest in state history for a wastewater spill behind the $65,414.81 fine assessed to ElizabethCity on the same day for its 5.6 million-gallon sewage spill back on May 3rd, 2005.

Hewletts Creek: The Second Spill

During the morning hours of September 15th, 2005, just eleven weeks after the worst sewage spill in the city’s history, the same force main that broke and sent three million gallons of raw sewage into Hewletts Creek ruptured again, this time spilling approximately 905,000 gallons of raw sewage onto Shipyard Boulevard and into many ditches and yards along Pine Valley Dr. At 10:00am, the city was informed of the spill again by a local citizen who in this case just happened to be passing by. The city had crews working to repair the spill by 10:30am. A berm, a raised bank that serves as a barrier, was formed by the repair workers in an attempt to keep the waste from spreading so they could then pump it back into the sewage system. However, the berm failed and raw sewage continued to spread, including over the parking lot of the Pine Valley Church of God. By 9:00pm that evening, the flow was contained and the sewage had been pumped back into the sewer system. City officials again maintained that the sewer service was not interrupted as a result of the spill and that there was no threat to drinking water. The heavy rains that poured down on the city as a result of Hurricane Ophelia were the reason cited for the spill. The main became overwhelmed by the amount of wastewater flow and a section of the pipe that had extensively corrodedthen burst, causing the spill. Most of the sewage again found its way into Hewletts Creek by way of drains that empty there.

The environmental impact of this second spill was not as severe as the first spill due only to a far less of amount of raw sewage that was spilled, but the effects were similar. Numerous fish were again killed as a result of the toxic water in the creek. Water samples were taken the morning after the spill and showed fecal coliform bacteria levels to be 31,000 colonies per 100 milliliters of water. This amount of bacterial pollution is approximately 300 times the state regulated level for swimming, far less severe than the samples taken immediately following the first spill, but still at an extreme level. However, the NCDENR did not issue a swimming advisory for this spillbecause the pollution did not spread to recreational swimming areas. Additionally, the NCDWQ did not impose any sewage violation fines on Wilmington for this spill as they did with the first spill. The reason why no fine was assessed is not known.

Other Notable Spills

The two sewage spills in Hewletts Creek received a lot of press coverage and attention, but they are not the only spills Wilmington and the surrounding areas of southeastern North Carolina have dealt with in recent memory. Within approximately one month of the second Hewletts Creek spill in Wilmington, three other major spills occurred.Two occurred on September 27th, 2005; a break in the force main around the area of Plantation Landing Drive in NewHanoverCounty spilled 11,700 gallons of sewage into Futch Creek and a separate break in NewHanoverCountyspilled 20,000 gallons of sewage into BradleyCreek. These spills prompted swimming advisories from the NCDENR as well. The other spill of note was a third major spill for Wilmington in four months time. Only weeks after the second Hewletts Creek spill, a wastewater line near the intersection of River and Brian Roads broke which caused yet another major spill. This time, 15,000 gallons of sewage leaked into the Cape Fear Riverby way of a storm drain. The city’s director of Public Utilities, Hugh Caldwell, noted that having three broken sewer lines within a few months was not common, saying “It’s been an unusual summer for us.”[14]

Areas of BrunswickCounty are also experiencing problems with sewage spills. Most of the spills have been minor, but come as the result of a failure to get residents to integrate into new central sewage systems being implemented in the county. As a result, old septic systems are continuing to leak, outright failingin some instances,and are spilling onto the ground and in local waterways. In addition to the age of these septic systems, many recent failures have been attributed to the stresses caused by tropical storm activity. Tropical Storm Tammy was the cause of a sewage spill at BaldHeadIsland’s sewage treatment facility, resulting in approximately 10,000 gallons being spilled as well as a spill at the CarolinaShores sewage treatment facility, resulting in approximately 4,000 gallons spilled. Hurricane Ophelia was the cause of a nearly 3,000 gallon spill that was isolated primarily inside the residence of one BrunswickCounty woman.[15] Ms. Ingrid Larson’s home was flooded with raw sewage as the result of the lack of a back-flow prevention system that should have been installed on her plumbing. The spill effectively destroyed her home and most of her possessions.

The Infrastructure Problem

“The concerns were always there. It’s just unfortunate that it took something of this magnitude to see how bad the system was failing in certain areas.”

-Ted Wilgis, CapeFear Coastkeeper[16]

All the wastewater spills that have occurred in this region over the course of the last year represent a growing problem with the area’s infrastructure. Quite simply, a growing number of pipes, pump stations, and other important parts of wastewater treatment systems in the area are beginning to show signs of aging, resulting in the failures that are leading to these kinds of spills. It’s probable that the central reason why these systems have been allowed to deteriorate is due to simple neglect and ignorance on the part of decision makers.

Wilmington City Councilman Jim Quinn stated after the second Hewletts Creek spill that the pipes that had failed were “supposed to last another ten years or longer.”[17] However, before Wilmington had its massive sewer system woes in 2005, their system was one of twenty-five statewide identified by the NCDWQ in a 2004 report as “problematic”.[18] City leaders did not necessarily ignore the report when the findings were released, but they did not make the findings an immediate budgetary priority either. Long-range sewer-related projects were planned for the city that are designed to significantly upgrade the infrastructure to provide sound, clean wastewater service for the future, but these projects are included in budgets beginning in 2009-2010.[19] The projects involved are part of a five-year capital improvements program that will include more than thirty new public utilities estimated to cost approximately seventy-seven million dollars. Included in these projects are planned upgrades to the Southside wastewater treatment plant at an estimated cost of 15.4 million dollars and an expansion of the Sweeney water treatment plant at an estimated cost of twenty million dollars.[20] The City has acknowledged after the fact that this timetable needs to be accelerated in order to properly address these sewage spill issues. Another project the city has proposed is the construction of a new secondary force main pipeline that would run parallel to the nine-mile system which failed resulting in the Hewletts Creek spills. Several years ago, this project was estimated to cost in the neighborhood of five million dollars, but the costs are likely to have gone up over time. After the construction of this proposed project is complete, the plan would be to use both the old and new pipes at the same time to regulate wastewater flow.