Rick Shiver, Department of Environment and Natural Resources

1 March 2001

Surface water resources in NC are being stressed by the discharge of wastewater by the growing population of North Carolina. The capability of NC’s rivers to absorb this amount of discharge is being exceeded.

We are increasing the amount of urban area, with significant runoff from roofs, parking lots, road, etc. while decreasing the amount of acreage devoted to farming and forestry. The increased urban area increased runoff; the runoff includes nutrients, pollutants, and oxygen-demanding organisms.

Clean Water Act (1970)

The Act was passed as a way in which to clean up urban waters.

The Act requires that no degradation in surface water quality standards can occur

As a result of this act, all of the surface waters of the state were classified

The classification recognized that some surface waters were High Quality, while others were truly Outstanding

The Water Quality Standards Program requires that we use the water for its best (highest) use and that we need to protect each water type.

Classification of Water Quality

A—Highest quality (trout fishing [fresh water] and shellfishing [salt water])

B—Recreational use (swimming and other human contact activities)

C—secondary uses (boating and other non-contact activities)

S—is a prefix for salt waters; e.g. SA, SB or SC waters

Supplemental modifiers to the classification system

Tr—Trout stream

Sw—swamp systems

HWQ—high quality waters

ORW—outstanding resource waters

NSW—nutrient sensitive waters (e.g. Neuse and New Rivers)

FWS—Future Water supply

Bacteriological Standards

SA—less than 14 fecal coliform bacterial colonies per 100 milliliters

SB—less than 200 fecal coliform bacterial colonies per 100 milliliters

SC—greater than 200, but less than 1000 fecal coliform bacterial colonies per 100 milliliters

Water quality in the state is measured against the standards noted above in order to maintain public health and biological productivity

Water is continually sampled throughout the state with up to 400 samples taken monthly

We cannot allow water to degrade below the designated standards otherwise, the waterway is placed on a federal list.

Electrical Power generating plants are a major source of thermal pollution

Examples of these are the CP&L Sutton Plant in Wilmington and the CP&L Brunswick Nuclear Plant in Southport which passes 2 billion gallons of water per day.

International Paper Co. uses 50,000,000 gallons per day and empties 5,000 tons of BOD into the Cape Fear River each day. They are a major cause of lowered oxygen in the Cape Fear River.

Wilmington Wastewater treatment plants dump 20,000,000 gallons of water per day into the Cape Fear River. These plants are at their dumping limits and require a $50,000,000

expansion to treat more water.

Wastewater treatment of human sewage involves several processes:

remove solids from water

aerate the water to break down solids into CO₂ and H₂O

clarifier treatment removes solids

digestion breaks down the solids that have been separated from the water

Package plants—Small communities or subdivisions have these small sewage treatment plants

Water is returned to the ground or to surface streams. On barrier islands, the highly permeable sands do not allow materials to be cleansed. Pollution can enter the ground water system. Wells and sewage discharge systems are using the same sands; therefore the possibility of pollution of the groundwater is high.

Beaches now have sewer systems that allow the sewage to be moved to the mainland for treatment.

Septic tanks are appropriate in most locations with low water table. High water table prevents them from functioning properly.

Wetlands are superior for removing nutrients; in other words, wetlands treat water.

Unfortunately, we have a history of destroying (draining) wetlands.

The removal of wastes from hog farms is a problem. In Duplin County, there are 400 farms. Typically, the waste is removed to a holding lagoon and then sprayed onto fields but during Winter and other times when the water table is high, this spray moves by surface flow to waterways. So called "family farms" have up to 800 hogs per "house" and sometimes many houses per farm.

Coastal Stormwater Runoff

There are many waterways that are rated HQW and ORW in the coastal area. Rules in the coastal area determine that to maintain the water quality, we must either adopt low density development (30% cover or less) or control the first inch of rainfall and 85% of the sediments coming off the land. With these regulations, many lagoons have been established throughout the region.

The number one pollutant in the state and the nation is sediment.

Sediment smothers the biota

Oil spills are a problem on occasion, but usually are minor. These are extremely difficult to control and contain and much of the work of the regulatory agencies is to assess damage rather than attempt to control.

Water quality problems are manifested by fish kills. With increased nutrients in the surface waters, algae flourish and become very dense. When the algae run out of nutrients, there is typically a massive die-off of the algae. The decay of the algae results in an oxygen deficit and fish are not capable of surviving. Therefore, large fish kills occur.