Nonpoint Source Pollution

Determining nonpoint source pollution is important in eliminating it. The informative table below lists some sources of pollution, their impact on the environment, and proposed solutions which are useful in conjunction with those outlined in the EHS Storm Water Management Program.

Pollution Source	Impact	Solution
Soaps and detergents to wash vehicles	All detergents destroy the external mucus layers that protect fish from bacteria and parasites. They also lower the water's surface tension, making pesticides and chemicals more easily absorbed by the fish. Some detergents contain phosphates that promote algae growth. When algae decomposes, it uses up the available oxygen of aquatic life.	Wash with plain water Use biodegradable soaps and wash over large grassy areas Wash car at a car wash that is connected to sanitary sewer lines
Silt and sediment from construction sites	Sediment collects in drinking water reservoirs, leaving less room for water storage. Sediment and grit also smother bottom dwelling aquatic life, clog fish gills, and block sunlight needed by underwater plants.	Innovative and site-specific BMPs Stricter monitoring and education programs
Cleared vegetation, tree trimmings, grass clippings, leaves, and acorns	The debris clogs storm sewers, which increases the risk of flooding. Large collections obstruct water flow and cause creek bank erosion. As this organic matter decomposes, it uses up the oxygen intended for aquatic life survival. Decomposing organic matter also creates foul odors and taste in drinking water.	Sweep leaf litter and collect in bags. Recycle matter for compost More frequent street sweeping
Excessive irrigation	Transports fertilizers, pesticides, dirt and grime to local storm sewer or waterway. Fertilizers and pesticides can kill aquatic life. Oil can contaminate drinking water.	Fix malfunctioning sprinklers and faucets Water only when necessary and for appropriate amounts of time
Hazardous and non-hazardous materials discarded in unprotected dumpsters	Creates danger to sanitation workers emptying the dumpsters. If these materials escape, they are transported through the soil or a storm sewer to Waller Creek where they can severely affect aquatic life and render water unusable for drinking or recreation.	Restrict dumpster access to trained personnel Assure drain valves are functional Protect all dumpsters from rainfall with either covers or overhead roofing All materials in dumpsters should be bagged or in containers
Dirt, oil buildup, and accumulated debris cleaned from walkways and drives	Cleaning agents can provide nutrients that promote the growth of algae. The blooms deplete sunlight available to aquatic life. Then, as it decays, the algae use up the oxygen available for aquatic life to survive.	Improved maintenance of vehicles Placing strips of absorbent material (i.e. Astroturf) where cars park frequently More frequent street cleaning
Misuse/overuse of fertilizers	Fertilizers contain large amounts of nitrogen and phosphorus- primary nutrients for algae. As it decays, the algae use up the oxygen necessary for aquatic life to survive. Some fertilizers also release ammonia, which is toxic to fish.	Limit the amount of fertilizer used. Use of drop spreaders instead of broadcast method The City of Austin Grow Green Program
Misuse/overuse of pesticides	While designed to destroy pests, "broad spectrum" pesticides also poison "good bugs," birds, and other wildlife. Also seeps into groundwater and contaminates drinking water, and destroys soil by killing essential organisms from microbes to earthworms. Some pesticides are also toxic to humans.	Protect storm sewers and areas not needing treatment Substitute with nontoxic products Use sparingly and only as a last resort. Follow the instructions; more is not better
Poorly maintained dumpsters	Liquid wastes can drip out, leach into groundwater, and enter creeks. Un-bagged trash is easily carried to storm sewers and waterways by wind or rain. Open or overfilled dumpsters easily allow wind or rain to carry trash to waterways. Trash and debris clog storm sewers and waterways, which may cause flooding. Dumpsters in poor condition attract flies and rodents whose waste contaminates collected rainwater that cannot be discharged to creek.	Get lids to cover dumpsters Build roofs over dumpsters Limit dumpster access to trained personnel
Erosion of land from student traffic	Concentrated student traffic kills plant life that keeps soil stable. When soil is exposed, it is susceptible to wind and water erosion allowing sediment to enter creek, which smothers aquatic life.	Use ground cover over areas next to buildings and under trees that do not provide enough light for plant life Install railing along stairs that discourage students from cutting across grass Install decorative stones in corners between sidewalks Study traffic flow and install sidewalks or small stone paths in most traveled areas
Custodial waste	Mop water, floor wax, cleaning agents, and painting equipment wash water often kill plant life when dispersed on grass. The plant life holds the soil in place preventing erosion. Waste entering storm drain is toxic to aquatic life and can render water unusable for drinking.	Restrict use of agents to trained personnel Contain wash water and dispose of properly. Non-hazardous agents may be discharged into sanitary sewer system upon EHS approval
Delivery Trucks	Cutting corners on access ways and having to turn around destroys vegetation and leads to erosion. Trucks parking under trees put more pressure on the roots that kills the tree and causes erosion once the tree is removed.	More loading zone parking provided by transportation Pylons and chains to prevent shortcuts
Litter	Particularly plastic items that float, spoil the beauty of creeks and lakes and can be harmful to fish and birds that mistake them for food. Litter can also clog storm sever lines increasing the risk of property damage from flooding.	More recycling bins Volunteer litter pickups