Keeping Stormwater Runoff Clean

Tips for:

Lawn & Garden

Sidewalks & Driveways

Septic System Users

Controlling Runoff

Even More Tips
Prepare your Home Before it Rains

Tips for lawn and garden

If pesticides and fertilizers are applied incorrectly or excessively, they can be washed from yards and gardens into waterways and groundwater. Pesticides can be toxic to fish and can contaminate drinking water. Chemical and organic fertilizers both can cause excessive plant growth in water. When these plants die, they rob the water of oxygen and this can kill fish.

Water and fertilize wisely and use pesticides only when necessary.

Encourage insect-eating birds and "friendly" insects like ladybugs and lacewings. Attract birds by providing tree cover and food during winter.

Compost your yard wastes. Keep grass clippings out of ravines and waterways where they will become unwanted fertilizer.

Believe the directions on pesticides and herbicides. Applying more chemicals than directed may do more harm than good. Never spray near ditches, lakes or streams. Spray on cool windless days.

Dispose of lawn and garden chemicals carefully. Follow instructions on the container. Never dump them down the drains, in the gutter or near water. They can "upset" sewage treatment plants and septic tanks. If you have unused pesticides, visit the Household Hazardous Waste web page for instructions on proper disposal.

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Tips for sidewalks and driveways

Streets and driveways are sources of water pollution. Oil leaking from cars is a major cause of water pollution. Spilled or leaked antifreeze kills fish when it reaches streams. Remember, most of the water from your driveway and sidewalk flows directly into streams without treatment.

Recycle your used crankcase oil. You can refer to Kitsap County's Solid Waste Division for information on the nearest collection center.

Fix that leaky crankcase or transmission. If repair is not possible, put a drip tray under the car and recycle the collected oil.

Pave your driveway with lattice block pavers instead of concrete or asphalt. These pavers allow stormwater to seep into the ground.

De-ice with sand instead of salts and chemicals. Sweep up the sand before the next rainstorm.

Keep suds out of the gutters. Use low-phosphate soaps when you wash your car. Wash your car on the lawn rather than the driveway. Soap in limited amounts will not harm your lawn but is extremely harmful to fish and other aquatic life. Do not dump detergents or cleaning compounds into local waterways.

Never direct wash water from engine degreasing into storm drains or ditches.

Sweep walkways and driveways rather than hosing debris into storm drains.

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Tips for septic system users

A septic system that works properly will treat sewage and then let the liquid effluent slowly soak into the soil. A system that doesn't work properly can pollute surface and ground waters and cause disease and odors.

Be careful what you flush. Don't flush oil, plastic, diapers or anything else that won't decompose. If you have a food disposal in your home, use it sparingly and have your septic tank inspected for pumping more often.

Know where your septic system is and protect it. Don't pave or drive over it or you may damage the tank and drainfield.

Have your tank inspected for pumping every three years. If it needs to be pumped, use only properly licensed septic pumpers.

Conserve water. Using more water than necessary will decrease the life of your system.

Divert runoff away from your drainfield. Excess water over a drainfield saturates the soil and can lead to failure.

Many of the newer septic installations have pumps, alarms, and timers. These systems should be serviced regularly by Health District certified companies.

If you have any questions regarding septic systems, contact the Kitsap County Health District at 337-5235 or visit the Health District's web site.

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Tips to control runoff

Removing vegetation or covering the ground with pavement and buildings prevents water from soaking into the soil. During rainstorms, this water flows across the ground, picking up oil, pesticides, fertilizers, grit or anything else that will float, dissolve or be moved along. These pollutants are carried into surface and ground water.

Retain natural ground cover whenever possible.

Stabilize areas of bare soil with vegetation as soon as possible after grading.

Plant more trees and shrubs. They capture and hold a lot of rain before it reaches the ground. Wherever possible, keep existing trees, bushes and plants.

Avoid landscaping plastic. Large plastic sheets used to prevent erosion or weeds create as much runoff as paved streets. Use burlap on hillsides and perforated landscaping fabrics on level areas.

Limit use of bark mulch. It creates toxic leachate that may enter water courses. Limit use of bark mulch to areas that do not drain directly into storm sewers or open water.

Don't connect roof downspouts to ditches or storm sewers. Direct the water over lawns or construct French drains (gravel-filled trenches) whenever possible.

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Even more tips

Clean up pet wastes. Runoff can carry wastes into lakes and streams. Either bury pet wastes or flush them down the toilet.

Drain hot tubs and swimming pools away from waterways and storm sewers. Chlorinated water is deadly to fish and aquatic life, and should be drained onto the ground or into domestic sewers.

Keep livestock away from streams and marshes. Animal wastes degrade water quality and their hooves can cause banks to collapse, leading to heavy siltation and possibly blocking the water flow.

Retention of natural vegetation along stream corridors is very important to stream habitat. Stream buffers are addressed in the Kitsap County Critical Areas Ordinance. Contact the Kitsap County Department of Community Development at 337-7181 to get buffer requirements before removing vegetation.

Keep litter out of the stream. This includes tree branches, grass clippings, old appliances or trash. Large objects can block the movement of water and fish and destroy fish eggs. Organic matter will rot and reduce the dissolved oxygen in the water. The oxygen is needed by fish and helps keep the water fresh smelling.

Don't alter natural waterways. Although well intentioned, any changes you make to your stream could destroy spawning beds and fish eggs or block fish migration. Do not build ponds and dams without proper guidance and approval from the Washington State Department of Fish and Wildlife.

Kitsap County Public Works
Surface and Storm Water Management Program
(360) 337-5777 or (800) 825-4940
openline@co.kitsap.wa.us