Stormwater FAQ

Stormwater Frequently Asked Questions

What is stormwater and why is it a problem?
What is impervious surface?
How is the stormwater service fee calculated?
Who has to pay?
Why should I have to pay? I live on a hill and have no drainage problem.
What is the money be spent on?
What is a storm drainage easement?
What is a catch basin?
Are sewers and storm drains the same thing?
Do catch basins and storm drains get cleaned out?
What kinds of pollutants are found in the storm drain system?
Can filters or screens be installed in front of catch basins?
How much water passes through the storm drain system?
I see people dumping their used oil into storm drains all the time. What can I do?
What happens if I see a neighbor, or know someone who's throwing trash into a storm drain?
How can I properly dispose of used motor oil, antifreeze and old car batteries?

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What is stormwater and why is it a problem?
Stormwater is water from rain and snowmelt. As rain and snow falls to earth in agricultural and undeveloped areas, it is either absorbed or it slowly runs off and dissipates. In a growing city like Tumwater, where rooftops and paved areas not only prevent the water from being absorbed, but also help it run off at a much faster rate, problems arise. Unmitigated, the stormwater could accumulate in many areas of the city, causing nuisance flooding and possible threats to public health and safety. Flooding is only a part of the problem. As the rain falls onto our streets and runs off, it carries with it pollutants such as gasoline, oil, and heavy metals. Pesticides, herbicides, and fertilizers are washed from lawns and other green spaces. With the passage of time, these pollutants will buildup in our waterways and underground drainage systems causing significant environmental damage to our streams, rivers and lakes. These pollutants may also threaten our drinking water supply.

What is impervious surface?
Impervious surface means those disturbed or hard surfaced areas that either prevent or retard the natural entry of water into the soil. Rooftops, buildings, streets, parking lots, sidewalks, asphalt, concrete, other paving, driveways, gravel, patios, artificial turf and storage areas are all examples of impervious surfaces. These improvements effect natural infiltration, creates more runoff, increases the rate of runoff and alters runoff patterns of stormwater that drains from an area.

How is the stormwater service fee calculated?
Tumwater’s stormwater service fee is based on the amount of impervious area on each property and is developed using an Equivalent Residential Unit (ERU). Each ERU is equivalent to 3,250 square feet of impervious area and is billed $5.70 per month. The charges to commercial, industrial, and other properties with large impervious areas will be substantially more than single-family residential properties because they create much more runoff.

Who has to pay?
All developed property within the City of Radcliff will pay the stormwater service fee. That includes houses, schools, public facilities, churches and businesses. The only exceptions are streets within the City. These areas are excluded because they are designed to collect and carry stormwater runoff.

Why should I have to pay? I live on a hill and have no drainage problem.
You may not have a problem, but the runoff generated from your property is contributing to problems downstream. The approach being taken through this program recognizes that everyone contributes to the problem (runoff and pollution) and everyone will share in the results (improved water quality, reduced flooding, unimpaired access to roads, etc.).

What is the money be spent on?
The stormwater fee pays for the City to maintain the roadways we all use to help prevent flooding and impacts to homes and businesses from stormwater. Funds are also allocated to various programs, such as Stream Team, to help reduce the impacts of pollutant-laden stormwater on our rivers and streams through education, outreach, and community involvement. The City also engages in numerous Capital Facilities Projects to enhance treatment and reduce the quantity of stormwater coming off our roadways and discharging into rivers and streams. Some of the other important components of the stormwater program include:

Improve stormwater quality through monitoring and reduction of illicit discharges and pollutants
Public information and education concerning stormwater issues
Increased maintenance/repair of the City's stormwater system
Development of stormwater design standards and regulations
Field inspection/enforcement of these standards
Construction of stormwater projects.

What is a storm drainage easement?
A storm drainage easement is a legal document, which allows for both access during construction and future maintenance. Granting an easement to the City does not reduce the size of one's property, but it does create some limitations within the easement area.

What is a catch basin?
A catch basin is a curbside receptacle whose function is to convey water from streets and other urban surfaces into the storm drain system. The design of this drainage structure includes a sump that captures and temporarily stores some pollutants such as oils and sediment. Regular maintenance to clean out the sump removes the stored pollutants and prevents them from washing further into the storm drain system and into receiving waters such as the Deschutes River.

Are sewers and storm drains the same thing?
No. They are two completely separate systems. The sewer system, also known as the sanitary sewer or wastewater sewage system, conveys household, commercial and industrial wastewater through a separate plumbing system into an underground sewer pipe system. Wastewater in the sanitary sewer system is from sources such as water and waste from sinks, toilets, washers, and car washes, to name but a few. Discharges to the sanitary sewer system receive extensive treatment and filtration at the LOTT wastewater treatment plant prior to being discharged into Puget Sound. The storm drain system on the other hand, after treatment, discharges directly into the Deschutes River, Percival Creek, infiltrates into the ground, or other body of surface water.

Do catch basins and storm drains get cleaned out?
Yes. There are over 1,400 publicly owned catch basins that are cleaned at least twice a year with vacuum trucks. Problematic locations throughout the area where certain catch basins, because of either location or repeated illegal dumping are cleaned more frequently. Open ditches and detention basins are also part of the areas storm drain system. These facilities are routinely checked and cleaned of weeds, trash, and debris at least once a year.

What kinds of pollutants are found in the storm drain system?
Paint thinner and paint products, used motor oil and antifreeze, pesticides and fertilizers, sediments containing heavy metals, Styrofoam cups and paper trash, human and animal feces, golf balls, dirty diapers, and dead animals are but a few of the many pollutants found in the system on a regular basis.

Can filters or screens be installed in front of catch basins?
It sounds like a good idea. But during a rainstorm, leaves and trash in the streets are quickly swept into catch basins. Filters or screens installed in front of catch basins could cause leaves and trash to accumulate and clog the grate, preventing proper drainage and causing flooding hazards. Temporary filters or screens are sometimes placed in front of catch basins located near construction sites. These structures are also known as best management practices (BMPs) and are required to prevent sediment and construction site wastes from entering the storm drain system. Ponding will occur at protected catch basins causing possible short-term flooding. There are new technologies being developed in the form of filtration or screening devices that can be installed and inserted inside catch basins.

How much water passes through the storm drain system?
In urban areas where much of the natural surface has been replaced by pavement and buildings, the majority of the water from storms runs off these hard surfaces and flows into and through the storm drain system. In addition, dry weather flows from individuals washing their cars, draining their pools and over-watering their lawns, to name but a few activities, also flows into the storm drain system. On a typical dry summer day, watering and washing activities can produce hundreds of thousands of gallons of water draining into the system and eventually into the Deschutes River. During a heavy rainstorm, this flow can increase to millions or even billions of gallons.

I see people dumping their used oil into storm drains all the time. What can I do?
Dumping used oil into storm drains is illegal. One gallon of motor oil can ruin a million gallons of fresh water - a year's supply of water for 50 people. To report illegal dumping in Tumwater call (360) 754-4140, or contact Thurston County Environmental Health Services at (360) 754-4111. To properly dispose of your used, but uncontaminated (mixed with other fluids) motor oil, dispose of it at HazoHouse, located next to the recycle blue boxes at the Thurston County Waste and Recovery Center, so you can drop off unwanted household hazardous materials before you weigh in at the toll booth. The Thurston County Waste and Recovery Center is located at 2418 Hogum Bay Road N.E. in Lacey. From I-5, take Exit 111, head north on Marvin Road, and turn east into the facility entrance.

What happens if I see a neighbor, or know someone who's throwing trash into a storm drain?
Storm drains are for the sole purpose of draining rainwater. Knowingly or unknowingly dumping trash, pollutants and debris into catch basins is illegal. If it's a neighbor, they may not understand the catch basin's direct connection to the areas surface waters. If you have an amicable relationship with him/her, it may be just a matter of informing and making them aware of its environmental impact. If this doesn't work, call (360) 754-4140, or contact Thurston County Environmental Health at (360) 754-4111.

How can I properly dispose of used motor oil, antifreeze and old car batteries?
Hazardous materials may be disposed of at HazoHouse in Lacey. HazoHouse is a free service, however, it still costs a lot of money to dispose of these items. Please do your part by reducing the amount of hazardous products you use. This will help protect your health and the environment too. For more information on reducing household hazardous products, call (360) 754-4111 or route an e-mail message through wwm-webmaster@co.thurston.wa.us. You can also order free publications on-line by clicking here. HazoHouse also accepts:

Auto products (used motor oil, filters, antifreeze, car batteries, brake fluid)
Certain paints (see guide)
Thinners and solvents
Pesticides
Glues and adhesives
All types of batteries (includes all alkaline, rechargeable and lead-acid batteries)
(also visit the Rechargeable Battery Recycling Corporation for a list of local sites that accept rechargeable batteries)
Solvents and cleaning supplies
Pool and hobby chemicals
Fluorescent light tubes, yard light bulbs and their ballasts (please bring no more than 30 tubes or bulbs per trip)
Contaminated kerosene and gasoline
Propane tanks (no need to de-valve), 20lb/5 gallon standard barbecue tanks only.
Used motor oil (please bring to the self-serve station near entry to HazoHouse). Used motor oil is also accepted at several auto-repair businesses throughout Thurston County. Click here for more information.
Products containing mercury (Do not break fluorescent bulbs; transport them in their original boxes if possible. Place thermometers in their original containers, too, or in two zip-lock plastic bags.) Click here for more information about mercury.

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