Tumwater City Hall and all City facilities will be closed to the public until further notice. Visit our COVID-19 webpage for more information.

Online City ServicesResources for Businesses | Resources for Residents Tumwater 2 Go

Police, fire, and emergency medical response services are available as usual. Emergency? Call 9-1-1.

Frequently Asked Questions about Stormwater

Press Enter to show all options, press Tab go to next option

FAQs about Stormwater

What is stormwater and why is it a problem?

Stormwater is water from rain or snow events. As rain and snow falls on the ground in natural areas, it is absorbed by the ground or slowly runs into creeks. In growing cities like Tumwater, there is less natural cover for water to soak in to; instead more of the water runs off. This excess water can cause nuisance flooding and possible threats to public health. In addition to flooding, stormwater can also be dangerous to human and aquatic health as it picks up pollutants such as gas, oil, and heavy metals off roadways and parking lots. 

What does stormwater runoff have to do with water quality?

Stormwater runoff picks up pollutants such as garbage, oil, gasoline, fertilizers, pesticides, pet waste, sediment, and anything else that can float, dissolve, or be swept along by the moving water. Left untreated, polluted stormwater can reach nearby streams where it can harm and even kill aquatic life. Polluted stormwater can all pollute groundwater, which the City of Tumwater uses as its drinking water source. A helpful rule of thumb is only rain down the storm drain!

What is an impervious surface?

An impervious surface is one where water cannot run through it and instead has to run off it. In natural areas, rain can hit the ground and infiltrate, but in urban areas, impervious surfaces don't allow water to infiltrate, creating large amounts of stormwater runoff. Rooftops, buildings, streets, parking lots, sidewalks, driveways, patios, and artificial turf are all examples of impervious surfaces. 

impervious vs pervious

What is a storm drain system and how does it work?

A storm drain carries stormwater away from streets, parking lots, and other hard surfaces. Storm drains are an important part of flood prevention as they  help maintain stormwater runoff by directing water off of streets and parking lots and into nearby streams. Keeping these storm drains clean and clear of debris can help to ensure they work properly during large rain events. 

catch basin

How much water passes through the storm drain system?

In urban areas with lots of impervious surfaces, surfaces that don't allow water to soak into them, the amount of water passing through the storm drain system fluctuates. In the drier summer months, watering and washing activities can produce hundreds of thousands of gallons of water that pass through the system and into local waterways. During wetter months, flows can increase to millions or even billions of gallons of water per day.

What kind of pollutants are found in the storm drain system?

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

Do storm drains get cleaned?

Yes! There are over 1,400 publicly-owned storm drains that are cleaned out at least twice a year with a vacuum truck. City staff uses vacuum trucks to sick debris out of storm drains before disposing of the waste properly.

Vac Truck

What happens if I see a neighbor, or someone else who's throwing trash into the storm drain?

Storm drains are in place to drain stormwater off of roadways and other impervious surfaces. Knowingly or unknowingly dumping trash, pollutants, and debris is illegal. Please report all illegal dumping to the 24-hour Spill Reporting Hotline by calling (360) 754-4150. For more information about reporting, visit the Spill Reporting page.

How can I properly dispose of used motor oil, antifreeze, old car batteries, or other potentially hazardous material?

Hazardous materials may be disposed of a HazoHouse in Lacey, WA. HazoHouse is a free service! Even so, please do your part to help reduce the amount of hazardous materials you use and buy.

For more information on reducing hazardous products, call HazoHouse at (360) 754-4111 or visit the Thurston County Waste and Recovery Center website.

HazoHouse generally accepts:

  • Auto products (used motor oil, filter, antifreeze, car batteries, or brake fluid). Used motor oil is also accepted at several auto-repair businesses throughout Thurston County.
  • Oil-based paints and latex paint manufactured before 1989
  • Thinners and solvents
  • Glues and adhesives
  • Batteries (excluding alkaline)
  • Solvents and cleaning supplies
  • Pool and hobby supplies
  • Fluorescent light tubes, yard light bulbs, and their ballasts and household compact fluorescent lights (CFLs)
  • Contaminated kerosene and gasoline
  • Propane tanks (no need to de-valve, 20lb/5 gal standard barbecue tanks only)
  • 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 double zip-lock plastic bags.HazoHouse logo

How are stormwater fees calculated?

Tumwater's stormwater service fee is based on the amount of impervious surface on each property and is developed using an Equivalent Residential Unity (ERU). Each ERU is equivalent to 3,250 square feet of impervious area. The charges to commercial, industrial, and other properties with large impervious areas will be substantially more than single-family residential properties because they create more runoff.

Who has to pay the stormwater service fee?

All developed property within the City of Tumwater 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 contributes to problems elsewhere in the City. This program recognizes that everyone contributes to the problem (runoff and pollution), and everyone will share in the results of the stormwater program (improved water quality, reduced flooding, unimpaired access to roads, etc.). Stormwater has public benefit of environmental stewardship and protecting our drinking water supply.

How are stormwater fees spent?

The stormwater fee pays for the City to maintain the roadways and its storm drains that 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 (CFPs) 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:

  • Improvements to stormwater quality through monitoring and reduction of illicit discharges and pollutants
  • Public information and education concerning stormwater issues
  • Increase 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