Pressure-Washing Work Near a Spokane Sidewalk or Storm Drain: Who to Ask
In the Spokane area, nothing but rainwater is allowed into a storm drain. That is not advice; it is the rule each stormwater programme here publishes, and inside the City of Spokane it is an ordinance. So before booking a house wash, a driveway clean or a concrete rinse, the question that settles whether the job is straightforward is not how the equipment is set up. It is where the water will end up, and whether anyone has asked the programme that owns that pipe.
This page is for the owner of a house they live in, arranging work on their own property. Two things change the answer, and both are labelled where they appear: which authority owns the ground — the City of Spokane, the City of Spokane Valley, or unincorporated Spokane County — and, inside the city, which kind of sewer the street in front of the house actually drains to.
Quick route
| Your situation | The authority to ask | Have ready |
|---|---|---|
| You do not yet know which jurisdiction covers the address | The jurisdiction lookup first, then that authority’s stormwater programme | Address and parcel number |
| The work will rinse siding, a driveway or concrete | The local stormwater or pretreatment programme, before the booking is confirmed | The street address, and where the water would run |
| Equipment, a hose line or a trailer will stand on the sidewalk or in the street | The street owner’s right-of-way desk, not the stormwater programme | Where it stands, and for how long |
| You have watched wash water, paint or concrete slurry go into a drain | The illicit-discharge line for that jurisdiction | Location, date and time, and what the material was |
| A spill is running right now | 911 first, then the programme | Nothing; call |
A storm drain and a sanitary sewer are not the same pipe
Across Spokane County and Spokane Valley the two systems are separate, and they end in different places. The county states that flows to the sanitary sewer — toilets, showers, sinks — are treated at the City of Spokane’s wastewater treatment facility and at the Spokane County Regional Water Reclamation Facility, while flows to the stormwater system run through storm drains, catch basins, drywells, grassed swales and infiltration ponds, seep “directly into the ground”, and may reach the Spokane Valley–Rathdrum Prairie aquifer, which the county calls “our sole source of drinking water in our region”.
The City of Spokane is a mixed picture, and its own stormwater page is the plainest account of it: more than 300 miles of separate storm sewers discharge stormwater to purpose-built treatment areas, to the Spokane River and to Latah Creek, while more than 400 miles of combined stormwater and wastewater sewers carry flow to the Riverside Park Water Reclamation Facility — combined sewers that sit predominantly on the city’s South Side. In heavy rain or fast snowmelt that combined flow exceeds what the plant can take, and the river receives an untreated overflow.
So the same rinse can recharge the region’s drinking-water aquifer in the county, or reach the Spokane River through a storm drain inside the city. Only the utility’s records settle which. That is why the first question is not “is this allowed?” but “which programme owns this pipe, and what does it require?”
What each authority prohibits, in its own words
City of Spokane. Municipal Code 17D.060.190 prohibits the introduction or discharge of anything into the municipal separate storm sewer system; it applies to activities on public or private property that may influence that system, and it requires owners and operators of private property to use and maintain best management practices so that illicit discharges do not occur. The City’s stormwater pages carry the same rule in one sentence: “Anything other than stormwater that goes into a storm drain is an illicit discharge.”
City of Spokane Valley. The City’s handout defines an illicit discharge as an unauthorised non-stormwater discharge leaked, drained, poured or spilled onto City property, rights of way or border easements that may reach stormwater facilities, and lists what its own staff have observed: petroleum products, automotive fluids, concrete wash-out, paint, sewer waste, trash, cooking grease, pet waste, and excessive dirt or gravel.
Unincorporated Spokane County. The county defines an illicit discharge as the disposal, release or flow of pollutants or non-stormwater materials into the stormwater drainage system. Its report list includes a pipe outlet running oily, frothy or discoloured, a fresh spill near a catch basin, and — the one that speaks to this page — “someone pouring or sweeping anything down a storm drain”.
The City’s own rules for washing work
The City of Spokane publishes a set of commercial wastewater best management practices for mobile washing operations. It is written for washing businesses, and it is the most specific local statement of what a Spokane washing job is supposed to look like. It tells the operator to:
- contact the local city or county for its discharge requirements and prohibitions;
- walk the area before starting, to find the nearby storm drains;
- dry sweep first, then wash;
- protect the storm drains with covers so wash water cannot enter the storm sewer;
- divert and collect the wash water, with strainers or filters, for disposal to the sewer through the building’s plumbing;
- use berms or sandbags to keep untreated runoff out of the gutter;
- put solids and debris in a bin, never down the sewer and never in the street, because clogs cause overflows;
- keep hazardous chemicals out of both drains, and treat oily waste as hazardous or run it through an oil-water separator;
- divert small amounts of wash water to landscape only after approval from the city or county;
- obtain the property owner’s permission before discharging wash water to the building’s sanitary plumbing; and
- carry a written spill response plan and clean-up materials on site.
The same sheet prints the programmes that answer the discharge question: the City of Spokane’s industrial pretreatment programme on 509.625.4600, Spokane County’s on 509.477.3604, and the City of Airway Heights on 509.939.7038.
Read that list as what the firm you hire should be able to answer; the household’s part is smaller and earlier — ask before the booking is confirmed. Yard debris falls under the same instinct: the City asks households to collect leaves and yard waste “so they don’t collect on the sidewalk or road and end up in storm drains”.
If the work needs the sidewalk, the gutter or the street
Part of a pressure-washing job is a public-way question rather than a discharge question. A hose line across the sidewalk, a trailer in the street, a washer staged in the parking lane: that is the ground of whoever owns the street, the alley or the sidewalk, and each of the three jurisdictions issues its own obstruction or right-of-way permit with its own notice period, fee and insurance terms. The exterior-service pillar records all three sets of rules, including the City’s printed obstruction fees. Wash water crossing that same sidewalk into the gutter is the discharge question above, and a small job is not exempt from it.
What to put to the firm before you book
| Question | What the answer tells you |
|---|---|
| Which programme did you contact about discharge at this address, and what did it require? | Whether the firm has done the step the City’s sheet names first |
| Where will the wash water go — collected, to the building’s sanitary plumbing, or to landscape? | Whether there is a destination at all, beyond the gutter |
| Who gives permission to discharge to the building’s sanitary plumbing? | The City puts that permission with the property owner, which is you |
| How will you keep the water out of the nearby storm drains? | Whether covers, berms or sandbags are part of the job |
| Will you dry sweep first, and where do the sweepings go? | How much loose material the water will meet, and whether it leaves in a bin rather than the sewer or the street |
| How are oily or hazardous materials handled if you find them? | Whether they leave as hazardous waste |
| Where will the equipment stand, and who holds the permit for it? | Whether the work has a right-of-way permission behind it |
| What is your spill plan, and what clean-up kit is on the vehicle? | Whether a small accident stays small |
Where this stops
- The programme decides, not this page and not the firm. A storm drain and a combined sewer cannot be told apart at the kerb: ask the utility rather than guessing, and do not open, clear or pour anything into a catch basin.
- Nothing here is a method. No pressure setting, no cleaning product and no surface advice appears on this page; those are the job’s own subject and belong to whoever does the work.
- Something oily, frothy or discoloured leaving a pipe, or anything being poured or swept into a drain, is worth a report: City of Spokane 509.625.7999, Spokane County’s Storm Drain Dan hotline 509.477.7525, Spokane Valley 509.720.5000. Give the location, the date and time, and what the material was.
- A spill is not a report. For a hazardous spill or any other emergency, call 911, and report a spill to the sewer immediately to the City’s pretreatment programme.
Next step
One action, before the booking is confirmed: ask the firm which programme it contacted for your address, and what that programme said it required. A vague answer is itself an answer. Settle the jurisdiction first — the jurisdiction guide and the project resource router carry the lookup and the office behind it.
Report an error or a change you have spotted: use our contact page.