Where a Dog Daycare's Turf Run Drains: Storm Drain, Sanitary Sewer, or the Utility's Call

Settle the drain before the base goes in

A dog daycare’s turf run isn’t just a surface decision. Every wash-down, every rinse, every rain shower that lands on it has to go somewhere, and where it’s allowed to go is a question for your storm drain authority and your sewer utility, not for the drainage sketch alone. Get both answers in writing before the layout is finalized, because moving a drain line after the base is built costs more than asking first.

The two paths aren’t interchangeable defaults. The storm drain system carries rain to a creek or river with no treatment in between, so most jurisdictions bar wash water from reaching it. The sanitary sewer carries flow to a treatment plant, but most sewer utilities bar stormwater from entering that system, because their plants aren’t sized to treat rain. An outdoor dog run generates both wash water and, if it’s uncovered, stormwater. That’s why the drainage question doesn’t resolve itself.

What the storm drain rule requires

Storm drain ordinances nationwide are commonly built from a shared template: EPA’s Model Illicit Discharge and Connection Ordinance, posted December 2015. It’s a model for local governments to adopt, not a law that applies on its own — so the version your city or county actually passed is the one that governs, and it may differ from the template. Still, the model shows how these ordinances are typically built, and most local versions follow its shape closely.

The model’s Section 2 defines an illicit connection as any drain or conveyance that lets a non-storm water discharge — including “sewage, process wastewater, and wash water” — enter the storm drain system. Its list of pollutants that trigger the prohibition names “animal wastes” specifically. Section 7 sets out the exemptions: things like landscape irrigation, air conditioning condensation, and “non-commercial washing of vehicles” are allowed to reach the storm drain. Commercial washdown of a dog run isn’t named as an exemption anywhere on that list.

Read plainly, that means a dog daycare’s turf run washdown is the kind of discharge these ordinances are written to catch, not the kind they carve out. Before the drainage plan is set, pull your own city or county’s adopted illicit-discharge ordinance and confirm how it defines and exempts wash water — the local text, not the EPA template, decides your case.

What the sanitary sewer side requires

Routing washdown to the sanitary sewer instead sounds like the fix, but sewer utilities have their own prohibition working in the other direction. Metro Water Recovery’s Rules and Regulations, effective 1 July 2018 and revised through July 2018, bar “stormwater, directly or indirectly, from surface drains, ditches, or streams, storm or combined sewers, roof, or from any other means” from entering the sanitary system — unless it’s authorized under the service contract or under the district’s own memorandum on “outdoor facilities with incidental and insignificant amount of stormwater,” dated 7 January 2015.

That’s the catch for an uncovered turf run: it collects rain along with rinse water, so a straight tie-in to the sanitary sewer can put stormwater into a system that’s built to exclude it. Whether your washdown qualifies under an incidental-stormwater exception — like the one Metro Water Recovery has on file — is a question only the utility serving your address can answer, and it depends on how the run is built, not just what it’s used for. A different utility may have a different rule, a different exception, or none at all. Ask before the drain line is run, in writing, and keep the answer with the project file.

What a professional install plans around

This is exactly the kind of site condition a proposal should account for before pricing, not discover during construction. On the free visit we measure the run and check the ground, and a facility with an outdoor washdown area needs the drainage question answered before we finalize a layout you approve. The base we build is matched to your soil either way, but where the water goes after it leaves the surface is a separate decision from how the base drains water down through it — our article on why turf can smell like dog urine covers what happens when drainage and cleaning routine don’t match the use.

An uncovered run puts three design options on the table, and which one fits depends on the utility’s answer:

• A roof or covered structure over the run, which keeps rain out of the wash water entirely and simplifies which system the washdown belongs to.
• A curb, berm, or diverter that routes rain around the drain while the washdown still reaches its intended outlet.
• A separate stormwater line, kept apart from the washdown line, so each flow reaches the system built to handle it.

None of those is a default answer — they’re options to bring to the utility conversation, not a substitute for it. Our kennel and dog daycare guide covers the surface and layout side of a commercial run; this article is about the one decision that sits outside the surface choice entirely.

Questions to settle before the project is final

Before the drainage plan and drain tie-in are fixed, get written answers to:

1. What does our own city or county’s illicit-discharge ordinance say about wash water, and does it name or exempt commercial washdown?
2. What does our sanitary sewer utility’s rule say about stormwater entering its system, and is there an incidental-stormwater exception we might qualify for?
3. Is the run going to be covered, curbed, or piped separately, and does that choice change which system the washdown belongs to?
4. Which department actually issues the answer — a stormwater office, a sewer utility, or both — and do we have their answer in writing?
5. Does the plan change if the run expands later, adding more square footage or more dogs than the utility’s original answer assumed?

A daycare’s rinsing routine also matters for how the turf itself holds up day to day; see our pet turf cleaning guide and, if your area sees watering restrictions, rinsing pet turf during those restrictions for the maintenance side once the drain question is settled.

A short checklist before you order turf

• Get your local storm drain ordinance’s wash-water definition and exemption list, in writing.
• Get your sanitary sewer utility’s stormwater prohibition and any incidental-stormwater exception, in writing.
• Decide whether the run will be covered, curbed, or piped separately, based on those answers.
• Bring both answers to the free visit, where we measure the run, check the ground, and build the layout you approve around the drainage plan that’s already settled — not one guessed at afterward.

Call 303-349-2368 to schedule the visit once you have the utility’s answer, or before, if you’d rather work through the layout questions together first.