Should You Disconnect Your Downspouts in Multnomah County?

Here’s What Multnomah County and Portland Homeowners Need to Know

If you’ve lived in Portland or Multnomah County for a while, you may remember a time when the city offered incentives to homeowners who disconnected their downspouts from the sewer system. The goal was simple: reduce the volume of stormwater entering the combined sewer system to help protect local rivers from overflows during heavy rains.

But what about today? Do they still want you to disconnect? Are there any discounts available? Let’s clear up the confusion.

The Program Still Exists (But Looks a Bit Different Now)

While the City of Portland no longer offers the one-time payments for disconnecting your downspouts, the spirit of the program is alive and well. Portland still wants you to disconnect your downspouts—because it helps reduce the risk of sewer overflows during heavy rains.

Instead of a one-time incentive, the City now offers ongoing discounts through the Clean River Rewards program. If you manage your stormwater on-site—meaning your rainwater doesn’t go into the city’s sewer system—you can qualify for a lower monthly stormwater charge on your utility bill.

Why Disconnecting Matters

The City of Portland has a “combined sewer system” in many neighborhoods. This means both rainwater and household wastewater travel through the same pipes. During heavy storms, this system can get overwhelmed and overflow into the Willamette River. Disconnecting downspouts helps reduce that burden by diverting clean rainwater into your yard instead.

How to Disconnect Properly

The City wants you to do it safely and correctly. Here’s what they recommend:

Direct water away from your house: Make sure the ground slopes away from your foundation.
Keep your distance: Downspout extensions should be at least 6 feet from basements and 2 feet from crawl spaces or slab foundations.
Respect property lines: Aim for at least 5 feet away from the edge of your property—especially if your yard slopes toward a neighbor’s.
Use the right materials: Elbows, extensions, splash blocks, and maybe even rain gardens can all help direct and absorb water effectively.

If you’re unsure how to do it, the City offers a free guide: How to Manage Stormwater with Downspout Disconnection (PDF).

Stormwater Discounts Are Still Available

Even though the original cash payment is gone, the Clean River Rewards program can still save you money each month. If you’re managing your rainwater responsibly—through rain gardens, drywells, rain barrels, or simply redirecting water into your yard—you could qualify for a discount on your water bill.

Want to know how much you might save? Try the Residential Discount Calculator.

What About Unincorporated Multnomah County?

If you live outside Portland city limits but still in Multnomah County, the situation is a little different. The county doesn’t offer any direct discounts for downspout disconnection, but it does require that any new or replaced impervious surfaces over 500 square feet have a drainage plan that manages stormwater on-site. So, while you won’t get a discount, you’re still expected to keep runoff out of the public system.

The Bottom Line

✅ Yes, Multnomah County and the City of Portland still encourage you to disconnect your downspouts.
✅ No, the old financial incentive program is no longer available—but ongoing discounts exist.
✅ Yes, you should make sure your disconnection is done safely and within guidelines.

If you’re not sure whether your home qualifies or how to make changes, it’s worth reaching out to the City of Portland’s Bureau of Environmental Services or Multnomah County Land Use Planning for more info.

Got questions or experiences with disconnecting your own downspouts? Share your thoughts in the comments below—or get in touch if you need help figuring it all out!

Lloyd Anderson