Soaking It Up in Puyallup

Puyallup, once a fertile farm town and now a suburb of Tacoma, is likely not the first Northwest city that’s brought to mind when you think of progressive, green-focused innovation. But in the area of stormwater solutions, Puyallup is just that.

Since August 2009, the city has helped residents install 20 rain gardens in three different neighborhoods. Now it’s lining up funding for even bolder improvements, including paving alleys with porous asphalt and rebuilding an entire residential block to soak up and treat most of the stormwater that hits the road.

The prime objective of the stormwater improvements is to help cleanup and protect Clarks Creek, a spring-fed stream that flows through the city, feeding into the Puyallup River. The creek is home to five kinds of salmon, but is plagued by pollution, high levels of fecal coliform bacteria and low levels of oxygen, and is choked in places by weedy plants.

Polluted stormwater is fouling the creek and countless other water ways throughout the Northwest, including surfacing as the top threat to the health of Puget Sound. The filthy water that gushes off roofs, highways, and parking lots carries with it surprising volumes of oil and grease, heavy metals, pesticides and other toxic chemicals. The torrents of water erode stream banks, flood homes and roadways, and wash away salmon eggs and insects.

Portland is the Northwest’s leader in smart stormwater solutions with its Grey to Green program, with Seattle in strong contention with its SEAStreets and other efforts. Now Puyallup’s green infrastructure projects are helping cleanup and reduce stormwater volumes, as well as having other, less expected benefits as well.

“I’ve been seeing neighborhoods coalesce (around the projects),” said Mark Palmer, a stormwater engineer for the city and lead on the effort. “They become a close knit little community.”

All of the rain gardens are installed at once in a neighborhood. Palmer has helped organize community events around the installations, creating mini environmental fairs whose guests have included gardening guru Ciscoe Morris. In each neighborhood are two prominent informational signs that describe the projects and how they work to anyone passing by.

Taking the rain garden pledge

Part of the new-found cohesion could come from an interesting feature of these rain gardens: All of the residents who get one have to sign an agreement to maintain the garden as stormwater infrastructure. Their property adopts a covenant that passes along to future owners.

“That’s important to have that link,” Palmer said.

It’s a smart strategy considering that the rain gardens represent a public investment of approximately $2,000 to $3,800 per site. The funding for the three Puyallup projects has come mostly from Washington Department of Ecology’s Pass Through Grants, as well as the Green Partnership Fund (which comes from the Pierce Conservation District and the Tacoma Community Foundation), plus volunteer labor and donations from local businesses.

Rain gardens are super absorbent, shallow depressions planted with vegetation that’s tolerant to extremely wet conditions at their bottom. In Puyallup, the rain gardens are linked by buried pipes to roof downspouts. So instead of sending the runoff that comes gushing off of roofs straight into the stormwater system or onto roadways and parking spots, the water flows into the garden where it soaks into the ground slowly and pollutants are filtered out.

Maintenance of the rain gardens involves weeding and pruning and occasionally adding more mulch to the landscape.

The neighbors on 8^th Avenue Northwest have been particularly enthusiastic rain gardeners. On a recent visit to the street by Palmer, resident Steve West immediately starts grilling him about the possibility of expanding the green infrastructure in his ‘hood. And his existing rain garden, which was installed in fall 2009?

“It’s fabulous,” West said.

But now, the road in front of West’s house is pocked with puddles and the asphalt is crumbling at the edges. Conventional stormwater infrastructure—pipes and gutters and retention ponds—are limited in this neighborhood near downtown.

Follow the porous asphalt road

Puyallup is exploring the idea of ripping up West’s whole street and installing porous asphalt and lining the street with rain gardens. The city has set aside more than $100,000 for the project and is talking with Ecology about getting an additional $300,000. The vision is to make it a model of what’s called low-impact development, or LID.

Also in the works are plans for paving the gravel alley behind West’s house with porous asphalt. Right now, the alley puddles so badly that West has built a small levee to keep his backyard from flooding. Every year the city regrades all seven miles of gravel alleys; installation of porous asphalt would put an end to that practice and save money. Palmer hopes to do more alleys than just those on 8th.

The challenge to shrinking the Northwest’s stormwater woes is expanding the use of green solutions—rain gardens, porous pavement, planted green roofs, and most importantly saving native plants and trees—fast enough and widely enough to make a dent in the problem. The biggest hurdle in Puyallup and elsewhere is getting people to preserve trees that catch rain drops in their branches and allow them to evaporate, and that suck rain water out of the ground. (Seattle and Portland are working on tree preservation regulations, but the best bet for conservation is setting urban growth areas that protect undeveloped land in rural areas.)

The engineering strategies for dealing with polluted runoff can’t solve the problem without the conservation of significant amounts of vegetation. After all, the ground can absorb only so much water.

Palmer knows the battle is uphill, but will keep working to educate people about smart stormwater projects and install fixes where he can. There are plans for rain gardens in three more neighborhoods, plus a rain garden class and tree plantings in riparian areas along creeks.  It’s going t
o take time.

“We’re talking about reversing a couple 100 years of development,” he said.

Summary of Puyallup’s stormwater projects:

8th Avenue Northwest:

• 7 rain gardens
• Installed August 2009
• $22,000 in-kind and actual costs from the Green Partnership Fund (Pierce Conservation District and Tacoma Community Foundation)
• Plans being worked on to install porous asphalt in neighboring alleys, and for a SEAStreets type project in which an entire block’s roadway is made porous and rain gardens are installed

5th Avenue Southeast:

• 7 rain gardens
• Installed June 2010
• $15,891 from Ecology’s Pass Through Grant, plus in-kind donations

18th Street Southwest:

• 6 rain gardens, 1 porous-paver driveway covering 1,200 square feet
• Installed September 2010
• $24,414 from Ecology’s Pass Through Grant, plus $750 from local businesses and in-kind donations

All photos from Lisa Stiffler and feature Puyallup stormwater projects.