Failed roadside raingardens a lesson for the city

Seattle Public Utilities (SPU) is continuing its $500,000 project to remove some of the roadside raingardens and restore the planting strips to their original look.

One of the bulb-out raingardens that has been filled in with grass.

Earlier this week the Department of Planning and Development released SPU’s proposal to remove ten of the 13 bulb-outs. The proposal states that SPU will “restore the curb-line, roadway surfaces, and planting/parking strips to their former condition. The project also would install under-drains in some of the raingardens on 28th Avenue Northwest to eliminate surface ponding.” Information on how to appeal this plan or make comments can be found here. The project is expected to start late next month.

One of the failed roadside raingardens that has been filled in with dirt.

Mike Eagan with SPU tells us that while one-third of the raingardens failed, two-thirds are either working or will be working as soon as the retrofit is complete. “Although the results were not what SPU expected, it succeeded as a ‘pilot project’ in that it provided some important lessons, including the development (again, with community input) of designs that will help reduce Combined Sewer Overflows (CSOs) throughout the city,” Eagan says.

A look at one of the roadside raingardens from May

Ballard is a high priority for CSO reduction. “State and federal laws now require Seattle to reduce CSOs to no more than once a year per drainage basin,” says Eagan. “Ballard’s two drainage basins experienced 93 CSOs last year, dumping over 43 million gallons of combined stormwater and raw sewage into Salmon Bay.” Those numbers are about 25-percent or more of the city’s entire CSO volume in 2010, Eagan tells us. “For example, in December more than 23.5 million gallons overflowed into Salmon Bay. Even this past June, we saw six storm-related CSOs and four of those were in Ballard, spilling over half a million gallons of combined stormwater and raw sewage into Salmon Bay – 95% of Seattle’s total CSO volume for the month.”

City taking action on roadside raingarden concerns

The Ballard Roadside Raingardens pilot project has been a topic of conversation since they were installed last year. Whether you like them or not, it’s obvious that not all of them are working as designed – something Seattle Public Utilities is not taking lightly.

A look at one of the Ballard roadside raingardens

Back in February, the city met with neighbors of the raingardens to discuss what they are, why they’re there, how they’re supposed to work and to hear concerns. At that meeting, Seattle Public Utilities Deputy Director Nancy Ahern promised more communication. Since then, a Task Force comprising of members from the neighborhood and the city has been meeting.

A look at one of the Ballard roadside raingardens

Today, a letter from Ahern was sent to neighbors discussing many of the concerns that are being addressed by SPU. The goal is to “close the loop with the larger project community,” Ahern tells us on a recent phone call.

From the letter, the concerns include:

  • That several of the raingardens were not infiltrating as designed due to localized soil conditions
  • Concern about mosquito breeding from the non-draining raingardens
  • Objection to the signage placed on the “bump outs” to prevent vehicles from driving into the raingardens
  • Concern about safety hazards posed by 6 or more inches of standing water
  • Concern about the effect of the raingardens on property values
  • Concern about the side slopes of the raingardens and difficulty finding level footing when getting out of a car
  • Concern about inadequate information provided to the community, in the advance planning stages of the project, about the appearance of the proposed raingardens.

  • A look at one of the filled in roadside raingardens

    “Since this was a pilot project and the concerns stated above were unexpected outcomes, SPU agreed to remove raingardens that were not working and/or that met with serious objection,” Ahern writes. Of the 50 raingardens installed in Ballard nearly two-thirds are working correctly or will be retrofitted, the other one-third will be removed. Ahern tells us that the changes will cost the city about $500,000. “It’s dearly paid for, but will pay off in the future,” Ahern says.

    A look at one of the Ballard roadside raingardens

    “Our experience with this pilot has been immensely valuable, and we are already taking advantage of the lessons learned from this project in our ongoing work with green infrastructure,” writes Ahern in the letter to the community.

    As of right now, Ahern tells us they have no other roadside raingarden projects planned. “SPU is planning to take a year to gain experience from these designs before looking at possible roadside raingardens in other parts of Ballard or the rest of the city’s SCO basins,” she writes.

    Click here (.pdf) to read the entire letter.

    City responds to neighbors about raingardens

    Last week we wrote about a meeting held between residents who live along the Ballard Roadside Raingarden pilot project (map of project here) and Seattle Public Utilities.

    At the meeting, residents raised concerns about the ineffectiveness of the raingardens and the design standards. After the meeting, Deputy Director Nancy Ahren said the city would respond in a week. On Friday afternoon, this letter (.pdf) was sent to residents outlining a plan-of-action, which includes moving forward this week with retrofitting the raingardens that aren’t working.

    City to work with residents on Roadside Raingardens

    About six months after Seattle Public Utilities started the Roadside Raingarden Pilot Project in Ballard (.pdf map here), many residents who live next to them are upset. Nearly 75 people gathered to voice their anger, concerns and frustrations to members of Seattle Public Utilities at an emotional meeting Wednesday night.

    A properly draining raingarden.

    The problem, according to community members, is nearly half of the roadside raingardens don’t work properly. In the raingardens that don’t drain, inches of water will sit in the bottom for days after it stops raining. Andrew Lee the Combined Sewer Overflow manager for Seattle Public Utilities, acknowledges that there is a problem. “What we’ve seen is that some of these raingardens are not performing the way that the tests indicated they would,” Lee says. “They’re performing actually much worse.” The design standards call for the gardens to drain within 72 hours after the rain stops, a timeframe that some residents think is too long.

    Nearly half of the roadside raingardens aren’t draining properly.

    “We find ourselves in a difficult and surprising position with this project,” Nancy Ahern the Deputy Director of Seattle Public Utilities told residents. She says that Seattle Public Utilities has built successful raingardens in other parts of the city with happy citizens. That doesn’t seem to be the case in Ballard. “To be clear, we are very supportive of the raingardens,” Karrie Mathison said during a presentation by residents, “the point is we want them fixed.”

    Residents put together a presentation for SPU.

    During the two and a half hour meeting, many residents voiced their displeasure at many parts of the raingardens – the depth of them, the steep slopes, the standing water and the signage that the Seattle Department of Transportation requires. “We don’t believe that these are something that should be in our neighborhood,” one resident said, comparing the raingarden to a detention pond.

    One of the raingardens with a steep slope.

    A main theme throughout the meeting was the lack of communication between SPU and residents. “I would ask you, first of all, to be straight and honest with us as this develops and pay attention to the real needs of the community,” another resident told the contingent from SPU. That is exactly what SPU intends to do. “We are interested in partnering with the Ballard community,” Ahren tells us after the meeting. Within a week residents will get communication from SPU, Ahren says, and they will reach out to key leaders in the community to possibly create a task force. The plan is to work with the community to define what a successful raingarden is, she tells us.

    Signs required by SDOT for the “bump out” raingardens.

    The first course of action for SPU is to address the standing water. “Our first objective is to get the non-performing rain gardens to drain so we don’t have the standing water,” Lee told the group. “We fully understand the safety concerns that people have.” The department will do a retrofit to the non-performing raingardens as soon as possible to get them draining, although this may not be a final solution. Ahren wants the community to have a voice in what that final solution might be. If the raingardens that aren’t working can’t be fixed, SPU is willing to take them out and restore the street to the way it was, Ahren said at the meeting.

    The roadside raingardens is a pilot project for SPU to create a solution for Ballard’s Combined Sewer Overflow issues. If this first project is deemed successful, other parts of Ballard may get these raingardens. You can read more about the project here.

    Drainage issues in roadside raingardens

    To help reduce the amount of storm water that flows into the sewers, Seattle Public Utilities (SPU) is building roadside raingardens along 28th Ave NW.

    The future raingardens are still under construction and some of them are filling up with water during major storms like we had last weekend, and aren’t draining. “The swales have been filling up during the heavy rains and the water has been sitting in them for days without draining,” Nancy, one of the neighbors emailed us. “A few days ago there was a group of folks with clipboards and cameras having a meeting on the sidewalk and looking at the full swales.”

    “The drainage capability of the rain gardens will improve when the all of the weirs are installed and the landscaping is planted, mulched and growing,” Christine Woelfel, SPU Project Manager Supervisor tells us. “At present, some of the bio-engineered soil isn’t draining as anticipated and we’ll replace it before the plants and mulch go in.”

    Woelfel tells us that the inlets for many of the raingardens are plugged with sandbags to keep the water out during construction, and they’ve discovered that the seal isn’t tight enough. “All this rain is complicating the construction and we’ve needed to pump out the rain gardens to dry them out quickly so the contractor can get back to work as soon as possible to complete the project,” Woelfel says.

    “Additionally, the water depth in some of the unfinished rain gardens was deeper than 6-inches,” Woelfel says. “Since 28th Ave NW is a main path for school children, we wanted to be cautious and not allow deeper water, even on a temporary basis, so we pumped them out. Once the construction is done the raingardens will drain normally and pumping will be unnecessary.” (Thanks Nancy for the email and photo of the city pumping the raingarden.)

    Roadside raingardens to be installed soon

    Construction of the Roadside Raingardens project in Ballard is scheduled to begin in a few weeks. A total of 77 households will have gardens planted on the city-owned planting strip in front of their property, featuring a variety of plants and trees whose root structure is designed to hold stormwater long enough to absorb into the soil instead of pouring into combined sewer/stormwater pipes.

    An example of a roadside raingarden along Linden Ave N in Seattle

    Seattle Public Utilities employees were on hand during the final community planning meeting on May 12 to address any last concerns from residents affected by the project.

    “It’s a new approach to dealing with sewers,” said SPU project manager Karen York. She said the area has an average of 12 Combined Sewer Overflows per year, when the federal EPA requires an average of one. CSOs happen in older areas of Seattle where sewer and stormwater lines are combined, and during large storms they will sometimes overflow into Puget Sound to prevent sewer backups into people’s homes.

    Construction for the project is expected to get underway in mid-June. The project was originally slated to begin closer to April, due to the rigid timelines required in order to use the federal stimulus money funding the project. However, York said they were able to push back the date so residents wouldn’t be stuck with bare dirt for any longer than necessary before the plants went in this autumn. Half of the approximately $1.5 million in federal money is a grant that doesn’t need to be repaid, while the other half is a low-interest loan to the city.

    York presented a rough schedule of construction by area (map .pdf): 29th Avenue Northwest, 30th Avenue Northwest and 31st Avenue Northwest will be done between late June and August; 28th Avenue Northwest between 71st and 72nd streets during August; and 28th Avenue Northwest between 64th and 66th streets between August and October. Planting will begin sometime between mid-October and mid-November.

    York said this later planting would allow the plants to grow better than the earlier proposed schedule. Paul Brothers, the contractors for the project, will be responsible for monthly maintenance of all the gardens for three years after installation, at which point they will be maintained by SPU crews or another contractor hired by SPU.

    Shane DeWald, a Department of Transportation employee working with SPU, said they’re flexible on which plants are used, and have several combinations for residents to choose from for their own gardens, including Kelsey Dogwood, Barren Strawberry, Iris, and Swordfern. The deadline for plant selection is June 1, and any residents with a strong preference or allergy issues should contact York as soon as possible.

    Residents had a variety of concerns throughout the planning process. Don Sutherland, a retired city engineer, said he was skeptical gardens would actually have a significant impact on the CSO problem. “It might do something, but it’s not going to do the trick,” he said. He also worried that the clay-like soil in his area might absorb water so slowly that it might back up into the street.

    Claire Gibson, an SPU worker, said the planners have addressed whatever concerns they could. Areas with more clay-like soil will have a garden designed to accommodate that, she said. While the drains might back up during major storm events, as they sometimes do with the current system, Gibson said the gardens shouldn’t make that happen any more frequently.

    When residents told SPU they worried that letting stormwater go into the groundwater might flood yards and basements, SPU commissioned a monitoring survey. Six wells were dug around the affected area and had their water levels checked monthly since mid-October. The goal was to understand how high the groundwater actually got during the winter, in order to plan for how much water would be added to that.

    She said that all but two wells had no change in their water levels, and the wells that did change left plenty of space for the amount of water that would be retained, even at their peak.

    Shari Cantwell, another SPU worker, said they also listened to neighborhood feedback by reducing the size of the bump-outs in the curbs on 29th Avenue Northwest. The bumps are necessary in order to make the gardens big enough to catch enough rainwater to make a difference in the CSO problem. The sizes of the bumps vary depending on the size of the street.

    Neighbors have been concerned about the loss of parking as a result of those bumps throughout the project, and York said SPU conducted a study of cars parked in the affected areas in the evenings. She said she’s confident that there will still be enough room for everyone to park.

    Not all community members have felt heard, though. Mark, a homeowner who asked his last name not be given, said he’s felt the message from SPU has been, “You’re the target, we’ve got the money, this is what we’re doing, end of story.” Others simply don’t want the look of their neighborhood to change, as one neighbor said: “We just like the way things are now.”

    Liston-Riggs said she believes that when neighbors see the gardens, they’ll find they’re “an improvement, not an imposition.”

    York introduced key project members sure to become familiar faces to the 77 households getting raingardens: Scott Paul and Bill Kitchens of Paul Brothers, as well as Roslyn Liston-Riggs, SPU’s on-site engineer who will inspect the contractor’s work daily.

    In response to a question about garbage pickups during construction, Paul pledged that if any streets were so narrow that trucks couldn’t make it around construction, his company would bring cans to an accessible area to avoid service disruptions.

    Liston-Riggs has worked on several similar projects and said she’s ready to help with any issues or questions residents have as construction progresses. She said she understands some residents’ concerns about changes to the sidewalk area; it’s been something people are “used to having permission to use and enjoy.” This is the first time the city has asserted its ownership, which has been met with resistance on other projects as well, Liston-Riggs said.

    Another look at the raingarden along Linden Ave N in Seattle

    Once the gardens were finished, she said, all their concerns “melted away.” Liston-Riggs said she encourages anybody who wants a better idea of how the gardens will actually look visit the site on Linden Avenue North between 132nd and 143rd streets, which is the most similar project done so far.

    “It seems dramatic when it’s coming at you,” Gibson said, “but it seems to work out.”

    Residents can find more detailed construction information and regular progress updates by visiting and searching for Ballard Roadside Raingardens. Karen York can be contacted at or at (206) 386-9161.

    (Contributor Brionna Friedrich is a student in the University of Washington Department of Communication News Laboratory.)

    Roadside raingardens coming to Ballard

    In order to help reduce the amount of storm water that flows into the combined sewer system, Seattle Public Utilities will be constructing roadside raingardens along some Ballard streets.

    Example of a roadside raingarden.

    Starting next month, SPU will begin installation of raingardens in the public-right-of-way across ten blocks between NW 65th St and NW 85th St and 28th Ave NW and 31st Ave NW. Construction along parking strips, streets and alleys is not expected to take more than three weeks on each individual block. Planting in the raingardens will take place this fall and the entire project should be wrapped up by November.

    To learn more about the construction process and schedule, there is a meeting tonight at 6 p.m. at the Sunset Hill Community Club (3003 NW 66th St.) More information on the Roadside Raingarden project can be found here.

    Roadside raingarden meeting tonight

    Designs for the proposed roadside raingardens are almost complete.

    Seattle Public Utilities is holding a community meeting tonight to discuss the plans, which will affect an area of Ballard. The boundary for the project is 31st Ave NW to 29th Ave NW and NW 85th St to NW 75th St. Also 28th Ave NW between NW 65th St and NW 67th St (where NW 67th St enters from the east) and NW 70th St to NW 73rd St (where NW 73rd St enters from the west).

    At tonight’s meeting, Tracy Tackett with SPU will update the community about the plans, Claire Gibson will discuss groundwater monitoring and a representative from SDOT will discuss plant selection. After the speakers, the group will break up by block to give everyone the opportunity to ask questions and express concerns. Construction on the raingardens is expected to start April of next year. Tonight’s meeting is from 6:30 p.m. to 8 p.m. at the Sunset Hill Community Center (3003 NW 66th). Here is background on the project.