SPU test soil for roadside rain gardens in Ballard

Seattle Public Utilities (SPU) are currently in the process of testing soil in areas of Ballard that have been identified as most suitable for roadside rain gardens. After feedback from the Open House event in February, from the results of a community survey and after a briefing with Ballard Stormwater Consortium in March SPU decided to move forward with plans to embark on the test digs.

As we reported in our post in February, through the creation of rain gardens, SPU aims to minimize street runoff flowing into Salmon Bay. According to SPU, last year 89 sewage overflows sent 57 million gallons of raw sewage and polluted stormwater into the bay. SPU issued a letter to the community to inform locals about the rain garden project.

The test digs are being implemented as Phase Two of SPU’s plan. Large holes, about 4 feet deep, can be found in the test dig areas between the blocks of NW 65th St and NW 85th St and 15th Ave NW and 32nd Ave NW. Ballard Stormwater Consortium received an original map and schedule from SPU, however, after initial vactor tests three of the selected sites were found to have unsuitable soil for infiltration. SPU then selected alternate sites and worked with SDOT to revise their street use permit. Check out the draft revised map of the testing sites that Ballard Stormwater Consortium received on April 5.

Vactor tests were carried out last week at 2354 NW 73rd St, 7359  23rd Ave NW, 2101 NW 77th St and 7057 22nd Ave NW. Further testing was carried out Monday, April 8, and tests are also scheduled to take place today.

Ballard residents have expressed both short and long term concerns about the aesthetic and hygienic repercussions of having huge holes in front of their houses. In response to long term concerns, SPU have confirmed that they will be monitoring and replacing the top soil once the rain gardens are eventually set up approximately every 15 years.It is important to note that these roadside rain gardens are set to be hugely different from the controversial rain gardens removed by SPU in 2011.

My Ballard reader Marieka emailed in to let us know that tests were being done outside her house on 19th Ave NW. “I LOVE the successful rain gardens in the parking strip on 30th Ave NW. I’m really worried that only people who are against it (and often against any change) are being heard from,” wrote Marieka.

The roadside rain garden that Marieka is referring to on 30th Ave NW will be used as an example for SPU to look to when constructing new rain gardens when the sites are confirmed. Currently SPU have a timeline of implementing roadside rain gardens to assist in the overflow problem by 2015.

Further community meetings are planned for May to report the results of the test digs and to discuss the next steps that need to be taken in the project.

Do you have a test dig site in front of your home? Email us at tips@myballard.com and tell us what you think about the roadside rain garden project.

We will update readers on the test dig results and the schedule of future community meetings when more information in known.

Check out the photo above of a roadside rain garden in Ballard. Photo courtesy of Seattle Public Utilities.