Each year, tens of millions of gallons of untreated water from combined sewer overflow (CSO) gushes into Salmon Bay. In 2011, the number totaled 43,700,000 gallons of water, according to a report from the Washington State Department of Ecology.

By comparison, an Olympics-sized swimming pool carries 600,000 gallons of water. It would take about 72 of them to fill all of the polluted storm water Ballard has contributed to the Puget Sound in the year 2011 alone.

Between NW 65th St and NW 80th St, residents sit on top of combined sewers, meaning that sewage and rain water go to the same place. The sewage and rain water travel through pipes down to the West Point Sewage Treatment Plant in Magnolia, otherwise known as the Ballard Siphon. But when a storm event occurs and the combined sewer overflows, the result is that the sewage spills out into Salmon Bay at different points along the way.

During the winter months, CSO occurrences happen regularly. In 2011, 72 occurences happened overall. Not that it takes much to happen -- overflows can happen after as little as one-tenth of an inch of rain has fallen, according to SPU.

In the city, rain has nowhere to go but down. Since roofs, sidewalks and streets have no absorbtion capabilities, and what yards, grass and soil there is becomes quickly saturated, rain water will go down pipes or down hillsides and eventually into the Puget Sound. Storm water, in addition to sewage from CSO, can carry with it any oil, pesticides, fecal matter and other contaminants that it passes through.

For one long-time Ballard resident, Liz Tennant, the problem is appalling. In fact, it led her to co-found a neighborhood group called the Ballard Rainwater Consortium, which is dedicated to informing residents about CSO pollution and finding the right solution to fixing it.

“We really get that Puget Sound is at risk and we really want to collaborate with all the people and stakeholders to figure out what makes the most sense,” she said.

The group may get their chance, as Seattle Public Utilities is ramping up to engage in projects which would reduce CSO, primarily through roadside rain gardens and, in the longer term, a large underground container to store storm water.

The former plan may cause some concern for Ballardites, who may still feel the sting from last time SPU tried to swing in to save the area from CSO.

In a pilot project last year, called the Ballard Natural Drainage Project, SPU installed 10 blocks-worth of rain gardens throughout Ballard. It turned into a mess. The rain gardens did not properly absorb water and soon roads were flooding with water. Despite complaints and photographic evidence from residents, SPU did not respond in a timely or courteous manner. One-third of the rain gardens ended up being ripped out and another third needed fixing, costing an additional $500,000.

Despite a bad first round, Andrew Lee, the CSO manager for SPU, said that they have learned their lesson and are ready to try again.

At the Ballard District Council meeting on September 12, Lee was apologetic and realistic about the mistakes which happened during last year’s debacle.

“We rushed the project. We did it too fast,” he said. “(We) didn’t leave enough time for community input.”

He said that SPU tried to fit the project into a nine-month time span in order to take advantage of federal funding. He said they did not adequately test the soil and ignored warning signs (i.e., community complaint, pits not absorbing water when first dug). Moreover, they never bothered to gather community input during the design phase, picking out sites before acknowledging any opinions and brazenly pushing the project through.

With lessons learned from these mistakes, Lee said they can get it right this time.

“My response is, ‘Failure is if we make the same mistakes again,’ “ he said. “This is why I am here talking about doing a similar project, but incorporate the lessons we learned.”

This time, SPU has yet to pick out the sites and will be conducting community meetings. In addition, the design phase will take a considerable more amount of time, with construction on the rain gardens not beginning until 2015, Lee said.

Community cooperation is essential, he said.

“It is paramount to us that we build projects that people are not going to be upset about, and that indeed will be of value to the neighborhood,” he said.

Laura Cooper, a community resident who lived on one of the blocks which flooded last year, was hopeful that SPU could do it right this time.

Tennant, while she said she appreciates SPU’s efforts to involve the community more, wants to be cautious.

“I’m hoping they’ll be viewing this as an exploration and not a foregone conclusion,” she said. “They should go through the steps before they determine to do this.”

In the meantime, Tennant, Lee and other proponents of reducing rain water are encouraging residents to take their own initiative.

Through the SPU RainWise program, Ballardites can get rebates for technology that will help divert storm water. This includes rain gardens that can be planted on private property (the soil must be tested first) or the installation of cisterns.

Overlooking the Puget Sound from Sunset Hill Park, with the sun reflecting off the water and the Olympic Mountains visible in the distance, Tennant gave an almost inaudible sigh.

“This is really one of my inspirations for what I do,” she said. “Because I love Puget Sound and Salmon Bay.”