PORT ANGELES — The city has secured a $150,000 grant from the state for water quality filtering units that will take fecal coliform bacteria and other contamination out of stormwater discharging into Peabody Creek.
The project will be the first of its kind in Port Angeles to install water-filtering structures to improve the health of a specific creek.
Once completed in 2015, the project could pave the way for future efforts targeting other creeks in Port Angeles, city stormwater engineer Jonathan Boehme said.
“What kind of success we would see would help us determine if this is the exact project we want to start installing everywhere,” he said.
Water sampling data gathered between 1999 and 2011 found Peabody Creek had the highest level of fecal coliform bacteria of the five creeks within the city limit, Boehme explained.
Tumwater Creek came in with the second highest percentage of samples above state standards, with Dry Creek, Valley Creek and Ennis/White Creek following in order.
Boehme said the bacteria likely comes from a variety of locations, such as dog feces left along city streets or in parks, rather than a few specific spots.
Filtering units
Between six and eight stormwater-filtering units will be placed under sidewalks along Francis and Albert streets.
Stormwater pipes will direct water through the units before the flow gets to an outfall in a culvert through which Peabody Creek flows under Peabody Street.
City Council members unanimously voted to accept a $150,000 grant from the state Department of Ecology for the project at their April 15 meeting.
“I thoroughly support the staff for doing this,” City Councilwoman Sissi Bruch said then, adding that she appreciated a proactive approach to improving stormwater quality in the city.
The city will pay the remaining $100,000 of the total $250,000 project through its stormwater fund, Boehme said.
Fecal coliform bacteria is found in feces of warm-blooded animals.
While not necessarily an agent of disease, high fecal coliform levels in creeks and streams may indicate the presence of disease-causing organisms that often live alongside the bacteria, according to Ecology.
Colony-forming units
Fecal coliform bacteria are measured in colony-forming units, or CFU, per 100 milliliters of water, Boehme explained.
State standards say no more than 10 percent of individual water samples taken from creeks like the five in Port Angeles can exceed 200 CFU per 100 milliliters.
For the 12-year study period, water samples from nine out of 13 Peabody Creek sample locations, or 69.2 percent of locations, were higher than state standards, according to city figures.
All the city’s creeks are listed as impaired by state standards in some way, Boehme said, though Peabody Creek is the worst.
“Based on that study, we confirmed that Peabody Creek was a high-priority freshwater body in the city,” Boehme said.
“Since then, we have been performing investigations on our stormwater system to determine where the best places are to install water quality projects.”
These investigations targeted a 65-acre sub-basin of Peabody Creek near Jesse Webster and Erickson parks as the area that would most benefit from the under-sidewalk filtering structures, Boehme explained.
How it works
The structures, which would look like standard storm drains built into sidewalks from the surface, would be placed under sidewalks and connected to existing stormwater pipes, Boehme said.
The filtering material acts as a microbiological ecosystem that allows the fecal coliform bacteria to be consumed by other microorganisms that live in the material itself, Boehme said.
The structures, referred to by their brand name as “Filterra” units, include space for a tree to grow on the top of the unit that would feed on the material captured in the filters, Boehme said.
‘Natural processes’
“Basically, the Filterra unit mimics the natural processes found in the forest,” he said.
The stormwater from this one sub-basin enters Peabody Creek through an outfall in the culvert through which the creek passes under Peabody Street.
Once the Filterra units are installed, Boehme said, the city intends to take samples from this outfall to see whether the filtering structures are having an impact.
“If we see a reaction, that will be a positive sign that project was a success and [that] we should consider additional installations,” Boehme said.
Boehme said he expects installation of the structures to begin next spring and take between two and three months.
“We still have to do design work on this project, which we’re doing in-house,” he said.
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Reporter Jeremy Schwartz can be reached at 360-452-2345, ext. 5074, or at jschwartz@peninsuladailynews.com.