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While currently open as of this writing, Coulon Beach swim area was closed during the Memorial Day weekend and the first above 80-degree day of the season.
Coulon Beach Park swim area was closed on this sunny Memorial Day weekend because of high bacterial counts. It was one of only two beaches on Lake Washington closed for this reason. Unfortunately this has become more common in recent years, with Coulon’s swim area sometimes closed for weeks at a time.
Renton’s Coulon Park swim beach was closed while most local beaches were open during this warm holiday weekend.
While it’s clear that ducks and geese are contributing to the problem, it’s less obvious to Park visitors that storm drains in western Renton Highlands, the Landing and even I-405 are also contributing to the problem by adding pollution to “Johns Creek” which empties next to Coulon’s swim beach.
Renton has been working for decades to improve the water quality in Johns Creek, and a Stormwater Management Action Plan (SMAP) is in place to improve it. Renton Stormwater utility fees, along with grants when they can be obtained, pay for this work.
Johns Creek is not the only creek that carries Renton’s surface water into Coulon Park; Kennydale Creek deposits Kennydale’s surface water about a mile to the north. But in addition to emptying further away from the swim beach, Kennydale Creek flows mostly in a natural creek bed open to the sun and air, which helps reduce bacteria levels. Johns Creek flows through many pipes and culverts, only in open air as it nears Coulon Park.
So to keep our swim beach open, businesses and residents in Renton Highlands, the Landing, Paccar, Southport and parts of North Renton should help keep our street gutters clean and spread the word that whatever flows into storm drains can flow right into the Coulon Beach Swim area.
The following photos and maps give more information about this little-known creek and the plans in place to improve it.
The usual suspects; ducks and geese typically get the blame for Coulon Beach swim closures
This bridge crosses Johns Creek and connects the swim beach to the boat launch area.
Looking north from Coulon Park’s Johns Creek bridge.
Looking south from Coulon Park’s Johns Creek Bridge
A salmon slowly makes its way upstream in Johns Creek, just north of the Coulon Park Bridge
Standing on the dock surrounding the swim beach, the swim area is on the right. The outfall of Johns Creek is on the left, identifiable by the trail of foam. The boat launch is left of the foam in the picture.
The only easy public access to Johns creek is at Coulon Park’s “Creekside Shelter.”
From the “Creekside Shelter” a few stone steps lead visitors to the creek
The milky-colored stagnant Johns Creek does not look inviting for wading and splashing, unlike the typical clear water in Kennydale Creek, Honey Creek and May Creek
This retention pond between Coulon Park and Southport marks the entrance of Johns Creek into Coulon Park
Johns Creek runs through a retention pond adjacent to this power tower
Upstream of Southport, Johns Creek runs parallel to the railroad and gets fed by storm drains and culverts
This retention pond on Houser Way collects water from Houser and from I-405, and then sends it into Johns Creek
Johns Creek passing though Houser retention pond
I-405 retaining walls have dozens of drain pipes that send water into Johns Creek
At least five drain pipes can be seen in this photo that dump water into Jones Creek
A Johns Creek tributary runs between Houser and Paccar
Johns Creek looks like a series of ponds, culverts, storm drains, and manholes on this stormwater utility map of Houser Way, I-405, and Sunset Ave. Water from western Renton Highlands is carried into Johns Creek via culverts under I-405. This map can be found on the City’s website here.
More of the Johns Creek stormwater collection system, with linkages into Renton Highlands
This part of the map shows how water drains from the Windsor Neighborhood into Johns Creek
And this is how Highbury Park connects to Windsor neighborhood (and then to Johns Creek. Highbury Park retention system will soon be getting a $1,300,000 project to improve water quality in Johns Creek as part of a Stormwater Management Action Plan.
Highbury Park retention vault is a near-term retrofit in the Stormwater Management Action Plan. Other Highland retention ponds will be updated in the coming decades.
The stormwater retention vault in the Highbury Park neighborhood is underground, accessible through this manhole cover. The Stormwater Management Action Plan will retrofit this retention system with features that improve water quality flowing into Johns Creek.
This map, from the Johns Creek SMAP, shows the boundaries of the drainage basins in Renton, and highlights the Johns Creek basin
This Department of Ecology map shows water quality in Johns Creek and its outfall in Lake Washington in red, meaning it’s Category 5-303d, requiring a Stormwater Management Action Plan.
Thanks for this very interesting information Randy. I knew some of it, and learned a lot more from your post. Seeing the murky Johns creek while crossing the bridge always make me sad for the wildlife, like the poor salmon in your picture.