The fenced stretch of the Cross Kirkland Corridor between NE 52nd Street and 108th Avenue NE was not closed for trail work. The gravel path sits on top of a regional sewer pipe. The fall closure, which King County scheduled to begin September 8, 2026, is meant to repair a failing City-owned stream culvert that runs under that pipe, along with the slope around it. That culvert is where this year-long run of closures began.
Anyone who has used this section since last fall has watched it close, reopen, close for a day, and close again. Each of those closures traces back to one pipe and one small stream.
The Pipe Under the Gravel
The pipe is Section 14 of King County's Eastside Interceptor, known in project documents as ESI-14. The County describes the Eastside Interceptor as one of the largest conveyance pipes in the regional sewer system. It carries untreated wastewater from local municipal systems between Kirkland and Renton to the South Treatment Plant, where the water is cleaned and released into Puget Sound.
The County's July 2026 environmental checklist gives the scale. ESI-14 is an 84-inch pipe that carries about 2.6 million gallons of wastewater a day in dry weather. Under the trail, the big pipe crosses above a 24-inch City of Kirkland culvert, running perpendicular to it. The culvert empties into a steep ravine with a small stream, about 1,200 feet from Lake Washington.
So in this one spot, a very large pipe sits on top of a small, damaged one, inside a slope that has been moving. Everything that has happened on this part of the corridor since 2025 comes from that arrangement.
How a Stream Sample Became an Emergency
The City of Kirkland says its 2024 water quality testing found elevated bacteria in Houghton B1 Stream. Further investigation traced the bacteria to a leak in the Eastside Interceptor. King County engineers also found a sag in the pipe that raised the risk of structural failure. The County's checklist describes the same leak, which it says was identified in 2025, as wastewater leaking into the damaged culvert. The City calls the waterway Houghton B1 Stream. A County map in the same checklist labels it "Unnamed Houghton Slope B Stream." Both names refer to this ravine.
On September 16, 2025, the City announced that City Manager Kurt Triplett had issued an Emergency Proclamation. It responded to King County's declaration of urgency and gave the City maximum flexibility to support the repair. The City's release said that without immediate action, the compromised pipe could fail and send an uncontrolled wastewater overflow into Lake Washington.
"The City's emergency proclamation underscores the seriousness of this situation and ensures we can act quickly to safeguard public health, the environment, and our community infrastructure," Triplett said in the release.
That release expected about two weeks of full trail closure, then partial access and occasional closures over the following weeks. Work was set to begin as early as the week of September 29, 2025. The project ran much longer than that first estimate.
Twelve Months of Open, Closed, Open
King County's project page lists its bulletins in order, and together they show how the work actually went.
| Bulletin date | What the County announced |
|---|---|
| Oct. 15, 2025 | Joint rehabilitation on ESI-14 underway |
| Dec. 11, 2025 | Trail to temporarily open as early as Dec. 11 |
| Dec. 29, 2025 | Trail to close again as early as Monday, Jan. 5 |
| Jan. 13, 2026 | Wastewater diverted to a temporary above-ground pipe |
| Feb. 13, 2026 | Pipe repair complete, trail opening soon |
| March 18, 2026 | Trail closed near NE 52nd Street on Tuesday, March 24 |
| July 17, 2026 | Public comment on the environmental review open until Aug. 3 |
| Aug. 4, 2026 | Culvert construction starting soon |
| Aug. 25, 2026 | Culvert repair work starts Sept. 8 |
The February bulletin divides the project in two. Crews had repaired six joints in the sagging pipe from the inside, using mechanical joints to seal it. To keep sewer service running during that work, they built a temporary bypass of pumps, generators, and a pipe about 3,000 feet long, welded on site. The bypass carried flows out of ESI-14, around the work area, and back in downstream. The County said in February the trail would open as early as Friday, February 27.
Fixing the pipe did not finish the job. The County left the 3,000-foot diversion pipe in place on the west side of the trail for the next phase. The City said the excavated access points would stay covered with steel plates and fenced until that work began. Through the spring and summer, the long gray pipe beside the gravel came from the first repair and was being kept for the second.
Why the Trail Closed Again After the Pipe Was Fixed
The new seals stopped the leak. They did nothing for the ground the pipe rests on. The County's checklist lists the conditions around the culvert: separated and displaced culvert joints, erosion and scour near the outlet, voids around the culvert, localized slope instability, and a rockery wall under the ESI-14 pipe and embankment that is deteriorating and moving. Concentrated stream flows add channel instability. The checklist says stabilizing the culvert, the slope, and the stream near the outlet protects ESI-14, the trail, and infrastructure downstream.
The culvert has been running on temporary fixes since the emergency. Crews first grouted three 6-inch pipes in at the inlet and ran them through the culvert. Those were later replaced by the 12-inch flexible pipe that is in place now. The permanent repair will remove it.
The County's planned permanent work includes:
- Lining the existing 24-inch culvert with an 18-inch liner and grouting it in place
- Repairing or replacing damaged culvert sections near the outlet
- Injecting grout to fill voids and stabilize the soil around the culvert
- Building a new gravity block wall downstream of the outlet, with a drop structure at the outlet
- Rebuilding the streambank with buried riprap, boulders, cobbles, and a grade control structure made of small woody material
- Removing the roughly 3,000-foot temporary diversion pipe and restoring disturbed ground, including areas disturbed during the joint repairs
The City expects tree planting and equipment removal after the culvert repairs are done. The City's earlier notices said crews would return "this summer." The County's August schedule moved the start to September.
What the Fall Closure Looks Like From the Trail
King County's August 25 update lists what to expect during this phase:
- A full trail closure lasting three months
- A posted trail detour
- Work on weekdays from 7 a.m. to 8 p.m., with heavy equipment noise during permitted hours
- 24-hour lights and pumping for the temporary diversion pipe, plus noise from the generator that powers the pumps
- Odors at diversion sites
- Sewer service continuing in surrounding neighborhoods
The County says the repair will take three months, and no reopening date has been published yet. The most recent County update we could find is dated August 25 and describes the September 8 start as a plan. Check the King County project page for current status before heading out.
The County's detour map labels NE 52nd Street, Lake Washington Boulevard, Lakeview Drive, NE 68th Street, 106th Avenue NE, and 108th Avenue NE. It marks both trail detour points and a "steep trail detour point." Neither the County nor the City has published turn-by-turn directions, so the posted signs at each end of the closure are the best guide. The steep-section marker is worth noting for anyone pushing a stroller or riding a loaded bike.
Questions about the work go to King County project contact Emanuel da Silva at 206-296-7432 or [email protected]. That is the number on the County's August notice. Older City pages still show an earlier number. For City questions about the corridor closure, the contact is Tuan Phan at 425-587-3843 or [email protected]. The City's Cross Kirkland Corridor page links to email updates for the 5.75-mile corridor, which is part of the regional Eastrail network.
When the fencing comes down, the gray diversion pipe should come down with it. The County's plan is to remove the temporary pipe and equipment and restore the disturbed ground on both sides of the trail. The City expects to plant trees once that is done.
If you live near the Houghton section of the corridor and want to know how a long public works project could affect the timing of a sale or purchase, Andrew MacGillivray is happy to talk it through with you, calmly and with no pressure. Let's Connect.
