Lower Coal Creek Flood Hazard Reduction
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The King County Flood Control District has provided funding to the City of Bellevue to address flooding issues in the Newport Shores neighborhood. The city is working with an engineering team and in conjunction with Newport Shores residents to develop a project with two components to reduce flood risks. The first component will reduce Lower Coal Creek flooding and the second will reduce street flooding.
Map of Project Area
|Flooding in Newport Shores
||An existing Lower Coal Creek culvert
The City of Bellevue and its engineering team have done a substantial amount of work to move forward on the Lower Coal Creek flood reduction project. The following information provides additional details about this work.
Schedule of Activities
The Lower Coal Creek flood reduction effort will follow this schedule:
- 2015 – 2017: Design, easement and permit acquisition.
- 2017 – 2019: Construction of new bridges (culverts) and stormwater outfalls.
Reduce Creek Flooding
Updated March 2017: To reduce the risk of flooding from Lower Coal Creek and to better allow for fish passage, Bellevue will construct new bridges at the five creek crossings in the neighborhood. The engineering team just completed the design for the upper Skagit Key bridge replacement and is preparing for construction of the bridge in summer 2017.
Construction of the new bridge will start in early June 2017 and continue through October 2017. The existing bridge at upper Skagit Key will be closed during these months, and therefore traffic will be rerouted to avoid the construction site. There will be signage and construction crew members to help redirect traffic. Please note that all residents will continue to be able to access to their houses during this construction effort.
Noise from construction is only allowed between the hours of 7 a.m. to 6 p.m., Monday through Friday; and 9 a.m. to 6 p.m. on Saturdays, except for Federal holidays and as further defined by the Bellevue City Code. Noise emanating from construction is prohibited on Sundays or legal holidays unless expanded hours of operation are specifically authorized in advance. Requests for construction hour extension must be done in advance with submittal of a permit.
The construction will take place in three phases: (1) building the bridge supports, (2) doing work in the waterway (which will require temporarily diverting the flow of water away from the creek), and (3) paving the road on the new bridge. After construction, it is possible that the bridge might “settle” into the ground due to soil types and other factors. Bellevue will pave the roads on a regular basis to minimize any large “bumps” when driving, biking, or walking onto the bridges.
The construction crew will use a variety of equipment to build the new bridge, including a drill rig and a lattice crane. Bellevue is working to minimize disruption and noise impacts of this construction effort, and residents will be able to contact an on-site Construction Inspector with any concerns or complaints. The Newport Yacht Club will distribute the contact information for the Construction Inspector in advance of construction.
The new bridge at upper Skagit Key will not be as flat as the old bridge. Instead, there will be a slight incline as you ascend the bridges and a slight decline as you descend. This will allow the bridge to be taller to help prevent debris from getting clogged, and will improve fish passage into Lake Washington. As requested by Newport Shores residents, the bridge railings will be slotted to maintain views of the creek.
Bellevue is starting the design work for the next two bridges at Cascade Key and Newport Key. Construction for these bridges is planned for summer 2018.
Reduce Street Flooding
Updated March 2017: To help prevent flooding in the streets during heavy rains, Bellevue will reroute stormwater away from Lower Coal Creek to Lake Washington. To do this, Bellevue will need to construct a new stormwater outfall into the Grand Canal, and another outfall into the Newport Yacht Club marina. These outfalls will include filters to prevent debris and litter from entering Lake Washington.
The engineering team is starting the preliminary design for these outfalls. In spring 2017, surveyors will collect data in the Newport Shores neighborhood. In spring 2017, they will conduct field work at the Newport Yacht Club. However, this field work will not interfere with access to the Yacht Club’s facilities.
The city is committed to working with residents throughout the design, permitting and construction phases of this effort.
Status Update (June 2016): On May 11, 2016, nearly 40 Newport Shores residents attended an open house to learn about, provide feedback on, and ask questions about the Lower Coal Creek Flood Hazard Reduction Project and other infrastructure efforts in Newport Shores (see photos). Thank you to the Newport Yacht Club for hosting the event and to everyone who attended this public forum and shared their thoughts (see this map of residents who participated).
During this Open House, City of Bellevue Utilities staff and engineers were stationed at five different tables that focused on: (1) New Bridges; (2) New Stormwater Outfalls; (3) Information for Streamside Property Owners; (4) Sewer System Testing; and (5) Traffic Safety at the Entrance to Newport Shores. Residents were able to provide suggestions and input regarding these projects so that the engineering teams can take them into consideration as they continue to develop the bridge designs. Below are the posters and other materials from this Open House:
Other public outreach is being planned for future stages of the project. This will include updates to this webpage, updates in the Newport Yacht Club Association’s newsletter, as well as future community forums and potential field trips.
Previous Outreach: The City of Bellevue hosted a booth at the city’s Spring Forward Expo in April 2013 and had meetings with the Newport Yacht Club Association in October 2013 and March 2014. The City of Bellevue hosted a Public Forum on May 12, 2014 at the Newport Yacht Club to hear the public’s thoughts on potential alternatives.
Below is an overview of the history of the Lower Coal Creek flood reduction effort.
||Engineering study of existing conditions; initial contact with public.
||Alternatives analysis, public involvement.
||Select preferred alternative(s); finalize pre-design and details of preferred alternative(s); community meeting to discuss preferred alternatives.
||Selection of engineering design team.
||Contracting and field investigations.
|Fall 2015 / Spring 2016
||Preliminary bridge design.
||Submittal of Army Corps of Engineers permit and completion of the draft “30% plan and design” document.
||Finalization of the “30% plan and design” document for five culvert replacements.
||Finalization of the “60% plan and design” document for Upper Skagit Key bridge.
||Finalization of “100% plan and design” document for the Upper Skagit Key bridge.
How can I stay informed?
This webpage offers the most up-to-date information on the project. Additional materials and project information will be posted on the site as the project develops. For more information, please contact: