2024 Water System Improvement

​​Project Status

To help keep area residents informed of our construction progress, we will post project updates to this site on a regular basis. Click here to see status updates.

Project Details/Neighborhood 

• 84^th Ave SE from SE 46^th St to SE 47^th Pl, including SE 47^th Pl
• 86^th Ave SE from SE 46^th St to the 4700 Block of 86^th Ave SE
• SE 47^th St from 84^th Ave SE to Island Crest Way
• SE 46^th St from 84^th Ave SE to Island Crest Way
• SE 42^nd East to West mercer Way
• Stub outs at 77^th AVE and 78^th Ave SE at SE 27^th St.

​Background

Providing safe and reliable drinking water for the community is a top priority for the City of Mercer Island and the Public Works Department. The 2022 Water System Plan Update establishes the following goals:

1. Preserve public health and safety,
2. Maintain adequate water volume for firefighting,
3. Maintain adequate water volume for basic sanitation and
4. Maintain consumptive value and water quality.

The City’s water distribution system includes more than 113 miles of water mains of varying age, size, material, and condition. Most of the system is composed of cast iron and ductile iron pipe. Some of the older cast iron piping is brittle, undersized, and known for developing leaks and breaks as it nears the latter part of its expected life. Cast iron pipe in the Mercer Island water system was primarily installed in the late 1950s and early 1960s, making it some of the oldest piping within the distribution system

Description

The 2024 Water System Improvement  project is part of our yearly water system improvement program to replace under-sized and aging cast iron water mains. We expect to replace over 6,000 LF of cast iron water mains. Along with water main replacement, this work includes two stub-outs for future connections in the Town Center, and storm drainage improvements within the neighborhood between SE 46th and SE 47thStreet west of Island Crest Way. The streets in this neighborhood will be repaved in 2025 as part of the City's residential street resurfacing program. This work also encompasses water main replacement along SE 42nd Street near the shoreline of Lake Washington, which requires additional permitting, some possible slope restoration and drainage improvements, as well as easement acquisitions.

Project Timeline

Planning/Design Q4 2023 to Q2 2024
Construction Timeline Q3 2024 to Q2 2025

Estimated Budget

$2.455 M

Contact

George Fletcher, Senior Project Manager. george.fletcher@mercerisland.gov

https://www.mercerisland.gov/WU0131