12th Ave NW Basin Drainage Project Update
Dear neighbors,
We wanted to provide an update on the 12th Ave NW Basin Drainage project. The team is planning two types of drainage infrastructure for this project: grey (underground pipes) and green (natural drainage systems).
The project team has reached 30% design for the grey infrastructure. We’ll be building upsized conveyance pipes and storage pipes along 11th Ave NW between NW 120th St and NW 122nd St and on 10th Ave NW between NW 122nd St and NW 125th St. We’ll also be installing upsized conveyance pipes on NW 125th St between 10th Ave NW and 6th Ave NW. Conveyance pipes are used to carry flows from one place to another. See the dark blue line on the map at right for the alignment of all the grey infrastructure.
All of the drainage improvements will be constructed in the right of way. If you live along the grey alignment and have planted trees or placed other items in the right of way, such as fences, we may reach out to you and ask that they be moved before construction. At this time, the earliest the construction of the grey infrastructure will begin is late 2020.
The project team is still working on selecting the streets for the green infrastructure, or natural drainage systems. The green blocks on the above map show where we are considering natural drainage systems siting. Right now, our team is completing additional hydraulic modeling work to determine the most efficient combination of green and grey infrastructure. The results of the modeling should tell us how many blocks of natural drainage systems we need to install. Once we have that information, we’ll share it with the community.
Stay connected – for more info
- Visit our project websites: www.seattle.gov/util/12thBasin
- Sign up for 12th Ave NW Basin specific email updates
- Email us at SPU_BroadviewProjects@seattle.gov
Warm regards,
Broadview Team
206-409-3651
