SR 503 Drainage Improvements

Project news

  • The drainage improvement project will be combined with the installation of a Variable Message Sign (VMS) board, which provides traffic information to the traveling public.  
  • Construction is scheduled to begin summer 2018
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Needs & benefits

In summer 2018, contractor crews working for the Washington State Department of Transportation will remove and replace the drainage system under State Route 503, between mileposts 1.20 and 1.60, in Clark County.

Installed in the 1980’s, the existing drainage system that runs along the stretch of SR 503, between Northeast 87th Street and Northeast 95th Street is failing, and in need of improvements. Over the course of the past 25 years, as traffic volumes increased through this area, the amount of dirt and debris from cars and commercial trucks has also increased, and settled into the drainage system, clogging it.

During heavy seasonal rainstorms, the existing drainage system is overloaded, and water flows over the roadway. With the installation of the new drainage system, water will flow into a drainage detention facility, creating a safer roadway surface for drivers. 

In addition to improving the drainage system, crews will install an electronic VMS board, which provides traffic information to the traveling public. 


  • Spring 2018 – Project advertised for competitive bidding.
  • Summer 2018 – Construction begins
  • Fall 2018 – Construction will be complete. 


The total estimated cost for construction of this project is between $500k and $700k. This project is funded by both state and federal.


Devin Reck – Project Engineer

Celeste Dimichina – WSDOT Communications