Highway Runoff Manual

Publication Number
M 31-16
Publication Version
M 31-16.05
Publication Date
Manual Manager
Alex Nguyen
Originator
WSDOT HQ Design Office, Highway Runoff Unit
Subject
Planning and design of stormwater management.

The Highway Runoff Manual (HRM) provides guidance to direct the planning and design of stormwater management facilities for existing and new Washington State highways, rest areas, park-and-ride lots, ferry terminals, and highway maintenance facilities throughout the state. The HRM establishes minimum requirements and provides uniform technical guidance.

Revision History

M 31-16.05 April 2019

Supplement February 2016

M 31-16.04 April 2014

M 31-16.03 November 2011

M 31-16.02 May 2010

June 2008

M 31-16.01 March 2007

2006 October

2006 May

2004 March

1995 February

Traffic fatality crashes on Washington public roadways

increased 56% in March 2021 compared to March 2020.

11,906 incidents responded to

by WSDOT’s incident Response teams during the third quarter of 2021, nearly 6% more than same quarter in 2020.

WSF ridership was nearly 5.7 million in the first quarter of fiscal year 2022,

which was 1.6 million (38.3%) higher than the corresponding quarter in FY2021