Water Resources Division Management Division

Flood Control

Levees

Levees are earth structures that keep elevated waters from flooding interior lowlands. Yakima County has 21.8 miles of levees. 15.1 Levee miles are certified by the Army Corps of Engineers for different flood level events, and are maintained per Corps requirements, while the rest are orphan levees that have no certification.

Dike
Flood Plains Levees
Click on map for larger image

8.6 Miles Authorized Federal Levees

6.5 Miles PL84-99 Certified Levees

6.7 Miles Non-Certified "Orphan" Levees

City of Yakima and Terrace Heights Protected to 100 Year Flood Event

Lateral Confinement of Levees Increasing Maintenance

Yakima 1927
1927
Yakima 2004
2004
View Larger Side by Side Images

1927 Overlay2004 Infrastructure Overlay on 1927 Photo

Energy and Sediment Dispersal °Disrupted river processes
°Lateral constraint
°River attack at constraints
°Reduced area for sediment deposition

 

FEDERAL PROJECT MAPS
Certified Levees Constructed by the
Federal Government.
Operation and Maintenance Manual
 
PL84-99 PROJECT MAPS
Lower Naches River
Upper Naches River 
Non-Federal Levees Systems in
the Federal Program

Levee Owner’s Manual for Non-Federal Flood Control Works

The Levee Owner’s Manual for PL84-99 was written specifically for the public sponsors of non-Federally constructed levees, floodwalls, channels, and other Flood Control Works. It describes the proper operation and maintenance of these structures, and the assistance the U.S. Army Corps of Engineers can provide before, during, and after a flood.