Case Study: State Route 99


Case Study Overview

Project: State Route 99
Location: State Route 99, WA, United States
Project Type: Roads
Application: Retaining Walls
Product Used: GEOTEX® Woven

Photo showing construction of retaining wall with the purpose of maintaining traffic flow during construction of new bridges.


State Route 99 connects the southern suburbs of Washington State to Seattle. The Washington Department of Transportation (WADOT) was called to fix a four-lane, timber bridge not capable of handling the heavy traffic flow along this roadway. Because more lanes were needed, the DOT decided to build two new bridges.


To maintain traffic flow and meet tight right-of-way conditions, the DOT built the first bridge adjacent to the existing structure allowing traffic to continue on the timber bridge. A wrapped-face retaining wall was necessary to support the weight of the road during construction The DOT selected GEOTEX® high performance woven reinforcement geotextile for use in all wall sections on both the bridge and the foundation reload wall.

Photo showing wrapped-face retaining wall using GEOTEX.




GEOTEX® provided superior hydraulic characteristics and was resistant to UV degradation making it ideal for wrapped-face retaining walls. The wrapped-face retaining wall using GEOTEX® allowed traffic flow to continue during construction while saving time and money with its easy installation.

Visit the GEOTEX® Woven product page to learn more about this Propex® GeoSolutions product.
Printable Case Study PDF
Product Data Sheets
Additional Case Studies Featuring GEOTEX® Woven