Mashuda’s reconstruction of Crow’s Run Stream replicates the stream’s natural form, with zigzagging “meanders” and regions of shallow, rapid flow, or “riffles,” that alternate with pools (deeper, slower-flow areas).

Mashuda Corp. of Cranberry Township, Pa., is one excavating and grading firm that has dedicated substantial effort and resources to mitigating negative environmental impacts of its highway projects. Mashuda, a member of AGC and the Constructors Association of Western Pennsylvania (CAWP), received the Beaver County Conservation District’s 2001 General Contractor of the Year Award for its conservation efforts on a project for the Pennsylvania Department of Transportation (PDOT) in Beaver County, Pa. The project required realigning and relocating an existing unsafe roadway, which in turn resulted in realigning two township roads, relocating a stream, and replacing five wetlands and three separate structures. The stream relocation marked the PDOT’s first use in the area of a design process called “fluvial geomorphology” (FGM), which has shown a better success rate than traditional methods in preserving ecosystems.

THE SCIENCE OF STREAM DESIGN
In accordance with PDOT regulations, the Mashuda crew relocated a 1,700-foot portion of Crow’s Run Stream using an FGM design collaboratively determined by the design firm Skelly & Loy and PDOT. Although FGM was new to Beaver County, Pa., West Virginia and some western state DOTs have used the process with success. The design replicates the stream’s natural form, with zigzagging “meanders” and regions of shallow, rapid flow, or “riffles,” that alternate with pools (deeper, slower-flow areas). The new stream has a narrower channel, thereby providing better flow than more traditional relocation designs, moving sediment naturally through the system, and creating a better environment for the stream’s inhabitants. The design also calls for plantings to stabilize the earth around the stream and to cool the water for the stream’s denizens. Using a backhoe, Mashuda excavated a ditch and, every 75 feet or so, dug pools ranging from 2.5 to 5.5 feet deep. The crew used a backhoe with a special attachment for rock placement to solidly and strategically plant the stream’s rocks.

FGM BASICS
The FGM techniques and concepts used for the Crow’s Run Stream stem mainly from the work of one man. David Rosgen, considered one of the nation’s foremost experts on stream restoration and hydrology, has spent many years using field data to guide successful stream restoration and stabilization projects that do not compromise the stream’s natural behavior. The Rosgen Classification system is used to predict stream behavior and help prescribe appropriate restoration measures based on specific stream characteristics and parameters.

ADDITIONAL HABITAT-ENHANCING FEATURES
Besides adhering to the project’s strict erosion and sedimentation controls and relocating the stream, Mashuda also replaced five wetlands ranging in size from one to 1.5 acres each and even constructed a “raccoon throughway” to the stream. The throughway is basically a 42-inch diameter dual-cell pipe that passes under the roadway. One cell is higher than the other, like an elevated flood plain, to allow land animals to pass through and cross the road safely, without risk of being hit on the highway.

RECOGNITION OF CONSERVATION EXCELLENCE
Mashuda’s excellent work on the project did not go unnoticed. John Paul Sherfle with the Beaver County Conservation Authority met with Ralph Mashuda, president of Mashuda, and inspected the project site. Sherfle was impressed by the firm’s creative efforts to preserve the Crow’s Run ecosystem, which exceeded federal and state regulation requirements. “Mashuda is truly sensitive to environmental hazards,” Sherfle says. “Where possibilities exist for negative environmental impacts, (Mashuda) avoids crossing streams and wetlands without taking proper actions first.” Sherfle was so favorably impressed that the Beaver County Conservation Authority presented Mashuda with a rare and special conservation award for its work. Mashuda has been a member of the CAWP for more than 50 years. The CAWP, an AGC member, represents more than 200 companies involved in the heavy and highway construction industry.

—By Jodi Torboli , CAWP manager of industry communications

FOR MORE INFORMATION
Contact Jodi Torboli.
Call: (412) 343-8000
Online: jtruver@cawp.org
www.cawp.org