Harbins Park Soil Bioengineering Project
KEMRON was tasked with the Harbins Park Soil Bioengineering Project in Lawrenceville, GA for the implementation of the restoration and repair specifications within a 1200-acre recreation and conservation park. Harbins Park experienced significant erosion damage due to vehicle use as well as bank failure and erosion along two surface water systems intersecting the park.
Historical use of the property by four-wheel drive and ATV operators created severe erosion damage throughout the park. Erosion damage included channels up to four feet deep extending over hundreds of feet in length. Site preparation involved mobilizing site support facilities, temporary utilities and the creation of an approved construction entrance with appropriate sediment management controls. An equipment and materials storage area was constructed. Following mobilization, contractor progress meetings were held prior to initiation of each major construction event. The construction was based on a contractual specifications and drawings package establishing minimum design and construction criteria. Using the conceptual level guidance and minimum design criteria, KEMRON was required to build the environmental controls to best suit the specific environmental constraints. Thus, the specifications and drawings provided the performance objectives with KEMRON providing the final environmental control structures, stream bank repair and reconstruction and site restoration to a natural structure and vegetative setting.
KEMRON repaired 10 acres of damaged areas over a two-mile access road. Mitigative measures included the placement of a straw substrate, construction of 20,000 sq ft of Core Mat erosion matting, and strategic placement of natural log diversions on all sloped areas. Once erosion repairs were complete, KEMRON completed site restoration activities at the site by re-planting with an indigenous seed mix returning the area to a natural grassy setting.
Two small rivers with relatively shear banks and seasonal high water scouring damage and bank failure intersect the park. KEMRON was tasked with reducing the impacted bank slopes to less than a 2 to 1 slope. Once the earthwork was complete, KEMRON planted 6000 tubling plantings of four indigenous woodland plant types. The combined earthwork and replanting effort provided the necessary bank stabilization to allow the stream banks to return to a natural condition while reducing erosion and bank failure into the streams. The lower reaches of the stream slopes were further armored with Type III riprap from the high water mark to the bottom of the stream channel. Another damaged area approximately 1000 ft long and 80 ft wide required a series of riprap check dam flow reduction zones. These check dams were installed through the placement of more than 1000 tons of riprap.
This project was completed ahead of schedule and on budget under a fast paced, two-month field schedule to meet the optimum winter to spring dormant planting season. All work was completed in coordination with the client’s bioengineering design team and KEMRON’s certified horticulturist under strict quality controls for seeding, fertilizing and core mat placement. Conservation protection mechanisms such as silt fence sediment controls, temporary and permanent seeding, tree protection and fencing were implemented to protect the local environment. KEMRON regraded over 10 acres of damaged area in order to repair major surface erosion damage. All soils were re-used, regraded and revegetated with indigenous common grasses and wildflowers. The projects scope of work was specifically the installation of sediment controls and revegetation in an effort to control future soil migration.
KEMRON provided site monitoring and maintenance to include watering, inspection and minor repair to drainage structures and site security to minimize trespass. KEMRON was responsible for plant warrantees and compliance inspections throughout the maintenance period.