Prince George’s County Stream Restoration On-Call
Prince George's County, MD
AMT has provided on-call services to the Department of the Environment for a variety of stream restoration and outfall projects. For the last 20 years, AMT has provided close to 100 task orders in support of the County’s Stormwater CIP.
1622 Tucker Road (Henson Creek Tributary) Outfall & Stream Stabilization: AMT provided stabilization design for 170 LF of highly eroded urban streambank. The goal was to prevent further bank erosion while restoring land to an adjacent property, reduce sediment yield and improve the riparian buffer. The selected NCD utilized various in-stream structures including rock step pools, floodplain benches for sediment to deposit and rock weirs. A riparian buffer restoration, including invasive species eradication and reforestation, was included in the design providing ecological uplift. Innovative techniques such as geogrid reinforced vegetated soil lifts were utilized. A FSD was also performed.
Regency Village (Henson Creek Tributary) Stream Restoration and Bank Stabilization: The goal of the project was to restore the banks of the stream, improve in-stream habitat and provide a defined riparian buffer to prevent erosion and protect various pieces of infrastructure along the reach including a pedestrian bridge and a children’s play area. AMT also provided a full H/H study utilizing TR-20, TR-55 and HECRAS to determine impacts to the floodplain area.
Calmos Street (Cabin Branch) Streambank and Outfall Stabilization: To help eliminate and stabilize the eroded embankment, AMT proposed stabilization using a Versa-Lok Shoreline retaining wall (150’ long x 8’ high). AMT designed in-stream restoration structures, cross vanes and rock vanes; provided H/H analysis; developed all construction plans and details, phased sediment control plans, planting plans, permitting, specs, costs; and bid documents.
Boniwood (Butler Branch Streambank Stabilization): Project required restoration and stabilization of a failed 20-ft high by 200-ft long streambank. Channel bank was stabilized by IRR at bankfull elevation and with a 2-ft wide planting bench; the bank above the IRR incorporated Vegetated Geogrid Stabilization to the top of bank. Using NCD techniques, in-stream structures included 3 rock vanes; one log-dam structure as grade control; a stream-bulkhead measure involved using demolished and fallen trees from the site to help stabilize and provide definition to the inner-bank. Hydrology was performed using GIS-Hydro ultimate conditions; hydraulic analysis involved existing and proposed floodplain analysis for Water Surface, Velocity and Shear Stress comparison was performed using HEC-RAS 4.0. This stream is classified as Tier II water of high quality which required enhanced E&S controls be implemented in the design to ensure minimal stream impacts.
Parkway Drive (Walker Branch) Stream Restoration: Design for the replacement of existing culverts with two bottomless 12’ span x 6’ rise ConSpan culverts to safely pass the 100-year peak discharge of the contributing watershed; 200 ft of bank stabilization using a combination of NCD in-stream structures and vegetative stabilization. Included IRR toe, step-pools, rock cross vanes, soil lifts and coir fiber rolls. The overbank floodplain area was replanted and riparian buffer restored.
Parkside Drive (Northeast Branch) Streambank and Outfall Stabilization: AMT provided design services for the stabilization of a severely eroded 24-in diameter culvert outfall, downstream banks incorporating hard armoring (imbricated rip-rap), vegetative (live fascine bundles, tree plantings) stabilization and site sustainability methods.
