North Branch of Cypress Creek Stream & Ecological Restoration
Anne Arundel County, MD
CLIENT: Anne Arundel County Department of Public Works
Prime: BayLand Consultants & Designers, Inc.
SUBCONSULTANTS: Clear Creeks Consulting LLC and Underwood & Associates
CONTRACTOR: Angler Environmental LLC
Completed: Spring 2013
Construction Cost: $1,800,000
BayLand was contracted to assess the North Branch of Cypress Creek's 450-acre drainage area to find stormwater management (SWM) retrofit opportunities to treat uncontrolled and unmanaged runoff from the 40% imperious watershed. BayLand developed concept plans, cost estimates and impervious area treated for ten SWM best management practice (BMP) retrofit sites. The assessment also included concept plans for restoration of 3,780 feet of stream and drainage channels along the North Branch of Cypress Creek.
Based on the lack of available land and public SWM facilities to retrofit, the Anne Arundel County Department of Public Works (DPW) requested BayLand to assess plans for the proposed stream stabilization project to bolster treatment of upstream impervious areas and create high pollutant removal capacity within the stream and adjoining floodplain. Following presentation of the feasibility study, BayLand was contracted to create a comprehensive and innovative stormwater BMP system to include a large in-line regional stormwater wetland, floodplain water quality ponds and wetlands, and retrofitting of multiple stormwater outfalls and drainage channels with step pool storm conveyance (SPSC) techniques to maximize treatment of stormwater runoff and to reduce pollutant loads. BayLand completed all permitting, design and construction management for the project resulting in 81 acres of impervious area treatment and credit for wasteload reductions of 434 pounds/year Total Nitrogen, 96 pounds/year Total Phosphorus and 56 tons/year Total Suspended Solids for credit under the County’s municipal separate storm sewer system (MS4) permit and Watershed Implementation Plan (WIP).
BayLand managed and secured funding for a Maryland State Highway Administration Transportation Enhancement Program Grant ($650,000) and a Maryland Department of the Environment Water Quality Grant ($593,276).
- Created/Restored 7.4 acres of wetlands with 3.3-acre net gain
- Forested wetlands
- Emergent wetlands
- Seepage wetlands
- In-line headwater wetland
- Tidal wetlands
- Creation of 4.5-acre riparian forest
- Created significant ecological uplift
- Meaningfully increased stormwater pollutant reduction
- Creation of a 2.1-acre in-line stormwater wetland at the head of the project providing water quality management for the 320-acre contributing urban watershed
- Created nine stormwater wetland impoundments
- Creation of 880 feet of SPSC for five tributary/stormwater drainage ditches
- Restored 2,900 feet of unstable perennial stream channel including:
- 200 feet reach with log-boulder step pool system
- 400 feet reach with anastomosed channel system
- 1,200 feet of floodplain wetland and open water system
- 200 feet of single-thread tidal channel