Design Criteria and Constraints
Design Criteria
- Attenuate stormwater and storm surge peaks by 20% for a 100 year flood
- Maintain a functional design life of 20 years given the projected sea level rise of .41 meters and the associated increase in salinity during that time.
- Create a plant community with a Shannon Diversity Index of at least 2.5
- Reduce Total Suspended Solids (TSS) by 20%
- Remain within a $2,000,000 budget
Design Constraints
- Preserve the Gethsemane Community Fellowship Church and McDemmond Center for Applied Research
- Easily maintained by local maintenance crews
- Minimal modification to existing transportation infrastructure (railroad, highway, parking lot)
Standards
Virginia DEQ Stormwater Design Specification no. 13: Constructed Wetlands
Sec. 5: Feasibility & Design Applications
Sec. 6.1: Sizing of constructed wetlands
Sec. 6.2: Minimum pool depth
Sec. 6.5: Conveyance and overflow
Sec. 6.9: Landscaping with native flora
ASCE 45-16: Standard Guidelines for the Design of Urban Stormwater SystemsVA DEQ BMP Clearinghouse Design Specifications:
No. 9.: Bioretention Ponds
No. 11: Wet Swales
No. 13: Constructed Wetlands