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Landscaping at the Water’s Edge:An Ecological Approach
"Innovative Landscaping to Protect Water Quality: Reigning in runoff"
Jeff SchlossExtension Professor and Water Resources Specialist
UNH Cooperative ExtensionUNH Center for Freshwater Biology
Lake Wicwas Association Annual Meeting August 6, 2011
Center Meredith, New Hampshire
NH Lakes• Some of the cleanest and clearest lakes in the
country• However:
– Many lakes are showing signs of stress– Cyanobacteria blooms are becoming more
prevalent• Nutrients (phosphorus and nitrogen) play a large role
– UNH studies suggest as TP and TN increase so do toxins
Precipitation
Snow Pack
Wetland Storage
Infiltration
THE WATER CYCLE
Ground Water Movement to Streams, Lakes, Wetlands & the Oceans
Evaporation &Transpiration
Transpiration
Evaporation
Ocean
Snowmelt & Surface Runoff
Runoff
Stream Flow
10% 50% 55% 15%
Development Impactson the Water Cycle
Development Impactson the Water Cycle
5x
7x
18x
Carving Up the LandscapeCarving Up the Landscape
Courtesy of UCONN Cooperative Extension
Buffer Width Affects Water Quality
Importance of Layered Vegetation
Roots stabilize soils preventing erosion and allow plants to pump up water back into the atmosphere (transpiration)
Infiltration through forest duff
Transpiration
Evaporation
Forest duff and soils act as a “sponge”
High shrubs/grasses will also discourage geese from coming on shore
Trees, tall plants and shrubs can discourage invasive species from
spreading by shading
Landscaping does not have to be the problem
Let’s Change the Approach!
Let’s Change the Approach!
Landscaping can be the solution
Dealing With Home-Site RunoffPotential Contributing Waters Sources
• From Off-site– Roads, Neighboring Properties
• From Your Site– Driveways, Boat ramps, Foot paths,
Compacted surfaces, Patios – Roof Line, Gutters, Sump Pumps– Seeps
Site Drawing
Assessment&
Inventory
•Wet areas•Seeps/Springs•Paved Areas•Compacted
Areas•Point Sources
•Culvets•Drains•Sumps
•Paths/Trails•Concentrated
Flows•Flat Areas•Sloped Areas
Following the Flow
• Diversion -away from steep areas into vegetated areas
• Interruption- break up the flow so it can’t build up velocity
• Spread the flow over a flat vegetated area
• Increase groundwater rechargethrough infiltration
• Protect shore area with riparianbuffer
Dealing With Home-Site Runoff
Infiltration (Drip) Trench
Photos: AWWA
Rain barrels
Rain gardens
• Captures and soaks up storm water runoff
• Plants that tolerate temporary ponding
Rain gardens
Photos: AWWA
Photo Credit: Barr Engineering, Minneapolis, MN
Road, Driveway, or Parking Lot ScenarioWith a curb (curb cut needed)
Contributing Area From Road
Photo Credit: Rusty SchmidtDrainage Area
Infiltration Steps
Waterbars
Photo: AWWA
Photo: AWWA
Waterbar Series
Photo: AWWA
Plunge Pool/Dry Wells
Photo: AWWA
Swales and Berms
Swales and Berms
Swales Can Promote
Detention and Infiltration
Infiltration Trench
Check Dam
Minimize Imperviousness,Use Vegetation
Photo: AWWA
5x
7x
18x
Previous Example with Best Practices
1,500
1.5 X
0.062 X
13<3 X
50 ft Forested Buffer
Infiltration Trenches
Contact Informationand Resources
Jeffrey SchlossUNH Cooperative Extension133 Spaulding Hall, 38 Academic WayDurham, NH 03824(603) 862-3848 [email protected]:Extension.unh.edu/resources
Resources Links
“Landscaping at the Water’s Edge: an ecological approach” hard copy $20 http://extension.unh.edu/resources/
Pdf version (free): http://extension.unh.edu/resources/files/Resource001799_Rep2518.pdf
NH DES- A Shoreland Homeowner’s Guide to Stormwater Managementhttp://des.nh.gov/organization/commissioner/pip/publications/wd/documents/nhdes-wd-10-8.pdf
For design guidance refer to Portland Water District/ Maine DEP environmental and conservation factsheet series: http://www.pwd.org/news/publications.php#Brochures
