Ben Powell, Clemson Extension

Ben Powell, Clemson Extension

The Nuts and Bolts Identify the need Define stormwater, BMPs, management concerns Describe the solutions BMPs (structural and behavioral) Improving efficiency and reducing costs Discuss prevention and maintenance

Urban Stormwater Two Major Problems 1) Increase Volume 1) Lose Filtration

A Management Concern Impervious surfaces increase stormwater Volume & Velocity Need to control Flooding & Erosion

Gutter It! Moving Stormwater: Get it outa here! Curb It! Drop It! Pipe It! Ditch It!

Historical Stormwater Management

Stormwater Best Management Practice (BMP) broadly defined by [SC DHEC] as practices that have been demonstrated 1) to control movement of pollutants, 2) to prevent degradation of soil and water, and 3) to be compatible with the land use.

Stormwater Best Management Practice (BMPs) Any device (structural) or activity (behavioral) which controls and/or treats stormwater Manage both QUANTITY and QUALITY

2 Kinds of BMPs Structural - vegetated swales -infiltration systems - bioretention systems -constructed wetlands - detention basins (wet & dry) Non-structural (behavioral) -street sweeping - water conservation - soil testing - pet waste disposal

http://mainstreetportage.org/images/bio%20swale_rend.jpg

Vegetated Swale

Infiltration Systems

Bioretention Systems & Constructed Wetlands

Manufactured BMPs

Dry Detention Basin http://dhn.iihr.uiowa.edu/runoff/images

Wet Detention Basin

Poorly drained dry detention No pollution filtering Algal blooms Broken Outfall Slumping bank Eroding shoreline A Citizen s Guide to Maintaining Stormwater Best Management Practices For Homeowners Associations and Property Owners Lake County Stormwater Management Commission

Stormwater Ponds: The Basics Understand their functions to reduce your expenses and impacts

Stormwater Pond Parts & When To Take Action!- Delaware Department of Natural Resources and Environmental Control Division of Soil and Water Conservation, Sediment and Stormwater Program 302-739-9921

Conveyances Stormwater Pond Parts & When To Take Action!- Delaware Department of Natural Resources and Environmental Control Division of Soil and Water Conservation, Sediment and Stormwater Program 302-739-9921

Stormwater ponds serve 2 primary functions 1. flood control 2. pollution entrapment/treatment

Additional Functions Recreation fishing, boating, etc. Beautification Marketing / Increased Land Values

Stormwater Pond Services Pollution Control Flood Prevention Marketing/Aesthetics

Property around stormwater ponds often marketed as lake front vistas or close to Nature. = engineered stormwater treatment device SW Ponds require maintenance.

Natural Succession All ponds eventually fill in 1. Atmospheric deposition 2. Sediments in runoff 3. Aquatic vegetation growth & decay 4. Animal defecation & decomposition

So to prevent a pond from becoming a swamp 1) Control aquatic vegetation 2) Reduce sediment loading 3) Stabilize shorelines 4) Dredge periodically to retain capacity

Sediment Removal Schedules Type of BMP Sediment Removal Frequency Facility Life Span Wet Pond 5 to 15 years 20 to 50 years Dry Pond 2 to 10 years 20 to 50 years Infiltration Trench Monthly or as needed 10 years Bioretention System 5 to 10 years 10 to 25 years Vegetated Swale As needed 10 to 25 years Manufactured BMP Annually or as required 20 to 100 years

Aquatic Plants Good or Bad? 1) Shoreline plants typically beneficial 2) Other plants OK if kept limited 3) Some algae and invasive plants should be eliminated The trick: identify the plant, consult Extension or another professional

Controlling Aquatic Vegetation Physical removal Machines, textiles, dyes, elbow grease Biological control Triploid grass carp (submerged macrophytes) Blue tilapia (filamentous algae) Insects (select plants) Chemical herbicides Must possess a category 5 pesticide license, consult Extension & DPR EDUCATION & PREVENTION!!!!!!!!!!! Signage, stop plant introductions, reduce nutrient loading, and more

Nutrient Sources? lawn fertilizers yard debris, grass clippings washing the car/pressure washing eroding soils pet, wild animal feces feeding fish, turtles, ducks

More about feeding waterfowl source of Fecal Pathogens human health concern beach advisories, shellfish restrictions contribute to shoreline erosion transport invasive plants unsightly, noisy, messy Horry County Code of Ordinances Chapter 4: Article III - Sec. 4-33. Prohibition of feeding. (a) No person shall feed, cause to be fed or provide food for domestic or migratory waterfowl in residential areas of Horry County. (b) No person shall create or foster any condition, or allow any condition to exist or continue, which results in a congregation or congestion of domestic or migratory waterfowl in residential areas of Horry County. (Ord. No. 69-07, 5-15-07)

Stabilizing Shorelines Real estate is valuable! Don t let it wash away!

What s the best way to prevent shoreline erosion? Option 1: Turf Grass?

What s the best way to prevent shoreline erosion? Option 2: Artificial Materials?

What s the best way to prevent shoreline erosion? Option 3: Use natural materials!

The Clear Choice. Vegetated Buffers - prevent erosion - long lasting - low maintenance - adaptable - self-sustaining

Aeration? 1) Insurance against fish kills 2) Reduces some biting flies 3) Limits growth of toxic planktonic algae Reduce costs => run fountains/aerators at night only

Reducing Stress on structural BMPs Innovations to reduce stormwater volume pervious surfaces rain water harvesting rain gardens green roofs, etc.

Go Pervious

Rainwater Harvesting Rain Barrels Cisterns

Rain Gardens Slow it down & Photo: Center for Watershed Protection (www.cwp.org) S p r e a d i t o u t! Photo: NC State Cooperative Extension (www.bae.ncsu.edu/stormwater)

Behavioral BMPs Prevent pollutants from entering the drainage system Reduce maintenance costs for structural BMPs Green your Grounds

Behavioral BMPs Street sweeping Covering dumpsters Pet waste disposal stations Trash receptacles Signage (no feeding fish/ducks/turtles, no dumping) Proper disposal of yard debris Protect kitchen oil/chemical storage Redirecting irrigation and much more

THANK YOU! Discussion?