Introduction to Stormwater BMP's in North Carolina

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The Good, the Badand the Muddy!

Kurt BlandBland Landscaping Company

*with slides provided by NCSU

Building and Facility Owners

Facility Managers Elected Officials Environmentalists Saltwater Fishermen Freshwater Fishermen Hoteliers Hospitality Workers Tax Payers

Parents Grandparents Surfers Water-skiers Boaters Farmers Drinking well users Scientists Healthcare providers Trout fishermen Water drinkers!

Stormwater BMP Maintenance & Inspection

Second largest estuary in the U.S.

The Outer Banks barrier islands restrict outflow of run-off

Runoff gets trapped and pollutants cause problems like Red Tide

Here in the Triad, we sit at the edge of one of the most precious resources in

the country. Our actions do matter!

They prevent this type of “stream” from carrying pollutants into our drinking water supply and our marine estuaries.

Trout require:◦ High oxygen levels◦ Clean water◦ Cool water

Stormwater runoff:◦ Contains sediment that kills forage and clogs their

gills◦ Is proven to have a higher temperature than trout

adapt to◦ Contains high nutrient loads that disrupt

ecosystem functions and reduce water quality

This is a NASA image of Hurricane Floyd, taken September 15th, 1999.

Where did they go?

The left is the Neuse River, the Right is the Trent River. Both areas were flooded, but one has a highly developed watershed and the other has a more

natural watershed.

The convergence of the Pamlico Sound with the Atlantic Ocean. Remember, the Pamlico is one of the most sensitive estuaries in the United States. Our sounds are second only to the Chesapeake in size and importance. The fish

that breed here are consumed by humans and are forage for key species such as Blue Fin Tuna, Tarpon, and Humpback Whales to name a few.

By treating stormwater on site, we lessen the effect of flash and we retain more of the pollutants?

Would they have contained twelve inches of rain?◦ No, not all of it, but when managing floods, the

amount of impervious surface in a watershed is an important factor.

◦ As our state population grows, and more of our forested lands are disturbed, we lose natural ecosystem benefits and have to recreate them.

GREEN (ALIVE) GRAY (DEAD)

Grassy swales that cleanse run-off and absorb nutrients.

LID Curbless streets to promote sheet-flow.

Constructed Wetlands that mimic nature.

Rain Gardens/ Bioretetnion Cells that soak up run-off.

Rainwater Harvesting to use for irrigation.

Riparian Buffers to slow the flow.

On-site treatment of quality and quantity.

Rip-rap swales. Curb and Gutter

funneling. Reinforced Concrete Pipe

to move water quickly. Culverts to ditches or

streams that accelerate flash flooding.

Massive regional infrastructure that make private issues public.

Hydrology Botany Biology Horticulture Wetland Ecology Soil Science Plumbing Grading

Design Vegetation

Management Pest Management Labor Management Equipment

Resources Trained and

Certified Personnel

Specialized landscape and site features designed to manage stormwater quantity and quality.

Structural, vegetative or management practices used to protect and improve our surface and groundwater.

Landscape system that treats, stores and reduces stormwater runoff.

These systems treat the stormwater run-off problem at the source and reduce the propensity of streams and rivers to “flash”.

Wet ponds Stormwater

wetlands Bioretention cell

or raingarden Level Spreader Permeable

pavement Green roofs Rainwater

Cisterns

Dry detention basins

Grassy swales Sand filters Riparian buffers Infiltration

devices Cartridge filters

Clean Water Act of 1972 (Enabling legislation) Phase I began in 1990 for 6 communities in

NC with +100k persons Phase II began in 1999 for all MS4

communities but was stalled until 2006 with passage of Session Law 2006-246 (MS4 = Municipal Separate Storm Sewer Systems)

NC DENR, DWQ rules◦ http://h2o.enr.state.nc.us/su/

NPDES_Phase_II_Stormwater_Program.htm Local Municipalities interpret and

enforce the legislation. This is where it gets confusing!

EPA Storm Water Penalty Authority◦ EPA may seek up to $32,500 per day per violation◦ Current maximum for an Administrative Penalty

Complaint is $152,500◦ Penalties above $152,500 are sought through a

judicial referral to the Department of Justice◦ Historically applied to construction sites, but has

also been used in MS4 violations. (MS4 = Municipal Separate Storm Sewer Systems)

EPA, the U.S. Attorney’s Office for the District of Delaware, and the States of Utah and Tennessee entered into a consent decree in September 2005 with Wal-Mart to resolve storm water violations at its store construction sites across the country.

Under the terms of the consent decree, Wal-Mart will be required to use qualified personnel to oversee construction, conduct training and frequent inspections, report to EPA and take quick corrective actions. Wal-Mart will also pay a $3.1 million civil penalty to the United States, Tennessee and Utah, and spend $250,000 on an environmental project to protect sensitive wetlands or waterways in one of nine affected states.

Doesn’t hold water for proper draw down time (24 – 72 hours)

No machinery access to slopes Slopes were sloughing off, causing

more erosion Spotty coverage of green plant

material Cost $11,000 to fix

Good access Items found included diapers, a CD

case, yard clippings from the neighbor and a TV remote control

Nearly impossible access Dead plants Too many of the wrong plants Too overgrown – tree growing in inlet

area Not enough grass on slopes

Plants require special care and selective removal◦ no trees on pond dams, ◦ no cattails, ◦ right plant-right place◦ high marsh versus low marsh

Goose control – limit open water and line of site. Geese fear predators on the bank.

Sunshine is needed to break down pollutants.

Entry and exit points need to be kept clean – water needs to flow as it was intended to.

Builds in fore-bay Clogs draw down

orifice Suffocates wetland

plant crowns Redirects sheet

flow into channeled flow

Clogs rip rap dissipators

Sediment ponds are not the same as SWBMPs

Sediment from adjacent parcels can ruin SWBMPs

The standard is to capture “First Flush” which is, in most areas, 1” of rain.

Other than wet detention basins, a properly working SWBMP should take 24 – 72 hours to drain. (Mosquitoes take about 72 hours to reproduce.)

If the SWBMP is on co-owned property and it fails, the members can be jointly responsible.◦ Financially◦ Legally

Failure can be expensive:◦ Damage to adjoining properties◦ Cost to re-construct◦ Legal expenses◦ Permitting fees

SWBMP’s should have clear & separate maintenance agreements for liability reasons. Don’t assume the landscaper is handling it! (They may not be certified.)

Frequent review of site conditions by trained professionals is both valuable and inexpensive.

Removal of Stormwater BMP material currently does NOT have to go to hazardous material waste site, but that may change.

Was it installed correctly? Is there deferred maintenance? How much $$$ is in the budget for SWBMP

maintenance and repair? Maintenance and upkeep is the number one

measure to avoid staggering repair bills, but nothing can entirely eliminate the risk of failure.

Thank you for your attention and your time today!

Kurt BlandBland Landscaping Company

Inc.kbland@blandlandscaping.co

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