Download Stormwater Issues A

Storwater Issues
Water that runs off of
impervious surfaces
such as roads,
parking lots, or
rooftops.
Why manage stormwater?
• To prevent flooding
during heavy rains.
• To keep our rivers
and streams healthy.
• To meet state and
federal requirements.
• To provide for future
growth and
development.
Problems
Dam Top and Slopes/Faces


A dam by definition is an artificial barrier which impounds
water.
Goal: Prevent Tree Growth and Erosion

Ensure integrity of dam stays at highest level.
 Trees located on a dam may fall creating a weak point and with a
high water level, the dam could not withhold this pressure.
Dam Top and Slopes/Faces

Prevent Erosion

Stabilizing exposed soil and dirt with grass and other vegetation that has a
substantial root system and holds the soil in place.
Principle, Emergency, and WQ Spillways

Prevent stormwater from being unintentionally held, instead of
being released at the designed controlled rate and prevent
structural damage.

Water that is being held longer than 24-48 hours is creating a possible safety
issue.
Principle, Emergency, and WQ Spillways

Remove any material such as sediment, leaves, limbs, or anything
that will restrict or stop the flow of water.
Principle, Emergency, and WQ Spillways
Principle, Emergency, and WQ
Spillways

Remove any large debris to prevent runoff from being route in
alternate direction.

Used in high water elevations to discharge water out of facility and
prevent structural damage.
Inlets

Prevent stormwater from entering at an uncontrolled
rate and remove large floatable debris.


Runoff entering at uncontrolled rate increases the risk of erosion
Removing floatable material at this point reduces the chance of your
outlet structure from being clogged or restricting it’s flow.
Inlets
Positrack skid steer
with mulching
cutter head
4x4 Tractor on
slope
Chipper Crew with
Loader
Recently cut pond
Mb
Erosion Control
Matting and Blankets
Protective coverings used to establish permanent
vegetation



Protects young plants
Promotes plant establishment
Helps reduce erosion
-Temporary and permanent blankets
-All must be approved by GDOT
Blankets must be applied correctly
Blankets & sod must be anchored.
Start at top of slope and work down.
Temporary Downdrain Structure

Placement
Diversion
Anchored every
10 ft
Outlet
protection and
lined channel
Turf Maintenance
Mowing
- Remove ⅓ – ½ top growth
Fertilizer
- Apply 400 lbs 10-10-10 per acre
(10 lbs/1000 square feet)
- In 6 – 8 weeks apply an additional
90 lbs of 34-0-0 per acre
(2 lbs/ 1000 square feet)
Lime
- Apply 1 ton every 4 – 6 years or as per soil test
Ornamental Grasses





River Oats (Chasmanthium latifolia)
Maiden grass (Miscanthus spp.)
Muhly grass (Muhlenbergia capillaris
Panic grass/Switch grass (Panicum virgatum)
Indian grass (Sorgastrum nutans)
Ornamental
Groundcovers

Daylily

Asiatic jasmine

Liriope

Big periwinkle (Vinca major)

Thrift (Phlox subulata)

Iris
Herbaceous Ornamentals
- Use plants suited to wet and dry conditions
- Base planting on mature plant size
- Plant in fall or early spring
- Fertilize in early spring
- May need water during
establishment
Ornamental Maintenance
Establishment
-Plant in fall or early spring
-Spacing depends on size of mature plant
Fertilizer
-Apply 400 lbs of 10-10-10 per acre per year
(10 lbs per 1000 square feet)
Lime
- Apply 1 ton every 4 – 6 years or as per soil test Lime