CESSWI- 8 (BMPs) Questions and Answers
Bioretention - ANSWER--uses landscape features, such as plants, to provide onsite
treatment and stormwater runoff
Catch Basin Inserts - ANSWER--function to trap sediment, debris, and pollutants
Concrete Washout Area - ANSWER--contains concrete removed from
vehicles/equipment by washing and prevents it from entering storm drains or
waterbodies
Limitations= only as effective as the training of employees
Constructed Stormwater Wetland - ANSWER--structural practices similar to wet ponds
that incorporate wetland plants into the design
Cut-back Curb - ANSWER--create a place for water to pond at the back of curb while
still allowing full access to the site
Diversions - ANSWER--utilized to intercept and divert run on/off site water and off site
runoff to a stabilized outlet or treatment practice
Dry Detention Ponds - ANSWER--used to detain stormwater runoff to allow particles
and associated pollutants to settle
Dust Control - ANSWER--designed to reduce or eliminate airborne dust created by
construction and construction-related activities
Equipment Maintenance and Cleaning - ANSWER--designed to provide workers with
the training and locations for the repair, maintenance, fueling, and cleaning of
equipment so that fluids used/collected in these processes may be trapped and
prevented from being introduced to stormwater flow
Limitations= high costs, permits may be required
Existing vegetation - ANSWER--designed to stabilize soil and to remove suspended
particles from sheet flow runoff
Limitations= some regions may not have vegetation to work with
Fiber rolls/ Waffles - ANSWER--straw, mulch, etc. packed and placed into rolls that is
designed to capture sediment and reduce flow velocity
-targets sediment and hydrocarbons
Final Stabilization/Permanent Ground Cover - ANSWER--achieved when all soil
disturbing activities are completed, density of vegetation is established, as required by
permit, is established, or equivalent permanent stabilization measures have been
achieved such as asphalt, concrete, etc.
, Gabions - ANSWER--utilizing wire baskets filled with stone to achieve structural
purposes (building walls, etc.)
Headwalls/End Walls/Wing Walls - ANSWER--stabilize the soil behind them and
prevent sediment introduction into the potential runoff that will come from the headwall
inlet/outlet device
Hydromulch - ANSWER--consists of wood or other fiber in a hydraulic matrix with a
stabilizing emulsion or tackifying agent
Limitations= requires curing time, not meant for high-traffic areas
Hydroseed - ANSWER--consists of seed, fertilizer, and stabilizing emulsion applied with
hydraulic equipment to protect soils from wind and water
Limitations= may be difficult on steeper slopes
In-line Storage - ANSWER--number of practices designed to use the storage within the
storm drain system to detain flows
Infiltration Basins/Ponds - ANSWER--consists of a shallow impoundment, which is
designed to infiltrate stormwater into the soil
Infiltration Trench - ANSWER--rock filled trench with no outlet that receives stormwater
runoff. The runoff is stored in the void space between the stones and infiltrates through
the sides and bottom into the soil.
Inlet Protection at Grade - ANSWER--protects inlets that are flush with the ground, or at
grade which receives stormwater from disturbed ares or the construction site
Inlet Protection- Block and Gravel - ANSWER--promotes the settling of sediment by
pooling water. Concrete blocks are used to support the gravel.
Inlet Protection- Filter Fabric - ANSWER--designed to trap and prevent sediment from
entering the storm system by pooling water and allowing sediment to settle out. May be
used on drop or curb inlets.
Inlet Protection- Gravel Bag - ANSWER--utilizes bags filled with gravel to create a small
sediment trap upstream of a storm drain inlet where water can pool and sediment fall
out of suspension before clean water tops the gravel bags and enters the drain
Inlet Protection- Stone Cellar - ANSWER--designed to prevent sediment from entering
the drain inlet by placing a ring of stone around the inlet where water will pool and allow
sediment to fall out of suspension before clean water tops the rock and enters the inlet
Inline Stormwater Treatment Devices - ANSWER--placed inline of storm drain inlet
systems such as hydrodynamic or filter systems for removal of targeted pollutants.
Bioretention - ANSWER--uses landscape features, such as plants, to provide onsite
treatment and stormwater runoff
Catch Basin Inserts - ANSWER--function to trap sediment, debris, and pollutants
Concrete Washout Area - ANSWER--contains concrete removed from
vehicles/equipment by washing and prevents it from entering storm drains or
waterbodies
Limitations= only as effective as the training of employees
Constructed Stormwater Wetland - ANSWER--structural practices similar to wet ponds
that incorporate wetland plants into the design
Cut-back Curb - ANSWER--create a place for water to pond at the back of curb while
still allowing full access to the site
Diversions - ANSWER--utilized to intercept and divert run on/off site water and off site
runoff to a stabilized outlet or treatment practice
Dry Detention Ponds - ANSWER--used to detain stormwater runoff to allow particles
and associated pollutants to settle
Dust Control - ANSWER--designed to reduce or eliminate airborne dust created by
construction and construction-related activities
Equipment Maintenance and Cleaning - ANSWER--designed to provide workers with
the training and locations for the repair, maintenance, fueling, and cleaning of
equipment so that fluids used/collected in these processes may be trapped and
prevented from being introduced to stormwater flow
Limitations= high costs, permits may be required
Existing vegetation - ANSWER--designed to stabilize soil and to remove suspended
particles from sheet flow runoff
Limitations= some regions may not have vegetation to work with
Fiber rolls/ Waffles - ANSWER--straw, mulch, etc. packed and placed into rolls that is
designed to capture sediment and reduce flow velocity
-targets sediment and hydrocarbons
Final Stabilization/Permanent Ground Cover - ANSWER--achieved when all soil
disturbing activities are completed, density of vegetation is established, as required by
permit, is established, or equivalent permanent stabilization measures have been
achieved such as asphalt, concrete, etc.
, Gabions - ANSWER--utilizing wire baskets filled with stone to achieve structural
purposes (building walls, etc.)
Headwalls/End Walls/Wing Walls - ANSWER--stabilize the soil behind them and
prevent sediment introduction into the potential runoff that will come from the headwall
inlet/outlet device
Hydromulch - ANSWER--consists of wood or other fiber in a hydraulic matrix with a
stabilizing emulsion or tackifying agent
Limitations= requires curing time, not meant for high-traffic areas
Hydroseed - ANSWER--consists of seed, fertilizer, and stabilizing emulsion applied with
hydraulic equipment to protect soils from wind and water
Limitations= may be difficult on steeper slopes
In-line Storage - ANSWER--number of practices designed to use the storage within the
storm drain system to detain flows
Infiltration Basins/Ponds - ANSWER--consists of a shallow impoundment, which is
designed to infiltrate stormwater into the soil
Infiltration Trench - ANSWER--rock filled trench with no outlet that receives stormwater
runoff. The runoff is stored in the void space between the stones and infiltrates through
the sides and bottom into the soil.
Inlet Protection at Grade - ANSWER--protects inlets that are flush with the ground, or at
grade which receives stormwater from disturbed ares or the construction site
Inlet Protection- Block and Gravel - ANSWER--promotes the settling of sediment by
pooling water. Concrete blocks are used to support the gravel.
Inlet Protection- Filter Fabric - ANSWER--designed to trap and prevent sediment from
entering the storm system by pooling water and allowing sediment to settle out. May be
used on drop or curb inlets.
Inlet Protection- Gravel Bag - ANSWER--utilizes bags filled with gravel to create a small
sediment trap upstream of a storm drain inlet where water can pool and sediment fall
out of suspension before clean water tops the gravel bags and enters the drain
Inlet Protection- Stone Cellar - ANSWER--designed to prevent sediment from entering
the drain inlet by placing a ring of stone around the inlet where water will pool and allow
sediment to fall out of suspension before clean water tops the rock and enters the inlet
Inline Stormwater Treatment Devices - ANSWER--placed inline of storm drain inlet
systems such as hydrodynamic or filter systems for removal of targeted pollutants.
