Stormwater Quality Management Committee
Clark County Regional Flood Control District
600 S. Grand Central Pkwy. Las Vegas, NV 89106

SILT FENCING - Silt fences are used as a sediment control practice. Silt fences are intended to be installed where sediment-laden water can pond, thus allowing the sediment to fall out of suspension and separate from the runoff. It is not intended to be an erosion control practice. Improperly applied or installed silt fences can increase erosion. Silt fences should be constructed at the edge of the construction site parameter. Silt fences and filter barriers should be inspected weekly and after each significant storm event. Any required repairs should be made immediately.

STRAW BAILS & FIBER ROLES- Straw bales and fiber rolls can also be used as a sediment control practice. They are intended to be installed where sediment-laden water can pond, thus allowing the sediment to separate from the runoff. It is not intended to be an erosion control practice. Straw bales and fiber rolls should be constructed at the edge of the construction site parameter or to protect stockpiled materials. Straw bales and fiber rolls should be inspected weekly and after each significant storm event. Any required repairs should be made immediately.

BERMED WASHOUT PITS - Bermed washout pits should be used for cleaning concrete equipment. Washout stations can be a plastic lined temporary pit or bermed areas designed with sufficient volume to completely contain all liquid and waste concrete materials plus enough capacity for rainwater. The designated area should be located away from storm drain inlets, or watercourses. For small cleaning jobs, manually rinsing equipment into a wheelbarrow, plastic bucket or pail, and then empty the bucket into the concrete washout area.

STORMWATER DETENTION /RETENTION BASINS - Stormwater Detention/retention ponds are erosion control structures commonly installed to prevent erosion and to keep stormwater on construction sites. These structures control erosion by diverting water flows from erosion prone areas. The topography of the erosion prone area must be suitable for the installation of a detention/retention basin system.

CHEMICAL SPILL CONTROL - Spill containment should be implemented anytime chemicals and/or hazardous substances are stored in drums or tanks. Substances may include, but are not limited to fuels, lubricants, soil binders, paints, solvents, coolants, and sewage. Spills of materials or chemicals should be contained and cleaned up immediately. Secondary containment systems must be able to hold the volume of the largest container in the storage area, plus provide sufficient additional capacity for storm events.

STOCKPILED CONSTRUCTION MATERIAL - Protection of stockpiles must be implemented whenever there is a potential for transport of materials by a water source (forecast precipitation or any non-storm water runoff). Protect stockpiles from stormwater run-on using a temporary perimeter sediment barrier such as berms, silt fences, fiber rolls, covers, sand/gravel bags, or straw bale barriers, as appropriate. Stockpiles left on site should be covered, stabilized, or protected with a perimeter sediment barrier prior to the onset of precipitation. Keep stockpiles organized and surrounding areas clean. Implement dust control practices as appropriate on all stockpiled material.

Bagged materials such as cold patch, concrete mix, and other materials with the potential to pollute runoff should be placed on pallets and under cover. Repair and/or replace covers, and perimeter containment structures as needed.

Examples of Poor BMP Implementation:
EXCESSIVE SEDIMENT DEPOSITS - This picture demonstrates excessive track-out at the entrance of a construction site. Implementing track-out controls can reduce offsite tracking of sediment and other pollutants. Areas of track-out should be cleaned-up by sweeping or vacuuming. Limit the points of entrance/exit to the construction site and require all employees, subcontractors and others to use them. Implement construction access stabilization using aggregate or constructed/manufactured steel plates with ribs for entrance/exit access.
POORLY MAINTAINED DROP INLET PROTECTION - This picture demonstrates how a poorly maintained drop inlet is one of the leading causes of sediment entering the storm drain system. Gravel bags, silt sacks or dandy bags should be used to intercept runoff, reduce flow velocity, and provide some sediment removal from the construction site. It is important to maintain and inspect inlet protection devices after each storm event, and routinely throughout the construction project.
IMPROPERLY INSTALLED STORM DRAIN INLET PROTECTION - This picture demonstrates the isolation of a storm drain inlet in a public street. Isolating a storm drain inlet in a public street accepted by an Agency is not allowed. Stormwater runoff entering the storm drain inlet can result in ponding into road traffic or onto erodible surfaces or slopes, or overflowing onto the sidewalk. Protection of storm drain inlets are only allowed within the boundary of the construction site itself where sediment laden surface runoff may enter a storm drain inlet and watercourses. Blocking a storm drain inlet with surface BMPs in the public right-of-way outside the permitted project boundary is only allowed temporarily during street washing activities. Once street washing is completed BMPs must be removed.
POORLY MAINTAINED SILT FENCES - This picture demonstrates a poorly maintained silt fence. When inspectors visit construction projects, they often find silt fences installed incorrectly or poorly maintained. A properly installed silt fence holds water back long enough so that much of the sediment from runoff settles out on the construction site. Silt fences and filter barriers should be inspected weekly and after each significant storm event. Any required repairs should be made immediately.
POOR TRASH REMOVAL AND HOUSEKEEPING - This picture demonstrates poor trash removal at a construction site. Practice good housekeeping and keep your site clean. Collect site trash regularly, especially before rainy or windy conditions. It is important to perform routine inspections of your site, including storage areas, dumpsters, stockpiles and other areas where trash and debris are collected. Close trashcan lids and dumpster covers before rainy or windy conditions.
EXPOSED CONSTRUCTION MATERIALS AND CHEMICALS - This picture demonstrates how exposed construction materials and chemicals are susceptible to runoff and may enter a storm drain system. Practice good housekeeping and keep your site clean. Bagged materials such as cold patch, concrete mix, and other materials with the potential to pollute runoff should be placed on pallets and under cover. Repair and/or replace covers, and perimeter containment structures as needed.

NO SECONDARY CONTAINMENT FOR TANKS AND CHEMICALS - This picture demonstrates how unprotected fuel, oil, or chemical tanks without secondary containment is the leading cause of contaminated soil. Spill control procedures must be implemented anytime chemicals and/or hazardous substances are stored on site. All contaminated soils must be removed and managed as hazardous substances, if applicable, in accordance with applicable laws and regulations.

Back to top

Photos courtesy of the Nevada Division of Environmental Protection Storm Water Branch
 

Search | Weather | Contact Us | Home

About SQMC | What is Stormwater Pollution? | The Storm Drain System
Community Programs | Monitoring Programs | Best Management Practices
Federal & State Regulations | Brochures & Multimedia | Awards & Recognition
Stormwater Links

Copyright © 2012 SQMC. All rights reserved. Information deemed reliable but not guaranteed.
Neither the Stormwater Quality Management Committee nor the Clark County Regional Flood Control District
is liable for any errors or inaccuracies in the information provided through this website.