1	Erosion Prevention and Sediment Control Practices for Effective Construction Site Management
2	What’s Our Goal? To improve the quality of water in our creeks and rivers by reducing storm water pollution
3	Watersheds & Storm Water Pollution A watershed is an area of land that catches and drains storm water to a common body of water such as a creek, river, lake or ocean. Rain water causes surface runoff which carries pollutants through watersheds and into storm drainage systems (curb & gutters, swales, pipes, culverts, creeks, streams and rivers). Generally, this polluted runoff does not receive any treatment before discharging into our waterways.
4	Pollution Through Our Watershed
5	Common Pollutants from Construction Sites Include:
6	Impacts of Storm Water Pollution to Our Watersheds What people do upstream affects the quality of water for people downstream. Often, people don’t know they’re polluting waterways. Being aware of the problem is the first step toward the solution. Sediment is one of the biggest sources of storm water pollution in Sonoma County. Land disturbing activities, such as agricultural operations and construction projects, contribute excess sediment to our waterways.
7	Why is Clean Water So Important? Quality of water affects quality of life! All living organisms (plants, fish, wildlife, humans) depend on clean water. Clean water is essential to sustain our economic and recreational interests. Sonoma County has established a Storm Water Program to help protect and enhance water quality.
8	Sonoma County Watersheds Sonoma County has two major watersheds. Water in the Northern part of the County drains to the Pacific Ocean, mostly through the Russian River. Water in the Southern part of the County drains to San Pablo Bay, mostly through Sonoma Creek and Petaluma River. Each watershed has its own regulating authority.
9	National & State Storm Water Regulations National The Clean Water Act regulates water quality standards in the U.S. and is administered by the Environmental Protection Agency (EPA). The National Pollutant Discharge Elimination System (NPDES) is a federally mandated program intended to reduce storm water pollution. State The Porter-Cologne Water Quality Control Act regulates water quality standards in California and is administered by the State Water Resources Control Board (SWRCB). Under NPDES, the SWRCB issues General Construction Permits for projects disturbing 1 or more acres of land.
10	Local Storm Water Regulations The northern portion of Sonoma County is regulated by the North Coast Regional Water Quality Control Board. The southern portion of Sonoma County is regulated by the San Francisco Bay Regional Water Quality Control Board. In addition to the above, storm water quality is regulated by Sonoma County through Article III of Chapter 11 of the Sonoma County Code.
11	Excerpts from the Sonoma County Code §11-25; Intent “is to protect and enhance the water quality of the county’s watercourses” §11-29(a); “The release of non-storm water discharges to the county’s stormwater system is prohibited” §11-32(a); “Any person engaging in activities which may result in pollutants entering the county’s stormwater system shall undertake all practicable measures to reduce and/or eliminate such pollutants” §11-32(d); “Any construction contractor...shall implement appropriate best management practices to prevent the discharge of construction wastes…from entering the stormwater system”
12	Storm Water Violations Storm water violations are misdemeanors as well as violations of the Porter-Cologne Act and the Clean Water Act. Each day out of compliance constitutes a separate violation. Fines and penalties can reach in excess of $25,000 per day plus additional assessments. Third party lawsuits from environmental organizations can also be costly.
13	Erosion from Construction Sites Construction sites that are not effectively managed to prevent erosion and control sediment will generate polluted runoff and make construction sites muddy and difficult to work within as well as increase cleaning costs, maintenance and access problems.
14	Erosion from Construction Sites (continued) Excess sediment leaves construction sites then enters drainage ditches and storm drain pipes. The capacities of these facilities become reduced which increases the probability of flooding hazards and may pose a threat to public safety.
15	Reduce and Prevent Storm Water Pollution Implement effective construction site management through the use of Best Management Practices (BMPs). BMPs are schedules of activities, maintenance procedures, behaviors or devices used to prevent or reduce storm water pollution. Key BMPs: Educating designers and training field crews on proper installations and maintenance. Field staff should communicate with desginers to address problems at the construction site.
16	Erosion Prevention Measures Schedule work to avoid rain Preserve existing vegetation Manage storm water run-on Stabilize exposed slopes and stockpiles Dissipate energy from high velocity flows Provide training to staff and field crews
17	Scheduling Construction Work Schedule construction operations, major grading work and maintenance activities during dry weather.
18	Scheduling Construction Work (continued) Have erosion prevention and sediment control measures in place by October 15^th Prepare for rain during the wet season Monitor weather reports and forecasts: www.noaa.gov www.weather.com Incorporate erosion and sediment control measures into construction costs Phase construction to minimize the extent of disturbed areas
19	Preserving Existing Vegetation Allow the root structure of existing vegetation to keep soil in place Use construction fences to notify field crews of work boundaries Protect trees which should remain Avoid unnecessary clearing and grubbing Use existing vegetation as filter mediums for polluted surface runoff (50’ minimum)
20	Use of Orange Construction Fence This orange construction fence delineates limits of work and preserves the existing vegetation along the creek.
21	Managing Storm Water Run-on Prevent clean run-on water from mixing with pollutants on-site Redirect clean water around site Use swales and pipes to collect and convey clean water to an appropriate discharge location Avoid causing flooding conditions on adjacent properties Construct cut-off swales above exposed slopes
22	Stabilizing Exposed Slopes Create a buffer between runoff and soil Establish at least 70% vegetation coverage before the wet season Install erosion control blankets Place up and down slopes (parallel to flow), not across slopes (perpendicular to flow) Trench at top of slope and install overlapped similar to roof shingles Anchor tightly against slope but don’t stretch
23	Stabilizing Exposed Slopes (continued) Hydroseeding should be done by following this 3-step process: Step 1: Spread seed mix evenly Step 2: Cover seed mix with straw mulch Step 3: Keep materials in place Spread straw mulch Apply at a minimum of 4,000 lbs per acre (no soil should be visible) Use a tackifier or crimp into soil to keep in place
24	Unprotected Slope This is what we want to avoid; an exposed slope discharging to a waterway.
25	Protected Slope This straw mulch has been adequately applied since the ground is not visible but it still needs to be crimped.
26	Misuse of Erosion Control Blankets These erosion control blankets should be trenched in at the top and placed down the slope, not along contour.
27	Proper Installation of Erosion Control Blankets These blankets have been installed properly and the established vegetation provides additional protection.
28	Dissipating Flow Energy Provide erosion protection at concentrated (pipe) flow outlets Place 6” (min.) rock rip-rap at outlets Return concentrated flow to sheet flow Reduce flow velocities in swales but be sure to leave swales as designed before completing construction operations Establish vegetation Line with rock Install check dams
29	Improper Installation of Rip-Rap This rock rip-rap is the right size and type but placement of rock should be angular and jagged not smooth.
30	Training Staff Provide education on storm water regulations to stay in compliance and to avoid fines and penalties Train field crews to properly install and maintain BMPs Provide resources to designers Convey the concepts and importance of reducing storm water pollution not just the methods
31	Erosion Prevention vs. Sediment Control Erosion Prevention Keeps soil from being dislodged by prohibiting direct contact with high velocity water flow. Rain hits the ground at ~20 mph with sufficient energy to disrupt soil. Not allowing rain to contact exposed soil will prevent erosion problems. Erosion prevention must be practiced throughout the wet season. Sediment Control Recovers soil and other pollutants after mixing with water and becoming mobile. Polluted water is usually filtered or treated which is more costly than preventing erosion. Sediment control should be practiced year round.
32	Sediment Control Measures Silt Fences Fiber Rolls (Straw Wattles) Inlet Protection Sediment Ponds Concrete Washouts Stabilized Construction Access Vehicle and Equipment Maintenance Construction Site Management
33	Silt Fences Install on contour, perpendicular to flow Key in filter fabric into a 6” x 6” trench Place stakes 6’ – 8’ apart Wrap ends together to prevent gaps Place 2’ – 5’ from toe of slopes Avoid disturbing unnecessary areas Dispose of collected sediment before fence is breached Replace every six months or as necessary
34	Misuse of Silt Fences These silt fences have not been properly installed.
35	Fiber Rolls (Straw Wattles) Install on contour, perpendicular to flow Trench roll 3” – 4” into soil Place stakes 4’ – 6’ apart and at ends Abut ends together to prevent gaps Use on 3:1 slopes or flatter DO NOT drive over rolls Use core-weighted rolls on pavement Maintain and replace as necessary
36	Misuse of Fiber Rolls These are common misuses of fiber rolls.
37	More Misuse of Fiber Rolls Here’s more common misuses of fiber rolls.
38	Combination of Sediment Control Measures This is a good use of fiber rolls and inlet protection. Combining protection measures keeps sites clean.
39	Inlet Protection Prevent pollutants from entering inlets Install inlet filters and screens Place gravel bag barriers in gutters Keep grate elevation 6” above adjacent grade, when possible Prepare for unpaved and paved scenarios Maintain protection measures and properly dispose of collected materials
40	Unprotected Inlets These storm drain inlets need to be protected.
41	Protected Inlets Use gravel bags within gutters to prevent pollutants from reaching inlets.
42	Sediment Ponds Collect polluted runoff in a temporary basin Construct temporary earth berms to contain polluted runoff for small projects Design ponds to allow sufficient sediment storage and settling time on larger projects Provide a riser inlet and emergency spillway Maintain ponds and remove sediment as necessary
43	Concrete Washouts Construct a temporary basin for washing concrete tools, equipment and truck chutes. Place a ring of hay bales then cover with plastic sheeting to create a container Provide a clearly visible sign Cover during rain events Maintain or replace washout as necessary and properly dispose of hardened concrete
44	Proper Use of a Concrete Washout This is a good example of a concrete washout which is signed and easily accessible to workers.
45	Stabilized Construction Access Construct temporary construction access at least 50’ long, 15’ wide and 6” – 12” deep Place 3” – 4” rock over filter fabric Make sure vehicles enter and leave the construction site through the access points Install a tire wash if necessary Maintain access and sweep excess sediment from roadways as necessary
46	Proper Installation of a Stabilized Construction Access This construction access has been properly installed and keeps sediment from reaching the roadway.
47	Vehicle and Equipment Maintenance Perform maintenance and refueling activities in a contained location Place drip pans under vehicles overnight and when not in operation Inspect and repair leaks Wash vehicles and equipment in a designated and contained area
48	Construction Site Management Ensure trash and debris are deposited in garbage cans or dumpsters Cover stockpiles and material storage areas Contain paint, chemicals and other hazardous materials in an enclosed location Locate temporary restrooms at least 50’ away from inlets or waterways Have restrooms cleaned and maintained on a regular schedule
49	Opportunities to Reduce Storm Water Pollution There are many opportunities around construction sites to reduce storm water pollution.
50	Misuse of Temporary Restrooms Improper use or placement of temporary restrooms could introduce pathogens into drainage facilities.
51	Vehicle & Restroom BMP Combination This is a good use of an unfinished round-about to contain pollutants during a small rain event.
52	Remember, the goal is to prevent storm water pollution...
53	And to preserve clean water in our water ways and for our use.