Erosion And Sediment Control Post Thomas Fire Resources and FAQs / Control De Erosión y Sedimentos post Thomas Fire Recursos y Preguntas Frecuentes
Q: What causes soil erosion in burned areas, or downstream of burned areas?
A: When active fire ends it leaves behind bare dirt or decreased vegetative cover. Because of the loss of vegetation, the top layer of soil becomes loosened, making it vulnerable to increased runoff, erosion and sedimentation.
Q: What can property owners do to manage erosion and debris impacts and minimize the risks of erosion?
A: Property owners can implement erosion and sediment stabilization practices to keep sediment and debris from impacting homes. Erosion and sediment stabilization techniques such as gravel or sandbags, hay bales, silt fences, straw wattles, log erosion barriers, erosion control mats and mulch around burned areas can be effectively used to reduce the chances of ashes and other material from mobilizing during rain events. Please refer to the following link: https://www.nrcs.usda.gov/Internet/FSE_DOCUMENTS/nrcs144p2_063808.pdf
Q: Where can I find additional resources on how to protect my property from erosion after the fire?
A: The United States Department of Agriculture (USDA), Natural Resources Conservation Services (NRCS) provides the following information and resources. Please refer to the following link for more detailed information: https://www.nrcs.usda.gov/wps/portal/nrcs/main/ca/newsroom/features/
Q: What is being done to prevent erosion and harmful runoff from impacting our watershed?
A: Local agencies are working together to assess and develop management plans to reduce sedimentation and flooding impacts in fire-impacted areas.
Q: What is a “hazard tree” and how should it be removed?
A: It is a fire-damaged tree which is dead and would pose a threat to the safety of the public and infrastructure if it should fall. Also, insect infestations in the burned trees are a hazard. Please refer to the link below for more information: https://www.nrcs.usda.gov/wps/PA_NRCSConsumption/download?cid=nrcseprd1349702&ext=pdf
Q: What are some techniques to control erosion after the fire?
A: The following are some ways of treating and preparing the soil to help control erosion.
- Hand Raking
Hand raking is a treatment for prepping the ground for mulching after the fire. Please refer to the link below for a detailed description:
- Erosion Control Mats
Erosion control mats are protective mulch blankets or stabilization mats anchored to slopes to limit erosion and enhance revegetation. Please refer to the link below for a detailed description: https://www.nrcs.usda.gov/Internet/FSE_DOCUMENTS/nrcs144p2_061751.pdf
Hydromulching is the practice of placing a mixture of water, fiber mulch and tackifier on burned slopes to prevent soil erosion. Please refer to the fact sheet from NRCS for detailed technical information: https://www.nrcs.usda.gov/wps/PA_NRCSConsumption/download?cid=nrcseprd1349704&ext=pdf
Q: What are some types of barriers that can be used to stop or contain sediment and water flow?
A: The following are some types of barriers which can prevent sediment and water flow.
- Sandbag Barriers/ Contour Sandbags
The use of sandbag barriers is one of the post-fire erosion and sediment stabilization practices to keep sediment and debris from impacting homes and downstream waterways. Sandbags placed along contour of slope to increase infiltration, reduce erosion, and help contain soil on slopes. Please refer to the fact sheet from NRCS for detailed technical information:
- Log Erosion Barriers
Logs placed on the contour perpendicular to the direction of the slope provide barriers to runoff from heavy rainstorms and are called log erosion barriers. Please refer to the fact sheet from NRCS for technical details: https://www.nrcs.usda.gov/wps/PA_NRCSConsumption/download?cid=nrcseprd1349705&ext=pdf
- Straw Wattles
Straw wattles are long tubes of plastic netting packed with straw. Wattles are used in a similar fashion to log erosion barriers. The wattle is flexible enough to bend to the contour of the slope. It is generally available from home improvement stores. Please refer to the fact sheet from NRCS for technical details: http://www.herefordnrcd.com/Straw_Wattles.pdf
Q: Can I grade or install retaining walls or other permanent improvements to stabilize my hillside?
A: Most mechanical grading or structural stabilization such as with retaining walls or other permanent improvements will continue to require a permit. Homeowners should review all such plans with the appropriate permitting agency within their jurisdiction to confirm whether or not a permit is required.