SonomaCountyRecovers: Official recovery information for Sonoma County fires

Rain Ready

Stormdrain Wattle

Preventing ash and debris from entering waterways is critical as we enter the rainy season.  Tools such as wattles, screens and sandbags are commonly used to:

  • Slow the flow and turbidity of runoff 
  • Filter runoff 

People who live in burned areas, or downhill of burned areas, should be aware of increased risks for:

  • Flash Flooding: Normally, rainfall is absorbed by vegetation and soils, reducing runoff. However, wildfires remove vegetation and may leave soil unable to absorb water, creating flash flood conditions. Flood risk remains significantly higher until vegetation is restored—up to 5 years after a wildfire.
  • Mud and Debris Flows: Debris and ash, along with other sediments, can be picked up in flood waters and form mud and debris flows.

Multiple, federal, state, regional and local agencies are preparing for the potential impacts of the recent wildfires on urban and rural communities. These agencies are taking action to protect private property and critical infrastructure with the following actions:

  • In urban areas, the City of Santa Rosa and the County of Sonoma are cleaning and checking storm drains, and installing straw wattles and sandbags to prevent debris from entering storm drains.
  • In rural areas, the County is checking and installing debris-capture devices in culverts and ditches along rural roadways.
  • CAL FIRE crews, the City, and the County are clearing fire debris from streams and storm water channels to reduce flood risks.
  • The Sonoma County Agricultural & Open Space District, Sonoma County Regional Parks, and City of Santa Rosa Recreation & Parks are assessing their properties within the burned areas for hazardous conditions including downed and damaged trees and areas where erosion may affect streams and watersheds.
  • The Sonoma County Water Agency will be installing rainfall and stream gauges in watersheds in burned areas and working to install radar equipment to improve early warning forecasts for residents in high-risk areas.
  • Install straw wattles to prevent debris, ash and erosion from flowing into waterways. Straw wattles can be picked-up from local hardware stores.
  • If you see something (flooding, mud and debris flows), say something – call 911
  • Monitor your surroundings, and have an emergency plan in place.
  • Stay informed: Listen to local radio stations, and sign up for Nixle and SoCo Alerts. Make sure that the emergency alerts on your cell phone are activated (on smart phones, go to “Notifications” and make sure the Emergency Alerts notification is turned on).

After a fire, windborne material such as ash and soil from paddocks with inadequate ground cover may be blown into streams. Once in the water, organic materials provide ideal food for bacteria and algae. These organisms grow rapidly using up all free oxygen in the water (it becomes anaerobic) and putrefaction results. Symptoms are dark water, a bad smell and black scum around the water’s edge. Horses and other livestock find such water unpalatable. Thick scum around the water’s edge may also prevent animals accessing the water. It is believed the water is not poisonous to livestock, but it may be harmful to young or weak stock.

  • Fire ash contains microscopic particles (dust, dirt, soot) that can be deposited on indoor and outdoor surfaces and can also be inhaled if the ash becomes airborne. Unless tested, the ash is not classified as a hazardous waste, however it may contain traces of hazardous chemicals such as metals (lead, cadmium, nickel, and arsenic), asbestos (from older homes or other buildings), perfluorochemicals (from degradation of non-stick cookware), flame retardants, and caustic materials. For these reasons, it is advisable to be cautious and avoid any unnecessary exposure to the ash.
  • Fire ash may be irritating to the skin, nose, and throat, and may cause coughing and/or nose bleeds. Fine particles can be inhaled deeply into lungs and may aggravate asthma and make it difficult to breathe. If the ash contains asbestos, nickel, arsenic or cadmium, then exposure is a particular concern because these substances can cause cancer. Because the substances in the ash vary, it is always best to be cautious.
  • Given the scale of the burned area, it will be impossible to prevent the migration of ash and debris into creeks, and the concentrations of hazardous materials is unknown.
  • Multiple agencies are working together to prevent fire-related debris, pollutants and sediment from being carried into our storm drains, creeks and rivers.

The goal this winter is to prevent ash and debris from entering the waterways. You can help by taking simple steps by placing straw wattles, hay bales, and mulch around burned areas to reduce the chances of ashes and other material from washing into streams.

Increased rain runoff in burned areas can cause mud and debris flows. A group of local and state agencies are working to identify, notify, and implement protective measures in areas that may be at risk.

Creeks and streams located near burned areas are at a higher risk of flooding, due to increased rain runoff. Additionally, this runoff can carry sediment and debris which can block channels and culverts.

  • Watch for unusual movement of water, land, and debris during or after rain. Have an emergency plan and leave your property if it becomes unsafe during or after a storm.
  • Minimize soil and slope disturbances. Ash, leaf drops, downed trees, and remnant burned vegetation all play a role in protecting the soil and slopes following wildfire.
  • Work with your neighbors. Runoff, erosion, and debris flows have no boundaries.
  • Private roads require more maintenance in the first few winters following wildfire. Clear debris upstream of culverts as possible, and check culverts for clogging after every storm. If culverts or other road drainage structures do not appear to be functioning properly, consult a professional.

For additional information, please visit  www.sonomarcd.org/resources/fire-recovery/

  • The goal this winter is to prevent ash and debris from entering the waterways. You can help by taking simple steps by placing straw wattles, hay bales, and mulch around burned areas to reduce the chances of ashes and other material from washing into streams.
  • Remember that everything that is outside drains to creeks and streams. Don’t use leaf blowers or hoses to remove ash and debris.
  • In the coming months, consider consulting a professional before implementing permanent erosion measures.
  • Wear protective gear whenever you work in burned areas.
  • Multiple agencies are working together to assess and reduce the risk of flooding and to prevent fire-related debris, pollutants and sediment from being spread into our storm drains, creeks and rivers.
  • In urban areas, the City of Santa Rosa and the County of Sonoma are:
    • Increasing street-sweeping activities
    • Cleaning and checking storm drains
    • Installing wattles and sandbags to prevent debris from entering storm drains
    • Hydro-seeding to stabilize soil
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