Although it’s no consolation to people in our community who lost their homes, the Kincade Fire was very different and less destructive than the 2017 fires. Firefighters and fire experts confirm our observations that it was a fast-moving wind-driven fire. This will mean a lower impact on water quality and vegetation regrowth after the fire.
In 2017 the conditions were hotter and the vegetation drier after multiple years of drought. This caused the 2017 fires to burn much hotter than the Kincade fire in most areas. In the Mark West Springs area, much of the soil was heated to the point where all organic material burned up in the top 6 inches of soil. This makes the soil far more erosive and debris flows more likely.
Fire experts refer to three levels of burn intensity by how thoroughly it burns vegetation with green ash being the lowest intensity, grey ash being a moderate intensity and white ash being the highest fire temperatures that incinerate all leaves, needles and small branches of trees. In a large part of the Kincade burn area, the tree canopies are not completely burned off and in many areas the tree canopy is partially or mostly intact. The lower intensity is due to higher moisture in our plant community than in 2017 and not having 100+ degree weather as we had in 2017.
In 2017 we read USFS research reports that found that using large-sized wood chips is the least expensive erosion control solution that created the best conditions for native tree and plant recovery while inhibiting invasive plants. We used large 3-6” wood chips at 50% coverage on several properties with highly erosive soils and documented the performance over the winter, and found they reduced or prevented erosion. If you are removing hazardous trees after the fire have the tree company set chipper for larger chips and then broadcast the chips over burned slopes rather than leave a pile behind. We found it to be hard work spreading chips from a pile versus flinging them over 100 feet from a chipper! Workers can move the chute across slopes to prevent it from completely covering the ground in any one area. The chips also slowly release organic matter to the soil and help it recover faster after a fire.
At Riverkeeper we’re gearing up to assist in the recovery with our erosion control expertise by installing erosion control products to contain potential toxic material from burned homes and vehicles. Sonoma County is stepping up to support the recovery and is working on priority lists for preventing toxic-laden runoff based on proximity to waterways. We hope to be working with affected property owners in the next two weeks. We’re also gathering resources and donations so we can help people who do not have the means to address erosion control. We will also offer consultation for those with crews seeking advice on how to address erosion. Stay tuned.