Apocalyptic Erosion Control: Sustainable Soil Strategies under El Niño and Drought Conditions
The contradictions inherent in two extreme climatic conditions – drought and El Niño - exacerbate soil erosion and water quality issues. El Niño conditions generally result in above-average rainfall, increased risk of erosion but also greater vegetative growth. In droughty conditions, this increase in biomass can result in more intense burns of dormant or dead vegetation and thereby accelerated erosion due to changes in the physical, chemical and biological properties of soil. Research has shown that as burn intensity increases, so does the time that it takes for a watershed to recover its normal hydrologic function. As a result - with population growth and expansion of communities into the urban interface - the risk of flooding and air quality impacts that affect human health and safety, as well as community infrastructure, may be prolonged for many years following the incidence of wildfires of high burn intensity.
So it appears that the confluence of drought and El Niño are wildfires, which increase soil erosion and accelerate erosion and flooding. But in general construction activities, the need for soil stewardship - and the erosion control best management practices that support it - is even more important during times of drought and above-average precipitation. During drought, how do we achieve final stabilization under the Construction General Permit? Conversely, how do we strengthen our erosion and sediment control plans in anticipation of El Niño precipitation? The author will provide examples of sustainable strategies – and their implementation – under field conditions of drought, El Niño and wildfires.
The takeaway message of this presentation is that while there are some differences associated with preparing for and remediating the water and air quality impacts of climatic extremes, storm water pollution prevention strategies need include long term planning for sustainable solutions to soil erosion.