Much of what Alpha describes in the benefits of beaver dams, plant and tree root/soil interaction, revegetated river beds, and the spreading of flood waters onto plains for groundwater recharge is essentially the physics of energy dissipation. Slowing the water dissipates the energy. This is the same principle behind the benefits of mangroves to dissipate coastal storm surge flooding.
The topography of California unfortunately includes mountain ranges with deep river canyons depositing flow onto coastal plains and valleys which are overdeveloped by industrial scale agriculture and urban areas. Energy is channelized until banks are topped and levees breached.
Portions of Southern California’s coastal mountain ranges and hills are shale which can have unfavorable bedding planes from faulting and uplift over the last 10 to 15 million years. Picture this as a layer cake or lasagna tilted at 45 degrees or steeper. When angled in the downhill direction, this geologic structure is subject to slope instability. This condition is worsened by heavy saturation top soils and slopes left barren by wildfire. It is also caused by poor grading and land development practices. Much of the property damage to structures and roads from mudslides and landslides shown in the news after storms can be attributed to this. The unfavorable bedding planes are most predominant in western Los Angeles, Ventura, and Santa Barbara Counties.
Much of what Alpha describes in the benefits of beaver dams, plant and tree root/soil interaction, revegetated river beds, and the spreading of flood waters onto plains for groundwater recharge is essentially the physics of energy dissipation. Slowing the water dissipates the energy. This is the same principle behind the benefits of mangroves to dissipate coastal storm surge flooding.
The topography of California unfortunately includes mountain ranges with deep river canyons depositing flow onto coastal plains and valleys which are overdeveloped by industrial scale agriculture and urban areas. Energy is channelized until banks are topped and levees breached.
Portions of Southern California’s coastal mountain ranges and hills are shale which can have unfavorable bedding planes from faulting and uplift over the last 10 to 15 million years. Picture this as a layer cake or lasagna tilted at 45 degrees or steeper. When angled in the downhill direction, this geologic structure is subject to slope instability. This condition is worsened by heavy saturation top soils and slopes left barren by wildfire. It is also caused by poor grading and land development practices. Much of the property damage to structures and roads from mudslides and landslides shown in the news after storms can be attributed to this. The unfavorable bedding planes are most predominant in western Los Angeles, Ventura, and Santa Barbara Counties.