The west side of the James River has sections of shoreline that erode at a rate of 1 – 2 feet a year. The erosion is caused by rainfall, slumping of vertical banks and wave action. Many owners have ignored the problem but an increasing number have to deal with it or lose septic drain fields, out buildings, roadways and even houses. Any fix is expensive and requires maintenance. We have 189 ft of river bank varying in height from 28 to 2 feet. In 2005 we had it sloped and the bottom 8 feet (6 ft high) covered with huge rocks on top of woven fabric and buried a couple feet deep at the base for a cost of $60,000. The top slope is grass covered and that has stopped erosion from rain while the rock stops wave erosion at the bottom and any resulting slumping or sloughing.
Our slope should be more gentle, but we had no choice. As a result some of the big rocks have been dislodged by wave action and need to be repositioned eventually. Meanwhile I’m going to try using polyurethane foam to fill in some exposed areas based on some work being done by BASF in the North Sea to use just the foam. It took four 10oz cans of triple-expansion Dow Corning foam over an area about 18 inches square and 2 inches thick, not as deep as I’d like. This foam needs protection from sun and it would be nice if dry sand sprinkled on top would work, but most of the sand doesn’t stick. Also, if you apply too much to damp foam, the weight will affect it. But sand was applied over the entire surface and white paint to half. Now we have to wait all year to see what the result is.