Shoreline erosion due to wave action is a common problem. Mowing the lawn to the water’s edge can make the problem worse, and can encourage algae growth and other water quality problems. For example: turf grasses have shallow roots.
This allows bank under-cutting by moving water or animal burrows. Banks erode at the shoreline and may slump. Lawn fertilizers may be flushed into the water and encourage algae growth. Short grasses are not effective in filtering sediment or pollutants from runoff. Short grasses attract geese whose wastes adds pollutants to lakes.