Hillside Erosion Solutions: Rock, Retaining Walls, or Drainage for a Steep Front Yard

A steep, eroding clay hillside with culverts needs a permanent fix. Rock armoring (4-inch minimum) creates a "no-mow" zone and invites weeds; herbicides near creeks are restricted. Retaining walls (3 ft high, ~50 ft) cost $4,500–$6,000 but allow mowing and can create level space for a future patio. DIY segmental walls (Versa-Lok, Keystone) are feasible. A rustic log timber wall is a lower-cost alternative. Drainage pipe from culvert to culvert helps but doesn't solve slope instability. For safety and usability, walls are the best investment.