Increased erosion resulting from increased motorboat activity on the Alagnak is a concern of river managers.
Erosion of riverbanks from river currents and waves is a natural process. However, increased wave action due to motorboats has become a serious concern over the years with an increase in visitation to the Alagnak Wild River. Actively eroding and denuded riverbanks are especially vulnerable to further wave action as high banks composed of loose sand and gravel are undercut. Visitors using motorboats can help reduce continued erosion by significantly slowing their craft in areas where erosion is evident.