Landscaping blocks not suitable for seawalls

Indiana DNR release:

COLUMBIA CITY – People who own lakefront property along Indiana’s public lakes need to know what materials they can legally use to help protect their shoreline from wave erosion.
Such information can save landowners from spending money on materials that aren't legal to use for a seawall.
Landscaping blocks, the attractive and colorful concrete blocks that can be stacked to form walls or edges, may not be used to build seawalls, warns the Department of Natural Resources (DNR).

“Landscaping blocks simply do not provide enough stability, nor do they blend in with the natural character of the lake,” said Jed Pearson, a DNR fisheries biologist who reviews permit requests for seawalls.
Only certain kinds of materials can be used legally in certain areas for seawall construction projects.

“The law is pretty clear on what can and cannot be used to build a seawall,” Pearson said. “Lake residents need to check before purchasing materials.”
Rules that govern construction of seawalls at public lakes are outlined in 312 IAC 11-1-1 of the Indiana Administrative Code.

In areas where concrete or steel seawalls are already present, landowners may be allowed to use similar materials, depending on local conditions, but only after getting a permit from the DNR. An application for a permit can be obtained and filed at www.IN.gov/dnr/water/4945.htm. The application fee is $100.
“Even in locations where concrete seawalls are permitted, the rules don’t allow the use of landscaping blocks,” Pearson said. “Back pressure and waves are likely to dislodge them.”

In sensitive areas, concrete seawalls are also prohibited because they reflect too much wave energy that can stir up the lake bed, uproot aquatic plants, and create a virtual prison wall for frogs, turtles and wildlife.
Although seawalls consisting of natural, glacial boulders may be permitted in some sensitive locations, rocks may not be used in highly sensitive areas, such as significant wetlands or along shorelines classified as “natural.”

For more information on lake rules and the permit process, contact the Technical Services Section in the DNR Division of Water at (317) 232-4160 or toll-free at 1-877-928-3755.