State of the Beach/State Reports/IN/Shoreline Structures
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"Because Lake Michigan is a navigable water of the United States, permits are required pursuant to the Rivers and Harbors Act for the placement of piers, wharves, jetties, breakwaters, and similar shoreline structures. Before 1970, permits were not required under federal law shoreward of an established harbor line. A permit is also required for the placement of a pier or wharf on the shore of Lake Michigan from the Indiana Department of Natural Resources pursuant to IC 14-29-1-8. [UPDATE: The Natural Resources Commission adopted rules to assist with the evaluation of permit applications for construction activities along and within the shoreline of Lake Michigan. These address both emergency construction and permanent construction. Issues considered include environmental impacts, hazards to safety or property, and shoreline dynamics. Please see 312 IAC 6-7 and 312 IAC 6-8 that became effective in February 2001.]"
The USGS publication Our Changing Landscape: Indiana Dunes National Lakeshore discusses erosion issues at that location, causes of the erosion (armoring of nearby shoreline), and efforts to mitigate it. From that report:
In Indiana Dunes, the 18-mile shoreline retains much of its natural character. Adjacent to the park's beaches, however, the shoreline has been altered by the construction of harbors and industrial complexes and the use of rip rap (large boulders) to protect the shore. Of the 41 miles of shoreline between Michigan City, Ind., and the Illinois border, more than half have been altered to protect private residential or industrial properties. Structures, such as the jetties at Michigan City, Burns Harbor, and U.S. Steel, interrupt the normal longshore (parallel to the beach) transport of sand. The beach is built up as sand accumulates on the updrift side of structures; the beach erodes as sand is then removed on the downdrift side.
Just as people can delay, but not reverse, natural processes, people can also accelerate such processes. A case in point is the use of breakwaters in the vicinity of Burns Ditch and Michigan City. When the transport of sand is interrupted along a coast, erosion can increase, such as occurs to the west of the breakwaters at Burns Ditch, and sediment deposition can increase, such as occurs on the east side of Bethlehem Steel on Cowles Bog Beach. The Michigan City breakwaters cause deposition on the city's Washington Park beach while causing erosion of the beach in front of Mount Baldy.
The majority of Indiana’s shoreline is parkland with little likelihood of future construction, and much of the rest of the shoreline has been stabilized. For example, the western portion of Indiana’s shoreline is heavily industrialized and largely protected by seawalls and breakwaters.
In 1974, a 13,000-foot rock revetment was placed along the shoreline of Beverley Shores to prevent the road and homes from collapsing into Lake Michigan.
Examples of shore perpendicular structures along Indiana's coastline include: (1) Michigan City Harbor jetties; (2) Port of Indiana; (3) breakwalls at the U.S. Steel-Gary Harbor complex; and (4) the Indiana Harbor and Ship Canal complex. Examples of shore parallel structures along Indiana's shoreline are: (1) rock revetment at the Town of Beverly Shores; and (2) sheet steel breakwall system at the Town of Porter, Dune Acres, and Ogden Dunes. The longest shore parallel structures are found west of Gary along the USX steel mill facilities.
In general, though, there is a lack of an adequate geographic information system (GIS)-based inventory of shoreline structures. Without a regularly-updated inventory, it is difficult for the state to determine legal ownership and condition of structures along the shoreline. The lack of such an inventory also hampers the state’s ability to provide current information and technical assistance to individual homeowners and local communities.
The Fiscal Year 2017 Civil Works Budget for the U.S. Army Corps of Engineers provides $4.62 billion in gross discretionary funding for the Civil Works program. This budget lists proposed projects and the associated budget justification by state.
Perception of Effectiveness
The Influence of Coastal Structures discusses shore perpendicular and shore parallel structures and warns:
On the downdrift side of man-made structures, if sand (littoral drift) is not abundant enough to maintain wide beaches and broad off-shore sand bars at a particular location, erosion rates may be higher there compared to other parts of the coast, even though the same wave energy and lake levels are present at both sites. The deficit of sand may be due either to natural or man-made conditions.
Erosion rates usually increase dramatically on the downdrift side of a new structure as a result of severe sand-starved conditions created by sand being retained on the opposite (updrift) side of the littoral barrier. When no input of sand is available to replace sand that continues to move away from the structure in the downdrift direction, beach widths become narrow and the offshore sand bars lose height and width. This allows more wave energy to reach the shoreline, increasing erosion of the erodible beach and dune-bluffs.
Public Education Program
Living on the Coast, from the U.S. Army Corps of Engineers, describes how natural processes affect the coast, including changes in lake levels, storms and storm surges, waves and wave climate, transport of sediment, ice on the shore, shoreline erosion, lakebed erosion, and movement of water on the land. The booklet also describes how to protect coastal investments by adapting to natural processes, restoring a natural shoreline, moderating coastal erosion, armoring the shore, stabilizing bluffs and banks, controlling surface water and groundwater, building environmentally friendly shore protection structures, and working with engineers and contractors. The final section covers risk management and the economics of protecting your coastal investment, including shoreline property features and value, government regulations to protect a coastal investment, costs of shore protection, and accounting for climate change.
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