Beach Nourishment

An alternative method of reducing or temporarily stopping excessive erosion of the natural coast is to provide a "man-made" beach and dune-bluff. Feeding sand to a coast is referred to as "beach nourishment." Beach nourishment works by reducing sand-starved conditions by supplying sand needed for waves and currents to rebuild and maintain the natural protective beach and sand bar system.⁴⁹

The supply of beach nourishment sand can come from many sources. When a coastal structure traps sand on one side, creating erosion problems on the downdrift side, the trapped sand can be dredged and moved (by-passed) around the structure. This mechanical by-passing of sand places the same sand on the downdrift shoreline that would have arrived there naturally if the structure was not present. Sand trapped by a structure can also be moved back updrift (back-passing) to the portion of the coast where it eroded. Sand can also be obtained from inland sources, like quarries, and trucked to the beach.

Beach nourishment sand must be free of contaminants that might be suspended or dissolved in the water as the sand is reworked by storm waves. Testing for contaminants can be a costly procedure. Criteria for contaminate testing is not standardized and can be inconsistent among agencies responsible for requesting the test procedures.

Erosion and reworking of nourishment sand provides three important beneficial effects. First, beach nourishment sand directly protects the natural dune-bluffs from wave attack by serving as a sacrificial dune and beach buffer zone between the waves and the previously eroding natural coast. Second, beach nourishment reduces erosion on adjacent properties by supplying sand to the regional beach and sand bar system. Both the beach nourishment project site, and the adjacent shoreline benefit from the placement of nourishment sand. Third, beach nourishment creates beaches that can be used for recreation.

With time, beach nourishment sand is completely mobilized as it moves down the shoreline providing protection to downdrift property owners as new beaches and sand bars. When all the beach nourishment sand is carried downdrift, the project site must be "renourished."⁵⁰

Beach nourishment activities are encouraged through state statute. The "Sand Nourishment Fund"⁵¹ provides a mechanism to protect and increase sand in Indiana along Lake Michigan. Coastal communities can obtain funds through their local state legislators which can then be used for (1) the deposit of sand along the coast of Lake Michigan in Indiana; (2) the design and establishment of systems that cause sand to be deposited along the coast of Lake Michigan in Indiana; and (3) the prevention or reduction of the degradation of sand along the coast of Lake Michigan in Indiana. Unfortunately, the Sand Nourishment Fund currently has no regular source of revenue.

Under another state statute, the DNR may impose a royalty fee for the removal of materials dredged from the bed of Lake Michigan.⁵² As an incentive, the NRC has by rule waived the royalty if the person authorized to dredge agrees to place any suitable dredge materials along the Lake Michigan shoreline as beach nourishment for the beneficial use of the general public.⁵³

Recently, the NRC adopted a rule to establish a general authorization (sometimes called a "statewide permit") for beach nourishment from sources landward of Lake Michigan. A person who qualifies for the general authorization may place sand for beach nourishment, either within or outside the ordinary high watermark, without obtaining a permit under the Navigable Waterways Act. Instead, a letter is provided to the agency by the person wishing to use the general authorization. In the letter, the person provides information concerning the site of origin, the site of deposit, and other pertinent information such as testing performed on the sand. Unless the DNR responds within 14 days to require full permitting or to impose conditions on the terms of the deposit, the general authorization is "deemed to have been approved and the person may proceed."⁵⁴


Nourishment sand is regularly provided by the dredging efforts of the Northern Indiana Public Service Company (NIPSCO). NIPSCO must dredge to keep its water intake at the Bailly Plant from being clogged by sand trapped updrift of the Burns International Harbor Complex. Seventy-five percent of the dredged sand is "by-passed" to Ogden Dunes and deposited on the outer sand bar . The other 25% is "back-passed" to Beverly Shores.

Four designed beach nourishment projects have been conducted in Indiana by the federal government. In 1974, 227,00 cubic yards of sand was placed in front of Mount Baldy. The second beach nourishment in 1981 was at the same Mount Baldy location using 80,000 cubic yards of sand.

Two additional nourishment activities were started at Crescent Dune near Mount Baldy in 1996. One source of the nourishment was hydraulic maintenance dredging of the Michigan City Harbor. The other was mitigation for downdrift erosion from the Michigan City Harbor breakwater constructed by the federal government in 1836.

The Michigan City Harbor channel was dredged between June and July of 1996. Ten-thousand cubic yards of the material were deposited offshore in a previously used lake-bottom disposal site for contaminated dredge material approximately 1.25 miles north northwest of the Michigan City Lighthouse. Forty-five thousand cubic yards of the Trail Creek dredge material was pumped to the Mount Baldy beach area of the Indiana Dunes National Lakeshore, west of Michigan City.⁵⁵

The Crescent Dune area east of Mount Baldy received about 53,000 cubic yards of sand as mitigation for the littoral drift losses associated with the Michigan City Harbor structures. The Corps approved a local quarry as the source of sand to be used by the contractor. The beach nourishment activity began in mid July and lasted through November 1996. Additional sand was trucked to the site in 1997 and again in 1998. The long-term plan is that beach nourishment activities, resulting in the placement of up to 230,000 cubic yards of sand, will continue at five to six year intervals for the next 50 years.⁵⁶


Geographic Information System

The Lake Michigan Coastal Coordination Program is developing a geographic information system (GIS) to assist with technical analyses of the Indiana Lake Michigan shoreline. Design of the system began with the incorporation of data from the 1986 and 1988 Coastal Situation Reports completed by Purdue University which include erosion rate, dune-bluff height, and water's edge movement. In addition, data such as aerial photograph locations, the 100 year flood elevation, and man-made lands are included. Plans are to continue to develop this coastal information system to allow for technical analyses of shoreline conditions through modeling applications. Availability of the system via the Internet is also being developed.

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