Coastal Structures
Dune Construction
Our Goal: Promote better projects along the coast that balance the use of Lake Erie as a shared natural resource along with the property owners’ need for lakefront erosion protection and the benefit of access to the lake.
Sand dune construction protects the area landward of the dune while enhancing the beach lakeward of the dune. Dunes function to protect the upland by limiting the number and force of waves reaching inland, while also providing protection from storms and strong winds.
The larger the dune, the greater the protection provided. Dunes also function to enhance beaches by periodically providing sand to the beach and nearshore area. This is usually done through wind blown transport of the materials, but if waves are large enough to reach the dune, they may remove sand and place it on the beach and in the nearshore.
Constructing a dune involves the build-up of sand directly behind a beach so that the dune has a slight to moderate increase in elevation over the beach area. Most often snow fencing or netting is placed early in the process to capture wind-blown sand, while vegetation is planted to keep the dune in place. In some cases, material or structures are placed at the core of the dune to provide a base for the accumulation of sand.  Cores can consist of biodegradable material or ramp-like structures built of treated wood with open slots for planting vegetation. Native vegetation is preferred when working on any project along the lake.
Similar to beach nourishment, any sand placed during a dune construction project should be of the same or larger grain size than the materials occurring naturally at the same location. Sand which is smaller than the locally-occurring material may be quickly eroded by wind and wave action.
 For a dune to function properly, there must be adequate room between the lake and the upland, and the dune must remain relatively undisturbed by foot or vehicle traffic. If a site has an existing sand dune, whether or not it also has vegetation, it is best to not walk on the dune to prevent it from eroding away. When existing vegetation is damaged or destroyed by foot or vehicle traffic, there is a greater chance of the dune eroding as the vegetation dies off.
 To maintain a dune, re-vegetation may be necessary should the initial plantings not survive. The area of new vegetation may need to be cut off from pedestrian traffic. Often snow fencing is a simple way to direct traffic around the new plantings. If a dune loses too much sediment during a storm event or over time, re-nourishment may be necessary.
Constructing a dune over a small area of beach may not require the assistance of a contractor, should the property owner be able to acquire the sediment and machinery necessary. The planting of vegetation and the placement of snow fencing or netting can often be conducted by a property owner or community. In most cases, however, dunes are constructed over larger areas, which are more efficiently dealt with by a contractor. In those instances, a property owner will require the services of a contractor.
Dune Construction Essential Information
Function: Provide greater protection of the upland from storm waves while also
creating a source for beach building material (i.e. storms carry sediment from
dunes lakeward).
Appearance: Slightly to moderately higher in relief than the beach area, located inland of
the shore; vegetation is often used to increase the stability of the dune while capturing additional sediment moved by the wind
Materials: Sand and cobble, dependent upon beach composition; vegetation to stabilize
Issues: For a dune to function there must be enough space and sediment; dunes should
be relatively untouched to allow for the growth of vegetation
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