A Crib Dock Can Add Value to Your Waterfront Property Shoreline
In our geographic area in northwest Wisconsin (the Apostle Islands region of Lake Superior), it's not uncommon to see what are sometimes described as "permanent docks" or "crib docks" along the shoreline. Among the twenty-one Apostle Islands, Madeline Island is home to perhaps a couple hundred of these crib docks.
Construction of these crib docks generally consists of oak cribs, pinned together with heavy iron spikes and filled with large brownstone boulders. The rock-filled cribs are then "topped" with planking, allowing a dock surface that can be equipped with mooring cleats or dock lighting, sometimes even boat davits or a winch system.
The U.S. Forest Service describes crib docks as being "capable of lasting 50 years or longer without treatment", provided that they are properly constructed and that the wood crib logs or timbers remain continually submerged. The cold waters of Lake Superior inhibit bacterial action which would otherwise contribute to rot and decay.
Lake Superior is a tremendously powerful body of water, and it is generally impractical to place temporary docks, such as roll-out docks, on the shoreline. The biggest enemies of any dock on Lake Superior are ice and waves. Rising water levels can literally lift the top off a crib dock (as Madeline Island dwellers witnessed in September of 2014, when a powerful storm tore the decking off nearly one hundred crib docks).
Crib docks are fairly expensive to build and install. The cribs are typically constructed and pinned together on land, then are hauled by barge to the point of installation. These shoreline docks require permitting with the Wisconsin Department of Natural Resources and there are other requirements for application, including provisions for recognizing the riparian rights of adjacent owners. Once the cribs are bedded on the lake bottom and filled with boulders, most dock builders recommend that the cribs be allowed to sit over a winter and spring season before decking is added. it is not uncommon to see large crib docks on the Madeline Island shoreline which cost the owner $50,000 or more to build.
Crib docks offer many advantages to waterfront homeowners. They can encourage and support fish habitat and they break wave action along the shore which could otherwise lead to bank erosion. While a crib dock is not a substitute for a well-protected mooring (such as a marina), they provide durable temporary dockage for small craft and sailboats. A crib dock would be considered an improvement and should be taken into consideration when a real estate appraiser or agent calculates the value of shoreline property.
Another related improvement would be a shoreline staircase. These are built on the bank of the lake and they connect the top of the bank with the portion of the shoreline at the vegetation line or beach. Because these staircases are exposed to wind, waves and ice, they are typically built with large dimension pressure-treated timbers set in concrete piers. Again, severe storms or ice sheets can tear a shoreline staircase off the bank.
Should you consider adding a crib dock or shoreline staircase to your waterfront property? We recommend consulting with an experienced local dock builder before making the decision to proceed with installing any shoreline structure on Madeline Island.