What the Experts Say

David L. Schultz, P.E.
Various monitoring reports and commentary

“For15 years, I have regularly observed dozens of Undercurrent Stabilizer installations. At every site I have studied, a successful shore protection function is evident.

“Undercurrent Stabilizers do not affect the environment in the same manner as traditional shore protection measures (walls, revetments, groins, etc). Other structures stand tall against nature, which ultimately dooms them to failure from the relentless forces of wind and wave. Undercurrent Stabilizer systems more closely mimic the shape of the natural beach platform, making them very permeable to the littoral current. Their low profile geometry does not achieve success by trapping sand, as with traditional groins, but by preventing the landward migration of storm-generated scour troughs.

“Undercurrent Stabilizer Systems perform so well that beach growth occurs at locations that are damage zones for other shore protection structures, and where the “old school” asserts the greatest negative impacts will be found. The low profile geometry of this system greatly reduces the magnification and concentration of wave energy in front and at the flanks of their placement, which is an unmitigated design flaw of traditional structures.

“Monitoring surveys to date show that greater gains in beach elevation and extent are often found on adjacent stretches of beach, rather than in front of the stabilizers themselves.

“Undercurrent Stabilizers are effective in protecting, and even elevating, the beach it was intended to protect. Furthermore, they perform this function at no detriment, and have actually shown benefits, to adjacent downdrift beaches

“The low profile cross-section of these structures and their placement along the bottom mimics the desired natural slope of the beach and generates a fraction of the turbulence and scour that accompany other shore protection structures. They remain in place when facing liquefaction forces, preventing the landward migration of scour troughs during significant storm events.

“Because of these findings, stabilizers should be defined separately, in and of themselves, as a unique type of shore protection structure. The results of this study indicate that Undercurrent Stabilizers should be recommended for shore protection needs over traditional methods, and their permitting requests treated fairly. They should also be considered for mitigation efforts, when needed to counteract the negative effects of large or more damaging marine structures.

“The most important finding of this study is that elevation changes are related to a profile’s proximity to stabilizers. Additionally, beaches located between two stabilizer fields show profoundly positive results, indicating a superposition of benefits from the installations of either side.

“The greatest elevation gains were achieved downdrift of the larger Sylvan Beach stabilizer installation, at the specific locations where the regulators and academicians insist the greatest damages are expected, according to their theories.

“These findings confirm that the theories implemented by stabilizer design are valid.

“Because of these results, as well as the data from other monitoring surveys I have been involved with, I must restate my assertion that the established ways of thinking must change among regulators and scientists to incorporate this new paradigm of shoreline processes and control. The repeated, positive results of Undercurrent Stabilizers worldwide provides an opportunity…to preserve and protect [our] most valuable and unique resource—[our] beaches.”

Dr. David A. Barnes, Dept. of Geology, MWU
Various Monitoring Reports:

“There is no indication of measurable negative impact to adjacent shore reaches within the study area resulting from the net accretion of nearshore (to approximately 500 feet offshore) sediment around the experimental structure during the monitoring period.

“Lake level rise during 1998 to near record highs at the time of the spring 1997 survey—more than 1.5 feet above long term average and approx. 1 ft above lake level at the time of the pre-installation survey.

“Consistent profile volume gain measured in the vicinity of the experimental shore protection structure and significant foreshore/backshore accretion with no apparent negative impact down drift must be viewed as success in almost any context.”

“Although beach profile change attributable to small scale, shore-perpendicular shore protection structures is not normally expected to extend this distance offshore, clear quantitative profile volume gain in “long” profiles in the vicinity of the experimental structures is shown. The net result is a substantial positive profile volume gain in the vicinity of the experimental structure both up- and down- net annual long shore drift direction.

“Unconventional groin effect mechanism is suggested by the persistent profile volume gains in the net down-drift reach well beyond the … extent of the experimental structure. The new result is a substantial positive profile volume gain in the vicinity of the experimental structure both up and down-net annual long-sore direction.

W. Thomas Straw, Chairman, Dept of Geology, WMU.

“In addition to the Tawas and Douglas test sites, investigation of previous installations of Undercurrent Stabilizers has also been conducted. A number of these installations have caused dramatic positive results. The installations are not only causing changes in the bottom topography between the structures; they are causing the beach and inner nearshore zone north and south of the Stabilizers to gain sand.”