3/28/1995 - Laserfiche WebLink

Home Browse Search

Boa 94 PTE 70 Beth Mitchel�l,�ndsDon Donaldson March 24 ; - A 5 Page 4 incomplete. 7.1 Segmenting and offsetting - The report states that segmenting and offsetting aploars to orov de sgM rel s O the longshore curs-entf created by the pumping sochani+�,�. There has been no demonstration with the numerical model that the ponding will not exist,.and act similarly to the Midtown project and cause a significant adverse impact to the shoreline of Vero Beach. 7.2 The discussion of relative freeboard in the completeness response is incorrect. In the third paragraph there is a statement that the University study recommends that the project should provide a relative freeboard value of equal to or less than -1.3 after conetidering unit settlement.. -.In fact, the report recommends that the relative freeboard after unit settlement be greater than or equal to -1.3. The report goes on to state that, "if the relative freeboard is less than -1.3, the effectiveness of the Reef will be reduced significantly". It appears that the proposed project is contrary to this recommendation. 7.3 Consideration of short segments - Even with the segmented offset design, due to the "bridging" effect cited in #6 of the Summary and Recommendations section contained on page 26 of the report, the structure may perform as though it is*a continuous line of units, contributing to the pumping mechanism causing ponding and the potential for increased erosion. 7.4 Irregular planform of the shoreline - There has been no demonstration through the use of the numerical model that the proposed design will eliminate this possibility or what the shoreline response will be in the area between the north and south segments of the proposed project. 7.5 Swimmer safety - Rip currents - In the February 23, 1995, completeness response, the applicant relies on the predictions of the numerical model to dismiss any currents as a significant threat to swimmers and states that the model shows there is a decrease in currents landward of the structure. These statements again point to the fundamental flaws contained in the numerical modelling where the constriction of flow caused by the units and the resulting pondinq is not considered. This is also a result Of assuming a negative wave set-up on the landward side of the structure. As mentioned previously, this is contrary to the physical modelling which was supposed to be used in the numerical modelling, and the existing installation at Midtown,'Palm Beach. Swig safety remains a serious concern of the Department. 7.6 Placement of sand fill to mitigate County has adamantly opposed placement �Tl MARCH 28, 1995 adverse impacts - The of sand fill to mitigate