Comments for Ahern East Coast Drive proposed developmentJim, after reviewing the Public Hearing info for this Dunlap / Hionides request and visiting the site, I have concerns from the Public Works viewpoint, but am unsure of the proper way
to bring them up.
In their initial application to the CDB, they stated they were exempt from SJRWMD requirements and that the City was willing to waive their retention requirement. I do not know what
exempts them from WMD requirements, (adding more than 9000 ft2 impervious should cause a stormwater permit to be required), but my reading of our Code yields a pretty substantial requirement
for on-site retention (see attached spreadsheet). I don’t know why Bob may have agreed to a waiver, but without some additional documentation, I do not feel obligated to concur.
As currently graded, the property drains to the center and most of the runoff probably percolates into the ground. Although the change in runoff is only about 0.6 cfs, when developed
almost the entire volume would have to be directed into the city’s existing 12” storm sewer (~ 1.6 cfs). This additional flow could contribute to significant head loss in the pipe
and cause the inlets at the corner of Ahern and East Coast Drive to backup during a storm event. If the developer were to upgrade this pipe to at least 15” as part of his project,
this concern would be resolved.
<<Runoffcalcs.xls>>
Ricky L. Carper, P.E. Public Works Director
City of Atlantic Beach
1200 Sandpiper Lane
Atlantic Beach, FL 32233
Ph: (904) 247-5834
E-mail: rcarper@coab.us