COUNCIL AGENDA ITEM
SUBJECT:
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Engineering Design for Duck Lake Outfall
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DEPARTMENT:
Environmental Services
SUMMARY:
In June 2023, City Council approved a proposal in the amount $137,100 from the engineering firm Halff, Inc. under the terms of the City's continuing services contract RFQ 19-GS-011 - Continuing Professional Engineering Services for the engineering design, permitting, and construction documents preparation of a stormwater control structure and outfall pipe to improve drainage from an old borrow pit in the vicinity of 16th Street and Kumquat Drive sometimes known as Duck Lake. This pond receives stormwater runoff from the surrounding residential neighborhood, including via a piped connection from the stormwater treatment pond at the intersection of Regent Street and Bond Street, however the borrow pit has no engineered outfall path to a public conveyance. The proposal was to design a new control structure and outfall pipe along Lime Tree Drive so that during major storm events, the peak water stage will discharge into the 18th Street Canal and not backup into nearby homes.
This project requires permitting through the St Johns River Water Management District (SJRWMD) and potentially other regulatory agencies. In the process of responding to comments from SJRWMD, Staff and the Engineer of Record found a better, less costly way to accomplish the same end goal of providing a discharge path for Duck Lake by installing a stormwater pipe crossing Needle Palm Drive at 17th Street then relying on the existing drainage system along 17th Street to convey the discharge into the City's Pine-Orange Canal. Staff had an opportunity to test the functionality of this approach during Hurricane Milton, and no adverse impacts were observed to the downstream flow path during pre- and post-storm pumping from Duck Lake.
To design and permit this different path is a major change in scope and thus requires additional fee. Halff Inc. submitted a proposal in the...
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