Minutes 10/20/2016 PELICAN BAY SERVICES DIVISION
WATER MANAGEMENT COMMITTEE MEETING
OCTOBER 20, 2016
The Water Management Committee of the Pelican Bay Services Division met on Thursday,
October 20 at 2:00 p.m. at the SunTrust Bank Building, 801 Laurel Oak Drive, Suite 302,
Naples, Florida 34108. The following members attended.
Water Management Committee Scott Streckenbein (absent)
Tom Cravens, Chairman Dave Trecker
Pelican Bay Services Division Staff Mary McCaughtry, Operations Analyst
Neil Dorrill, Administrator Lisa Jacob, Associate Project Manager
Marion Bolick, Operations Manager (absent) Barbara Shea, Recording Secretary
Also Present
Mike Shepherd, PBSD Board
Rafael Vazquez-Burney, CH2M Hill
APPROVED AGENDA (AS PRESENTED)
1. Pledge of Allegiance
2. Roll call
3. Agenda approval
4. Approval of 9/27/16 meeting minutes
5. Audience comments
6. CH2M Hill proposal for non-stoichiometric lake treatment to reduce phosphorus
7. Adjournment
ROLL CALL
Mr. Streckenbein was absent and a quorum was established
AGENDA APPROVAL
Dr. Trecker motioned, Mr. Cravens seconded to approve the agenda as presented.
The motion carried unanimously.
APPROVAL OF 09/27/16 MEETING MINUTES
Dr. Trecker motioned, Mr. Cravens seconded to approve the 09/27/16 meeting
minutes as presented. The motion carried unanimously.
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Pelican Bay Services Division Water Management Committee Meeting
October 20,2016
AUDIENCE COMMENTS
None.
CH2M HILL PROPOSAL FOR NON-STOICHIOMETRIC LAKE TREATMENT TO
REDUCE PHOSPHORUS
Mr. Rafael Vazquez-Burney, a consultant with CH2M Hill, provided a presentation on
micro-alum dosing for algae management in stormwater lakes. He provided background
information which included:
• High levels of nitrogen and phosphorus continue to persist in PB lakes.
• The source of these nutrients is run-off into the lakes.
• Algae requires both nitrogen and phosphorus to thrive.
• Limiting one of these two nutrients would drastically reduce lake algae.
• Phosphorus contained in the lake sediment continuously goes back into solution.
Mr. Vazquez-Burney provided an explanation of ultra-low alum dosing which included:
• Alum dosing causes lake phosphorus to be sequestered in the sediment.
• Aeration systems can be used to disperse the alum into the lake water.
• This process is low cost, low tech, and low risk.
• It takes approximately three weeks to complete one lake's alum dosing.
• After a dosing, positive effects (clear lake water) are immediate.
• The estimated effectiveness is six months.
• Subsequent to a dosing, phosphorus levels must be monitored to determine when the next
dosing is needed.
Mr. Vazquez-Burney suggested that the PBSD develop a test plan for a few PB lakes to evaluate
the results of alum dosing.
Dr. Trecker commented that he believes "alum dosing" warrants serious consideration.
He suggested a trial in two test lakes which have consistently high levels of phosphorus. He
emphasized that the test lakes cannot receive any other algae treatment during the trial period.
Mr. Cravens suggested that Mr. Vazquez-Burney provide the same presentation to the
full board at the November 2 PBSD Board meeting, and requested that an approximate cost of a
trial be provided as well. Mr. Vazquez-Burney agreed to attend the November 2 meeting to
provide his presentation.
ADJOURNMENT
[The meeting was adjourned at 2:50 p.m.
Lr _
Tom Cray 6'1 s Chairman
Minutes approved [ t"j as presented OR [ ] as amended ON I it"i S'/(o ] date
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