Item 9AAGENDA ITEM # 9A
JULY 13, 2009
July 6, 2009
MEMORANDUM
TO: The Honorable Mayor
and Members of the Commission
FROM: Jim Hanso
City
SUBJECT: City Manager' Report
Study of Possible Consolidation of Wastewater Plant Flows with Neptune Beach; The City
of Neptune Beach has made a decision to upgrade their wastewater plant to meet the new TMDL
(nitrogen) standards rather than sending their wastewater to Atlantic Beach for treatment. This
decision is made after several months of study by consultants and staff from both cities.
Atlantic Beach will eliminate the Buccaneer Wastewater Plant and route those flows to the main
wastewater plant which will be upgraded to meet new standards and will have expanded capacity
as a result of the upgrades. Atlantic Beach's expanded plant will have the capacity to handle
normal flows from both Atlantic Beach and Neptune Beach. Consolidating the flows would
require Neptune Beach to upgrade the lines in Neptune Beach and Atlantic Beach to transfer the
flow northward. However, there would be a long term savings because Atlantic Beach can
handle the additional flow without needing any additional personnel. The only cost to Atlantic
Beach would be for additional electricity and chemicals. Neptune Beach could eliminate all of
their wastewater plant operating costs with the exception of electricity for a lift station to pump
the waste northward. The cities reached a general agreement on most of the terms of a proposed
contract including the approximate cost for treatment.
The problem with the combining of flows was during major rainstorms. Atlantic Beach has put
considerable money into repair and maintenance of the sewer collection system in recent yeazs.
While considerable work is still needed, the increase in wastewater flowing into the plant
approximately doubles during major rain events like Tropical Storm Fay last fall. In Neptune
Beach, the amount of storm water coming into the sewer collection system more than quadruples
during these major events. While the City of Atlantic Beach plant will have the capacity to
handle Neptune Beach's wastewater during normal conditions and for a flow increase that would
be similaz to Atlantic Beach's during major rainfall events, it could not handle the increased
volumes seen in Neptune Beach in the last year. Neptune Beach has indicated they do not have
the funds to make repairs to their system to bring storm water flows in line with Atlantic
Beach's. Consequently, they determined that the combination of the two wastewater systems is
not desirable.
AGENDA ITEM # 9A
JULY 13, 2009
A report dated June 5, 2009 from HDR, Engineering Inc. is attached for further information. The
cost to Atlantic Beach for the additional engineering to evaluate the consolidation with Neptune
Beach is $11,000.
Cars Parked in the Right of Way; the subject of cars routinely being parked in the City right of
way in grassed areas in violation to Code provisions was recently discussed at a workshop. No
decision was made on any change to the ordinance or to take enforcement action. City staff
conducted a count of the number of vehicles in the right of way in the evenings to quantify the
problem and that summary report is attached for your information.
AGENDA ITEM # 9A
JULY 13, 2009
~~ MEMORANDUM
Subject: Additional Evaluation of Neptune Beach WWTP Interconnection to COAB
WWTP -Supplement#1 to Technical Memorandum for Task Order Number 2
- Preliminary Investigation: Diversion of Wastewater Flow From Neptune
Beach to the City of Atlantic Beach -
Prepared for: City of Atlantic Beach, Florida
Prepared by: J. Collins Engineering Associates, LLC (JCEA) & HDR Engineering, Inc
Date: June 5, 2009 Revised June 9, 2009 & June 10, 2009
General Discussion
In May 2009, both the Cities of Atlantic Beach (COAB) and Neptune Beach (CONB) met to
further discuss the possibility for CONB to transfer their wastewater to COAB for treatment and
disposal at the COAB Wastewater Treatment Plant (WWTP #1). Under TM#2, CONB would
cease to treat any wastewater on site and would convert their facility to a regional pump station
with flow equalization. The wastewater flow rate was proposed to be 500,000 gallons per day on
average. During the recent meeting, CONB confirmed that a capacity of 550,000 gallons per day
would be required and that CONB would desire to eliminate or minimize the need for flow
equalization.
In order to address the interconnection more closely, both HDR and JCEA have conducted more
in-depth studies to address the increased WW flow (ADF from 0.5 MGD to 0.55 MGD) and the
best method to address the peak flows. The first work item was HDR contacted CONB (ATM -
CONB'S Engineering Consultant) and requested that CONB develop the potential or estimated
peak flows that could be anticipated at the CONB WWTP and eventually at COAB WWTP# 1.
CONB (ATM) responded with the following response and questions:
Prior to moving forward with additional evaluations at CONB, Neptune Beach would
need to know the following information in order to make an informed economic decision
that the joint treatment option with Atlantic Beach would be in their best interest.
I) The amount in dollars per thousand gallons to be charged by Atlantic Beach.
2) The required peak flow not to be exceeded by Neptune Beach.
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ADDITIONAL EVALUATION OF NEPTUNE WWTP INTERCONNECTION TO COAB WWTP -continued
.TUNE 6, 208
3) The surcharge amount (if any) for exceeding the peak flow limitation.
4) The updated average and peak flow estimates for the Atlantic Beach and
Buccaneer service areas.
This Supplemental Report (Memorandum format) will specifically address Item 2 and 4 above.
City of Atlantic Beach Wastewater Flows -Present & Projected
COAB Average Annual Daily WW Flows
Wastewater flows were evaluated based on population; percentage of potable water use and
actual wastewater flows. Wastewater flows have declined over the last few years and have been
attributed to conservation efforts, sewer rehabilitation and some temporary population reduction.
While both potable water and wastewater flows have declined over the last few years, there are a
number of redevelopment projects that are planned but are on hold due to the economy. The
redevelopment projects were well in the planning stage and a number of large tracts of existing
trailer parks and apartment buildings have been demolished in anticipation of the
redevelopments. Therefore a large percentage of the reduction in wastewater flows and
population was attributed to the demolition of these multi-family developments and relocation of
the population outside the wastewater service area of COAB.
Based on the our evaluation for wastewater flow projections, the use of the historical and current
wastewater flows were considered the most reliable method to use as a basis for establishing a
Year 2009 wastewater projection. Table 1 presents the wastewater flow rates (AADF) from both
the Atlantic Beach and Buccaneer Wastewater Service Area.
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JULY 13, 2009
ADDITIONAL EVALUATION OF NEPTUNE WWTP INTERCONNECTION TO COAB WWTP -continued
.TUNE 6, 2008
. •
'
ear ~
WWTP ~1 -
Annual Avg.
Flow
~Tl d ~ •
WWTP'#Z:
(Buccaneer) -
Annual Avg
Flow
an d ~ ~
_
Average Annual
Combined Flow
an d
1998 1.78 1.01 2.79
1999 1.53 0.95 2.48
2000 1.62 0.92 2.54
2001 1.56 0.88 2.44
2002 1.68 0.91 2.59
2003 1.74 0.84 2.58
2004 1.60 0.82 2.42
2005 1.82 0.75 2.56
2006 1.60 0.68 2.28
2007 1.64 0.71 2.35
2008 1.47 0.70 2.18
Average 2.47
The wastewater flow projections were developed fora 20 Year Planning Period that starts at the
end of 2009 and continues to Year 2030. The average year total from Table 1 of 2.47 MGD was
increased by a small wastewater flow increase of less than 1% per year. In addition, the flows
anticipated from re-development were phased in over a five year period beginning in Year 2012.
While the Mayport Navy Base may eventually be a home port for a new aircraft carrier that may
increase population and wastewater growth, no estimate is included in this analysis at this time.
In addition to the projection of wastewater flows for the Atlantic Beach, Table 2 presents Year
2009 through Year 2030 average day wastewater flow projections for both COAB and CONB.
The wastewater flows requested by the City of Neptune Beach of 0.550 MGD ADF is included.
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JULY 13, 2009
ADDITIONAL EVALUATION OF NEPTUNE WWTP INTERCONNECTION TO COAB W WTP -continued
.TUNE (,ZOOS
ear Projected Average
WW Flow - Atlantic
Beach/Buc Service
Area
m d l
Increase Due To
Known New.
Development-
an d
Neptune Beach
Average Day
Contribution
an d
Projected Total
Average Day WW
Flow -All Sources
an d
2009 2.49 0 2.49
2010 2.51 0.55 3.06
2011 2.53 0.55 3.08
2012 2.55 0.102 0.55 3.20
2013 2.67 0.102 0.55 3.33
2014 2.80 0.102 0.55 3.45
2015 2.92 0.102 0.55 3.58
2016 3.05 0.102 0.55 3.70
2017 3.18 0.55 3.73
2018 3.20 0.55 3.75
2019 3.23 0.55 3.78
2020 3.25 0.55 3.80
2021 3.28 0.55 3.83
2022 3.31 0.55 3.86
2023 3.33 0.55 3.88
2024 3.36 0.55 3.91
2025 3.39 0.55 3.94
2026 3.41 0.55 3.96
2027 3.44 0.55 3.99
2028 3.47 0.55 4.02
2029 3.50 0.55 4.05
2030 3.52 0.55 4.07
1. Based on it-year average of 2.47 mgd (per Table 1) and an annual increase of 0.8%.
COAB Maximum Day/Month/Peak WW Flows
Based on COAB historical wastewater flow data for both WWTP#1 and WWTP#2 (Buccaneer),
the following is provided:
Maximum Day = 3.97 MGD (May 2009)
Maximum Day Peaking Factor = l .92
Maximum Month Flow = 3.217 (1998); 3.166 MGD (2003) & 2.997 MGD (Highest Last 5
Years)
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ADDITIONAL EVALUATION OF NEPTUNE WWTP INTERCONNECTION TO COAB WWTP -continued
.TUNE 6, 20U8
Maximum Month Peaking Factor = 1.15 (Based on AADF of 2.791 MGD in 1998); 1.22 (Based
on AADF of 2.588 MGD in 2003) &1.17 (Based on AADF of 2.562 MGD in 2005)
No instantaneous peak flows have been recorded at the WWTP so the peak hour flow has not
been determined based on WWTP flow. In addition, the wastewater flow recorder at WWTP#1
will not measure flow above 3.0 MGD. During the excessive rain events of May 2009, the flow
meter pegged out at 3.0 MGD so it was actually unknown what flows where over a few days. A
new survey to obtain existing elevations at WWTP#1 is scheduled in the near future. This data
will be used to generate a hydraulic model of the existing WWTP#1 and will establish the peak
hydraulic capacity of the WWTP.
COAB -WWTP#1 Original Design Criteria -Review of ADF, Future Flow Projections &
Peak Hydraulic Capacity
A historical file review was conducted to determine the original hydraulic design of the
WWTP#1. Also afollow-up conversation was held with the original design engineer. Based on
historical reports and records and our conversation, the following design criteria was utilized in
the design of WWTP#1 in 1994-1995:
ADF Process Design = 3.0 MGD
Future ADF Process Design = 4.5 MGD (Required additional aeration basin and clarifier)
Hydraulic Design Basis = 4.5 MGD x Peaking Factor of 1.5 = 6.75 MGD
Therefore unless the new hydraulic model proves otherwise, the peak hydraulic capacity of
WWTP#1 is 6.75 MGD. While the intent of this report was to investigate peak flow conditions
that the existing COAB WWTP#1 can hydraulically manage without overflows, the detailed
hydraulic model supported by field surveys and measurements has not been completed. If the
model results show that there are areas of the WWTP that cannot accommodate peak flows at
6.75 MGD, then the WWTP will require upgrading of piping, structures, etc as required to meet
the 6.75 MGD or the peak flow hydraulic capacity of the WWTP will be reduced to actual model
results which may be below 6.75 MGD.
COAB -Evaluation of Wastewater Collection System Flows
To further investigate peak flow, a quick overview of the operating times for the major pumping
stations was analyzed during the excessive rainfall in May 2009.
COAB keeps detail records of pump run times on all city owned lift stations. Since all the pumps
in the collection system are constant-speed, the evaluation assumed that the total flows pumped
were proportional to pump run times. No attempt was made to evaluate actual flow rates -only a
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JULY 13, 2009
ADDITIONAL EVALUATION OF NEPTUNE WWTP INTERCONNECTION TO COAB W WTP -continued
JUNE 6, 2008
ratio of "Peak Flow: Average Flow" (actual flow rates could be based on actual WWTP#1 flow
data).
The evaluation only reviewed the pumping stations that pump directly to WWTP# 1. These
Pumping Stations include PS A, B, C, E, and F (Fleet Landing PS not included since it was
private).
The results of the study on the 5 pumping stations evaluated pumping or run time during
"normal" periods and "peak" periods. The average run time was 3.56 hours/day for the "normal"
periods. During the "peak" rain events in May 2009, the average run time was 12.18 hours. This
results in a "Peaking factor" of 12.18/3.14 = 3.42. The result of this analysis is included in the
Appendix.
While no inplant WWTP flow records were obtained during this study that effectively shows the
instantaneous peak hour flows, the peaking factor within the sewer collection system could be
higher than the 1.92 peaking factor shown at the wastewater treatment facility.
A preliminary hydraulic evaluation of the pumping stations within the two Atlantic Beach
Wastewater Service Areas was completed for this TM. The findings which are included in the
Appendix show that the peak pumping capacity of all lift stations is 4360 GPM which is 6.3
MGD which closely correlates with the maximum hydraulic capacity of the WWTP (6.75
MGD).
City of Neptune Beach Information Exchange on Wastewater Flows
CONB Average Day WW Flows
Average daily wastewater flows were provided by the City of Neptune Beach. The average
annual daily wastewater flows are listed for the same period as Table 1(Year 1998 through 2008)
as well as the average over the last three years is listed in Table 3.
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AGENDA ITEM # 9A
JULY 13, 2009
ADDITIONAL EVALUATION OF NEPTUNE W WTP INTERCONNECTION TO COAB W WTP -continued
JImrE 6, 2008
.•- '
Year • '~
COMB WWTP -Annual Avg.
Flow
m d
1998 0.996
1999 0.705
2000 0.647
2001 0.613
2002 0.747
2003 0.699
2004 0.571
2005 0.642
2006 0.493
2007 0.539
2008 0.535
11 YR AVERAGE 0.653
LAST 3 YR
AVERAGE 0.522
CONB Maximum Month/Peak WW Flows
In addition to the historical average annual daily flows provided by CONB, daily wastewater
flows were provided by CONB from January 2009 to Apri12009. The average daily flow for that
period was 0.494 MGD. The maximum day during the same period was 0.746 MGD.
From the flow data used to prepare Table 3 (1998 through 2008), the maximum month flow data
for Year 2006-2008 is as follows:
• October 2007 -1.429 MGD
• August 2008 - 0.994 MGD (Tropical Storm Faye)
• September 2008 - 0.819 MGD
Utilizing the CONB historical AADF of 0.539 MGD for 2007 and 0.535 MGD for 2008 from
Table 3, the associated maximum month peak factor would be:
• October 2007 - 1.429 MGD/0.539 MGD = 2.65
• August 2008 - 0.994 MGD/0.535 MGD = 1.86
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ADDITIONAL EVALUATION OF NEPTUNE WWTP INTERCONNECTION TO COAB WWTP -continued
.TUNE (, 2008
• September 2008 - 0.819 MGD/0.535 MGD = 1.53
In May 2009, both cities experienced excessive rain events where the wastewater treatment
facilities experienced high wastewater flows. On May 20, 2009, rainfall produced a recorded
peak flow of at least 2.4 MGD at the CONB WWTP, which was the maximum that could be
recorded. The reason that the flow measurement was maximized at 2.4 MGD at the CONB
WWTP was that the effluent weir was removed to prevent surcharging in the collection system.
Most of the flow into the WWTP is by gravity and if the weir was not removed overflows could
occur. If the ADF of 0.494 MGD (January 2009 to April 2009 ADF Average) was used as the
base flow, the peak hour flow factor would approximate 4.86 (2.4/0.494).
The duration of the peak rate of 2.4 MGD was not confirmed but flows continued high for a least
six days. On May 26, 2009, CONB recorded instantaneous hourly readings as follows:
Time Hourly Flow Peak Hour Factor
0900 1.267 MGD 2.56
1000 1.317 MGD 2.66
1100 1.326 MGD 2.68
1200 1.062 MGD 2.15
1300 1.370 MGD 2.77
1400 1.343 MGD 2.72
1500 1.329 MGD 2.69
1600 1.146 MGD 2.32
Based on the historical data provided by CONB, a summary of the peak flows, peak factor,
maximum day flows and maximum month flows would be as follows:
Peak Flow = 2.4 MGD on May 20, 2009 (maximum recordable)
Peak Hour Factor = 4.86 (May 20, 2009)
Maximum Day =Above 2.0 MGD (May 2009 -estimated for 2 days)
Maximum Day Peaking Factor = 4.05
Maximum Month Flow = 0.994 MGD (2008)
Maximum Month Peaking Factor = 1.86 (2008)
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JULY 13, 2009
ADDITIONAL EVALUATION OF NEPTUNE WWTPINTERCONNECTION TO COAB WWTP -continued
JUNE 6, 2008
Based on discussions with ATM, Neptune Beach would be committed to reducing their peak
hourly flow factor (PHFF) to the level that would normally be projected by using the formula in
the Ten States Standards document. For an AADF of 0.55 mgd this would equate to a PHFF of
3.15 and a peak hourly flow of 1.73 mgd. Higher short term peak flows would be attenuated to
this level through equalization provided in the digester (139,000 gallons) and possibly the
reaeration tank (125,000 gallons). Recent sewer rehabilitation efforts have reduced the peak
flows seen 18 months ago significantly however peak flows remain above the desired level.
The rainfall seen during the period between May 18 and 22, 2009 resulted in peak flows as high
as 2.4 mgd (PHFF 4.4) with an extended time (over two days) above the desired 1.7 mgd peak
flow. The proposed equalization tankage would be insufficient to attenuate peak flows of this
magnitude to the desired 1.7 mgd maximum. Neptune Beach has targeted the worst area for
infiltration (Bal Harbor) to be rehabilitated in the 2012 to 2013 timeframe. It is believed by NB
that by significantly eliminating the extraneous flow in this area, the PHFF would be reduced to
the desired range.
Summary, Conclusions & Recommendations
Summary
A summary of the flows from both COAB & CONB WWTPs is detailed in Table 4. The most
recent (Year 2008) average flow of the combined city's wastewater flows is 2.72 MGD. The
average over eleven years is 3.13 MGD.
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AGENDA ITEM # 9A
JULY 13, 2009
ADDITIONAL EVALUATION OF NEPTUNE WWTP INTERCONNECTION TO COAB WWTP -continued
JUNE 6, ZOOS
. • ~ ~
ear ~ ~ i i ~
COAB
Combined
WWTPs -
Annual Avg.
Flow
an d i ~ ~
~ .
COMB WWTP-
Annual Avg
Flow
an d ~ ~
Average
Annual
Combined
Flow
an d
1998 2.79 0.996 3.79
1999 2.48 0.705 3.19
2000 2.54 0.647 3.19
2001 2.44 0.613 3.05
2002 2.59 0.747 3.34
2003 2.58 0.699 3.28
2004 2.42 0.571 2.99
2005 2.56 0.642 3.20
2006 2.28 0.493 2.77
2007 2.35 0.539 2.89
2008 2.18 0.535 2.72
Average 3.13
From the standpoint of treatment capacity, the rerate of COAB WWTP#1 to 3.75 MGD would be
more than adequate to treat the combined wastewater (2.72 MGD - 2008 AADF) from the two
cities.
A comparison of the two cities maximum day wastewater flows, maximum month wastewater
flows and peak flows/peaking factors is shown in Table 5.
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ADDITIONAL EVALUATION OF NEPTUNE WWTP INTERCONNECTION TO COAB W WTP -continued
JUNE 6, 2008
. • ~ ~ ~ i i ~
Event i ~
COAB
Combined
WWTPs •
CONB WWTP
Combined
Flow
m d
Recent Maximum Da -MGD Ma 2009 * 3.79 2.000 5.79
Peakin Factor 1.92 4.05
Maximum Month -MGD Last 11 Years 3.22 1.429 4.65
Peakin Factor 1.15 2.650
Maximum Month -MGD Last 5 Years 3.00 0.994 3.99
Peakin Factor 1.17 1.860
Peak Hour Flow MGD ** 2.400 2.40
Peakin Factor *** 3.42 4.860
Note: * - 2 MGD is Estimate (CONB)
** - No Peak Hour Flow Recorded (COAB)
*** -Peaking Factor Is Based On Increased Pump Run Time (COAB)
Conclusions
In order to proceed to the next level of discussions between the City of Atlantic Beach and the
City of Neptune Beach, the following two questions have been evaluated and answered within
this memorandum. The questions and answers are summarized below:
1. The required peak flow not to be exceeded by Neptune Beach.
The best information to date on the peak hydraulic capacity of COAB's WWTP#1 is from
the historical records and discussion with the original design engineer. The original
design criteria for the peak hydraulic capacity of the WWTP#1 was 6.75 MGD. This peak
hydraulic flow will be confirmed in the near future with a new hydraulic model. Using
the 6.75 MGD as our guideline for peak hydraulic capacity, the following values are
assigned for peak hydraulic capacity for each of the cities:
COAB WWTP#1 is anticipated to be rerated for 3.75 MGD, so that the peak flow amount
that can be distributed between the two cities is:
CONB -Portion of 3.75 MGD Capacity = 0.55 MGD -Ratio Share = 14.67
CONB -Portion of 6.75 MGD Peak Capacity x 14.67 % = 0.99 MGD (say 1.0 MGD)
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JULY 13, 2009
ADDITIONAL EVALUATION OF NEPTUNE WWTP INTERCONNECTION TO COAB W WTP -continued
.TUNE (, 2008
COAB -Portion of 3.75 MGD Capacity = 3.20 MGD -Ratio Share = 85.33
COAB -Portion of 6.75 MGD Peak Capacity x 85.33% = 5.76 MGD
2. The updated average and peak flow estimates for the Atlantic Beach and Buccaneer
service areas.
Table 1 and 2 within this Memorandum provide the combined flows for the two COAB
wastewater service areas.
Recommendations
This Memorandum demonstrates the requirements for flow equalization above a peak hour ratio
of 1.81 (6.75 MGD Peak Hydraulic Capacity at COAB WWTP/3.75 MGD Rerated Treatment
Capacity at COAB WWTP) or approximately 1.0 MGD at the City of Neptune Beach WWTP. If
flow equalization is not implemented at CONB, then it will have to be implemented at COAB
WWTP#1. While the intent of the scope of this Memorandum was not to determine the actual
volume of flow equalization required at the CONB WWTP, it would be prudent for CONB to
prepare a hydrograph of their wastewater flow to determine the required equalization storage
needed.
While CONB anticipates a sewer rehabilitation program in the 2012 to 2013 timeframe, it does
not occur early enough to reduce the effects or impact of their wet weather sewer collection
system peaks to the COAB WWTP. In order to consider viable flow equalization solutions or
plans to properly manage peak flows until sewer rehabilitation can be implemented, the
estimated quantity of extraneous flows and the associated duration should be determined by
CONB. If little or no flow equalization is implemented at CONB, an immediate expansion at
WWTP# 1 (beyond 3.75 MGD) will be required for the years prior to a successful rehabilitation
program.
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JULY 13, 2009
ADDITIONAL EVALUATION OFNEPTUNE WWTPINTERCONNECTION TO COAB WWTP -continued
JUNE 6, 2008
APPENDIX
• May 2009 - COAB Pumping Station Run Time Evaluation
• Preliminary Hydraulic Evaluation of Pumping Stations
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Average of "Normal" times = 3.56
Average of "Peak" times = 12.18
Ratio Peak:Average = 3.42
AGENDA ITEM # 9A
JULY 13, 2009
June 30, 2009 7pm-8pm
Cars on grassed area of right-of-way or on the front yard
• Seminole Road south of Five Points -16
Ronal Palms
• Amberjack - 9
• Bonita - 2
• Cavalla - 4
• Cutlass -1
• Irex-4
• Mako - 9
• Sargo - 29
• Skate -11
• Redfin - 3
• Royal Palms -11
• Sabalo - 3
• Triton - 4
• Vecuna - 3
• Whiting -14
• Sailfish Drive, E. -10
• Sailfish Drive, W. - 24
Seasaray
• Belvedere -12