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PBSD Clam Bay Committee Agenda 10/27/2020 PELICAN BAY SERVICES DIVISION Municipal Service Taxing and Benefit Unit NOTICE OF PUBLIC MEETING OCTOBER 27, 2020 THE CLAM BAY COMMITTEE OF THE PELICAN BAY SERVICES DIVISION WILL MEET AT 1:30 PM ON TUESDAY, OCTOBER 27 AT THE COMMUNITY CENTER AT PELICAN BAY, 8960 HAMMOCK OAK DRIVE, NAPLES, FLORIDA 34108. AGENDA 1. Roll call 2. Agenda approval 3. Approval of 03/12/2020 meeting minutes 4. Audience comments 5. Clam Pass a. Station 14 tidal gauge repair update b. Clam Bay Management Plan Dredging Policy c. Tidal ratio data for 2016-2020 d. Bathymetric survey report May 2020 e. Aerial photos from 2017 and 2018 f. Timeline to dredge Clam Pass g. Intervention strategies 6. Water Quality a. 2019 annual WQ report b. 2020 WQ report for April, May & June c. Copper results 7. Clam Bay a. Update on spring and fall mangrove monitoring b. Update on hand-dug channel maintenance c. Canoe trail marker 6 signage d. Scaevola treatment proposal e. County boater safety signage 8. Dates for annual reports a. Clam Bay: December 18 b. Clam Pass Physical and Tidal monitoring: December 18 c. Water Quality: March 12, 2021 9. Next meeting 10. Adjournment ANY PERSON WISHING TO SPEAK ON AN AGENDA ITEM WILL RECEIVE UP TO THREE (3) MINUTES PER ITEM TO ADDRESS THE BOARD.THE BOARD WILL SOLICIT PUBLIC COMMENTS ON SUBJECTS NOT ON THIS AGENDA AND ANY PERSON WISHING TO SPEAK WILL RECEIVE UP TO THREE(3)MINUTES. THE BOARD ENCOURAGES YOU TO SUBMIT YOUR COMMENTS IN WRITING IN ADVANCE OF THE MEETING. ANY PERSON WHO DECIDES TO APPEAL A DECISION OF THIS BOARD WILL NEED A RECORD OF THE PROCEEDING PERTAINING THERETO,AND THEREFORE MAY NEED TO ENSURE THAT A VERBATIM RECORD IS MADE, WHICH INCLUDES THE TESTIMONY AND EVIDENCE UPON WHICH THE APPEAL IS TO BE BASED.IF YOU ARE A PERSON WITH A DISABILITY WHO NEEDS AN ACCOMMODATION IN ORDER TO PARTICIPATE IN THIS MEETING YOU ARE ENTITLED TO THE PROVISION OF CERTAIN ASSISTANCE. 10/21/2020 11:26 AM PELICAN BAY SERVICES DIVISION CLAM BAY COMMITTEE MEETING MARCH 12,2020 The Clam Bay Committee of the Pelican Bay Services Division met on Thursday, March 12 at 1:30 p.m. at the SunTrust Bank Building, 801 Laurel Oak Drive, Suite 302,Naples,Florida 34108. In attendance were: Clam Bay Committee Denise McLaughlin Susan O'Brien, Chairman Rick Swider Pelican Bay Services Division Staff Sarah Hamilton, Operations Analyst (absent, Neil Dorrill, Administrator (absent) Lisa Jacob, Project Manager Chad Coleman, Operations Manager Barbara Shea, Admin. Assistant (absent) Also Present Mohamed Dabees, Humiston& Moore Jeremy Sterk, Earth Tech Tim Hall, Turrell, Hall & Associates Dave Tomasko, Environ. Science Assoc. APPROVED AGENDA (AS AMENDED) 1. Roll call 2. Agenda approval 3. Approval of 01/09/2020 meeting minutes 4. Audience comments 5. Water Quality a. Copper results b. Second and third water quality report c. 2019 Annual Water Quality Report d. Water Quality Report (add-on) 6. Clam Pass a. February tidal ratio report b. Video of H&M report c. Timeline for dredging-related activities d. Bathymetric survey (add-on) 7. Clam Bay a. Update on monitoring b. Hand-dug channel maintenance c. Canoe trail marker 6 signage d. Scaevola treatment proposal e. Update on County boater safety signage 8. Beach Renourishment a. County Survey Results b. Update on County Beach Resiliency program 9. Draft of FY2021 Clam Bay Budget 1 Pelican Bay Services Division Clam Bay Committee Meeting March 12, 2020 9.5. Ms. McLaughlin's Beach Renourishment article (add-on) 10. Next meeting: May 12 or 14, 2020 11. Adjournment ROLL CALL All members were present and a quorum was established AGENDA APPROVAL Items #5D, #6D, and#9.5 were added to the agenda. APPROVAL OF 01/09/2020 MEETING MINUTES Ms. McLaughlin motioned, Ms. O'Brien seconded to approve the 01/09/2020 meeting minutes as presented. The motion carried unanimously. AUDIENCE COMMENTS None WATER QUALITY COPPER RESULTS Ms. O'Brien commented that we are seeing steady improvement in our Clam Bay copper results (the copper table was included in the agenda packet). SECOND AND THIRD WATER QUALITY REPORT Ms. O'Brien commented that the major takeaway from the second and third quarter water quality report is the high level of phosphorus in Clam Bay. 2019 ANNUAL WATER QUALITY REPORT After committee discussion, Dr. Tomasko, consultant with Environmental Science Associates, agreed that his 2019 Annual Water Quality Report (that he is working on) would include all of the 2019 calendar months plus the last three months of 2018. CLAM BAY PHOSPHORUS LEVELS Ms. O'Brien commented on the recent history of phosphorus levels in Clam Bay including (1) in 2016, phosphorus levels were not a problem, (2) in 2017, phosphorus levels were a little bit worse, and (3) in 2018 and 2019, phosphorus levels have continued to increase. Dr. Tomasko commented that higher levels of phosphorus in 2017 were a result of Hurricane Irma. He explained that a high level of phosphorus is not necessarily dangerous if it is not causing a related chlorophyll problem or water clarity problem. Dr. Tomasko suggested further analysis to determine whether our chlorophyll and/or water clarity are being affected by the phosphorus levels. His first focus will be to look at the data from berm stations and then each specific Clam Bay station. Dr. Tomasko emphasized that we need to determine whether our high phosphorus levels are really a problem. He will provide his report to the committee in 30-60 days. Dr. Dabees, consultant with Humiston & Moore, commented that Outer Clam Bay is a completely different system from Inner Clam Bay as they each have very different flushing timelines. Dr. Tomasko noted that the two key factors to maintaining good water quality in Clam Bay are (1) keep tannin levels high, by maintaining trees and vegetation around our lakes, and (2) 2 Pelican Bay Services Division Clam Bay Committee Meeting March 12,2020 keep Clam Pass open. Dr. Tomasko commented that the main problem with a process to remove phosphorous from County reclaimed water,is the disposal of the phosphorus waste. He also noted that in the State of Florida all bodies of water must be monitored. Dr. Tomasko commented that Florida DEP does not see the water quality along the Southwest Coast of Florida as problematic. CLAM PASS FEBRUARY TIDAL RATIO REPORT The February tidal ratio report was included in the agenda packet. VIDEO OF H&M REPORT Not discussed TIMELINE FOR DREDGING-RELATED ACTIVITIES A flowchart of the timeline for a project to dredge Clam Pass was included in the agenda packet. Dr. Dabees suggested that it may be beneficial for the PBSD to have funding available for quick mechanical interventions (lasting a few days) to make minor corrections to the inlet, which would enable the system to recover quickly from weather events. The ability to make quick interventions may eliminate or delay a potential full dredge project. Ms. O'Brien suggested that we may see pushback from the community if we use our own funds for dredging activities, instead of requesting funding from the TDC. She also suggested that small interventions are not included in the Clam Bay Management Plan. Dr. Dabees commented that quick interventions are included in our permitted activities. Mr. Swider suggested that the Budget Committee would be able to set up a reserve of $25,000 for these types of interventions (if the board agreed). The committee agreed that this suggestion should be explored further. BATHYMETRIC SURVEY (ADD-ON) Dr. Dabees commented that a bathymetric survey of the Clam Pass inlet will be done in May, and will provide information on our metrics which will allow us to determine whether there is a need for pre-emptive maintenence. If necessary, a maintenance project would be completed between November and April, which would have no adverse effects on sea turtle nesting season. Dr. Dabees commented that in the past, the TDC (Tourist Development Council) has always approved funding for our dredging projects. CLAM BAY UPDATE ON MONITORING AND HAND-DUG CHANNEL MAINTENANCE Mr. Sterk, consultant with Earth Tech, commented that Earth Tech will begin mangrove monitoring work next week. This work will include an evaluation to determine what areas to focus on for hand-dug channel maintenance. CANOE TRAIL MARKER 6 SIGNAGE Mr. Sterk commented that he will follow up with County personnel on the repair of Marker #6 signage. SCAEVOLA TREATMENT PROPOSAL Ms. O'Brien suggested that we need a ballpark opinion of cost for a scaevola removal project, so that we can put in a request to the Budget Committee for FY2021 funding. Mr. Sterk 3 Pelican Bay Services Division Clam Bay Committee Meeting March 12, 2020 commented that he will work with Ms. Jacob to calculate an opinion of cost within 30 days. He noted that Earth Tech has already mapped the scaevola throughout Pelican Bay. Mr. Sterk commented that the County Coastal Zone Management Division has discussed a possible county- wide scaevola treatment project. He noted that if left untreated, the scaevola will begin to impact the gopher tortoise habitat and the beach dune habitat. UPDATE ON COUNTY BOATER SAFETY SIGNAGE Ms. Jacob commented that she has no new updates on the County boater safety signage. Mr. Tim Hall, consultant with Turrell, Hall & Assoc., does not expect the County to address this issue until after three County dredging projects are completed. BEACH RENOURISHMENT COUNTY SURVEY RESULTS Ms. O'Brien expects that the committee will have the County's beach width survey results to review at our May committee meeting. UPDATE ON COUNTY BEACH RESILIENCY PROGRAM Ms. O'Brien is hopeful that a representative from the County's Coastal Zone Management Division will provide an update on the County's proposed resiliency program at our May committee meeting. DRAFT OF FY2021 CLAM BAY BUDGET Ms. O'Brien included a draft of the FY2021 Clam Bay budget in the agenda packet; the budget is very similar to the FY2020 budget. MS. MCLAUGHLIN'S BEACH RENOURISHMENT ARTICLE (ADD-ON) Ms. McLaughlin provided a draft of her article on beach renourishment to the committee (to be included in a future PB Post edition), and requested clarification on whether we would ever take on a beach renourishment project on our own. Mr. Hall commented that if we were to renourish an area of PB beach on our own,that the sand would migrate over time to other beaches, and therefore, would not be effective. He suggested that the PBSD might consider its own beach renourishment project, only in the event of structures being jeopardized from short beach widths. Ms. O'Brien suggested that we could only consider a small PB beach renourishment project if our beaches were critically eroded. After discussion, Ms. McLaughlin summarized (for the article) that a small PB beach renourishment project would not be effective unless the entire stretch of beach was included in a larger beach renourishment project. NEXT MEETING: By consensus,the committee agreed that the next meeting of the committee would be held on May 14, 2020 at 1:30 p.m. ADJOURNMENT The meeting was adjourned at 2:46 p.m. I 4 Pelican Bay Services Division Clam Bay Committee Meeting March 12, 2020 Susan O'Brien, Chairman Minutes approved { 1 as presented OR I 1 as amended ON F 1 date 5 Agenda item#5b Page 1 of 4 CLAM BA YNRPA MANAGEMENT PLAN Pelican Bay Services Division October 2014 Ver. 6.5 5.0 Clam Pass Dredging A. Dredging Policy There are two circumstances that could necessitate dredging Clam Pass. 1. Clam Pass closes or is in imminent danger of closure following a weather driven event. In this situation the inlet should be dredged as soon as possible. 2. The inlet has lost hydraulic efficiency and is jeopardizing the long-term health of floral and faunal communities of the Clam Bay NRPA. The scope and timing of any proposed dredging activity will be determined by reviewing and comparing current and past hydraulic, bathymetric and ecological monitoring data. In both cases the PBSD Board would,after consultation with and advice from qualified coastal engineers and biologists,approve and recommend an appropriate set of construction drawings for the dredging event to the BCC for its approval prior to the submittal to the regulatory agencies. Dredging will only be done for the health of the Clam Bay NRPA,not for navigation or beach renourishment. Beach-compatible sand removed as part of the dredging event will be spread on adjacent area beaches,as required by the permitting agencies. B. Hydraulic and Bathymetric Dredging Criteria The purpose of regular hydraulic and physical monitoring is to evaluate inlet characteristics on a comprehensive long term basis with less emphasis on short term or seasonal changes. To monitor the stability of Clam Pass,data on the variables listed below will be regularly collected and reviewed by qualified engineers. If data are not within the identified target ranges for the variables, further monitoring and/or intervention will be considered in conjunction with current ecological data. See Appendix 5 for additional information on the dredging criteria. 1. Bay Tide Range Tidal range data have been collected annually since 1999 and will continue to be collected and reported to the consulting engineer at least quarterly. An annual tidal analysis report will be included with the annual report. Data are collected from gauges at four locations(Clam Pass Park Boardwalk, Pelican Bay South Boardwalk,Pelican Bay North Boardwalk,and Upper Clam Bay). These gauges provide a record of the tidal range within Clam Bay and are one indication of the tidal prism or volume of water flowing through Clam Pass at each tidal cycle. 43 Agenda item#5b Page 2 of 4 CLAM BA YNRPA MANAGEMENT PLAN Pelican Bay Services Division October 2014 Ver.6.5 Based on an analysis of data from the gauges at the South Boardwalk and Clam Pass Park Boardwalk from 1998 to the present when the inlet was hydraulically stable,the ratio between Clam Bay and Gulf tide was between 0.6 and 0.7 over 90%of the time. Therefore, if the ratio between Clam Bay and the Gulf tide falls below 0.6,but above 0.5, further monitoring will be considered once it has been established that other types of blockage are not causing the problem. If the tidal range ratio falls below 0.5,physical monitoring of,or interventions to,potential shoaling areas that could be impeding flow will be considered. 2. Cross Section of Flow Area and Volume of Shoaled Material Annual bathymetric surveys and reports were completed from 1999 to 2008. Bathymetric surveys provide data on the physical conditions of the inlet channel,ebb shoal and flood shoal. Post-dredging bathymetric surveys and reports were completed at 3-month,6-month,and I2-month intervals following the opening of Clam Pass in April 2013. Beginning in 2014, bathymetric surveys and reports will be issued at least annually. Additional surveys will be considered if the hydraulic efficiency falls below target levels. To establish benchmarks or targets for flow area and volume of shoaled materials,the data analysis included evaluation of the flow cross-section areas in the three main sections of the dredging region. Section A represents the inlet channel, Section B the seaward part of the flood shoal, and Section C the bay side part of the flood shoal. Section C `1 • • • 1+1 Section A ,q 44- Vim:. ._ Figure 20:Sections A,B and C of Clam Pass The analysis included evaluation of the cross-section of flow between mean high water and the volume of sand within each segment. The cross-section of flow was computed at each survey station spaced approximately 50 feet apart. The average and minimum cross-section areas were used as indicators of 44 Agenda item#5b Page 3 of 4 CLAM BA Y1VRPA MANAGEMENT PLAN Pelican Bay Services Division October 2014 Ver. 6.5 the physical condition of the flow area of the three segments. The cross-sections were compared to the design cross-section area of the 2013 dredging and the inlet conditions in 2004 and 2008 when inlet conditions were near equilibrium 24 months and 16 months,respectively,following dredging events. Targets for the average cross-section of flow areas below MHW: Section A greater than 300 sq. ft. Section B greater than 450 sq.ft. Section C greater than 450 sq. ft. Targets for the minimum cross-section of flow areas below MHW: Section A greater than 250 sq. ft. Section B greater than 350 sq.ft. Section C greater than 350 sq. ft. Targets for volume of shoaled materials: Section A less than 3000 cu.yds. Section B less than 2500 cu.yds. Section C less than 4000 cu.yds. Therefore,if the average cross-section of flow area falls below these numbers or the volume of shoaled material exceeds these numbers, further monitoring or intervention may be needed. 3. Inlet Channel Length The channel length is an important factor in inlet stability. A longer inlet channel will provide greater resistance to flow. Higher flow resistance will reduce the tidal range and increase the phase lag with the Gulf tide that reduces the tidal prism and flow through Clam Pass. To establish a benchmark for channel length a selection of aerial photos of Clam Pass from 2004 to 2013 was studied as well as data on the approximate length of the channel following dredging events in 2002,2007,and 2013. Based on this analysis,the benchmark for inlet channel is to stay under 400 feet in length. Inlet channel length will be recorded at least annually and included in the annual report. 4. Ebb Shoal The size and shape of the ebb shoal is a key factor to the stability of the inlet that, in turn,supports the stability of Clam Pass. The ebb shoal helps to keep the inlet open when facing storms and big wave events. The ebb shoal provides sheltering to the channel and a sand bypass pathway around the inlet without filling in the Pass. The shape and volume of the ebb shoal are additional indicators of the stability of the inlet. Critical conditions include onshore collapse of the ebb shoal that can be indicated by significant change in ebb shoal offshore distance,volume,and increase in dry beach areas adjacent to the inlet. 45 Agenda item#5b Page 4 of 4 CLAM BA YNRPA MANAGEMENT PLAN Pelican Bay Services Division October 2014 Ver. 6.5 To determine a target for the ebb shoal delta,data from April 2013 to April 2014 were reviewed. The ebb shoal position offshore is measured from a line connecting the north and south channel banks at mean high water out to the-4.0 foot contour line. The recommended length of the seaward extent of the ebb shoal is at least than 250 feet. The ebb shoal distance from shore will be recorded at least annually and included in the annual report. A summary of criteria for dredging is presented in the table below. Dredging Criteria Parameter Summary Location Target Description >0.6 ratio comparison of the interior and Gulf Bay Tide Range Ratio tidal ranges A Average>300 sq ft Not less than 250 sq ft Cross Sectional Area B Average>450 sq ft area in different locations of the Pass Not less than 350 sq ft through which water can flow C Average>450 sq ft Not less than 350 sq ft A <3000 cu yds quantity of sand and sediments within Volume of Shoaled Material B <2500 cu yds channel that can restrict flow C <4000 cu yds Inlet Channel Length <400 feet distance water must flow through the beach and ebb shoal areas Ebb Shoal >250 feet distance from shore to the outer ebb shoal limits C. Ecological Considerations A critical consideration in all dredging decisions is to ensure the ecological health of the Clam Bay NRPA. Before any dredging event,the direct and indirect impacts on the flora and fauna of the NRPA including mangroves, benthic communities(including seagrass),and other important species, such as fish and birds,will be considered. Every effort will be made to minimize any negative impact to the flora and fauna. The pros and cons of dredging will be weighed in regards to both hydrologic and ecological consequences. D. Dredging Construction 1. Typical Cross-Sections for Dredging Typical cross-sections for the suggested dredge design are provided below. When dredging is deemed necessary,the design cross-section area as stated in the design range,with consideration to existing conditions,will be followed. Minor modifications to this dredging template may be needed for future permitting. Typical cross-sections are shown for open areas in Sections B and C where the waterway 46 10/20/2020 ClamPass-TIDE I humistonandmoore Agenda item#5c Page 1 of 2 ' Restoring eeacies as Alatura( Coastal „5.isferizs ' HUMISTON & MOORE Iii-i.4----11 CNGINEERS Consulting Coastal Engineers Home About H&M Services Projects Contact Careers Client Login ci. CLam Pass Tide Monitoring - Click here for Maintenance Dredging Project details Gar/o/Mexico �'`� MARKER 4 MARKER 14 MARKER 26 MARKER 32 Uvm Foss h y r . •' \\ 1 - . er r � n� y ;ti. •. y i t ..'. �:.:-re:' - :s J , r'� G, . �;:: sp •. ,Pfi : A ,r .1,3 ` .JP . ga I Tide Gages Location Monthly Time Series 2020(Click on Thumbnails to Expand) '' Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec •'•4Yv. Mean Low TideTime Lag -2020 ?0o.0 - Pass 250.0 • Maintenance 7 ■Marker 4 a i 200.0 - v l I !Marker 14 •Marker 26 2 Marker 32 1500 - I I1:: : I . II I• • I working 0.0 , I properly Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Gage/Gulf Mean Tide Ratios -2020 u,tlu ^ Pass 0.80 Maintenance *Marker 4 0.70 r:Ma rke r 14 p 0.60 A --r 1 II Marker 26 ;� {+ i V l� t! _� s I 4 ix Marker 32 d 0.50 ro `Gar not ~ 0.40- c working 2ro 0.30- I 11 Properly ill I 1 Cynical 0.20- i rI ,... I ---- suaairy Asia 0.10 - t r III !Unpile • • • a, R'•Aerr 0.00 r r r r r r , I , r r • 41.13. Jan Feb Mar Aar May Jun Jul Aue Ste Oct Nov 0cc Gage/Gulf Mean Tide Ratios -2019 https://www.humistonandmoore.com/clampass-tide 1/3 10/20/2020 ClamPass-TIDE I humistonandmoore Agenda item#5c Page 2 of 2 " Afestorirlo jeaches as AIaturar( eoc:stal „cc�sterns " r HUMISTON & MOORE ENGINEERS Home About H&M Services Projects Contact Careers ClientLo in 1.11 Consulting Coastal Engineers9 Q+o..ro 0.40 ' ' I I I I I i I I I U I 1 r Marker 26 Gage/Gulf Mean Tide Ratios -2018 0,90 - PASS out>utra - 0.80 - r •flop not 0.70 . 1 I I I erorkiug i Pr()poly a 0.50 ! ■Marker 4 t ........... ... ~0.40 la Marker 2G 0.30 n Marker 32 E lI i IF • Amp re• . &WWI Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec as 1u. Gage/Gulf Mean Tide Ratios -2017 0.9 MUM! IIynlc4ne+'m• 0.8 TWD<S sfom E•n4 0.7 s 0.6 IJik ra it.,_� , II a►p tan Feb Mar Apr May Ion Jul Aug Sep Oct Nov Dec J&14. Gage/Gulf Mean Tide Ratios -2016 0,9 PASS T.S. 0.8 DRrociax, T.S.ColtN NtAMINt 0.7 y y - S 0.6 a r Marker ej 0,5 rt Marker 1 c 0.4 a Market 2G 4' 0.3 n Marker 32 0.2 , CnlKal Ian Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec a&to. Definitions: Mean Tide Ratio:ratio of tide amplitude of gages over the tide amplitude from the Gulf of Mexico,averaged over a month.This ratio is representative of the pass's effectiveness in flushing water from the bay. The lower the ratio, the less efficient is flushing,indicating material accumualting in the pass. Mean Low Tide Lag: time difference between low tide in the Gulf of Mexico and at the gage's locations, averaged over a month in minutes.The time lag is also represenattive of the pass's effectiveness in flushing water from the bay.The higher the lag the less efficient is flushing,indicating material accumulating in the pass. https://www.hurnistonandmoore.com/clampass-tide 2/3 2019 Clam Pass Management Review Pelican Bay Services Division Agenda item#5d Page 1 of 1 3. Inlet Dredging Cost Analysis As discussed above,Clam Pass is a small inlet and requires maintenance dredging to maintain the health of the Clam Bay ecosystem and avoid potential for inlet closure.The inlet has been dredged a total of 7 times since the development of the initial NRPA management plan in 1998.The dredging template and methods of dredging varied depending on conditions and timing of each event. Table 2 provides listing of dredging information and costs for each of the 7 events.The record indicates that 5 dredge events used hydraulic dredging equipment which enables dredging the entire dredging template including the interior flood shoal areas. Two events in 2013 and 2017 were limited to mechanical excavation equipment which included partial dredging of the template limited to the inlet channel and small part of section B of the flood shoal area. The limited excavation by mechanical equipment provided cost effective and rapid response to emergency conditions following inlet closure in 2012 and to avoid inlet closure in 2017. Table 2 Details of dredging events information and costs for Clam Pass Pay Quantity VTotalolume SectionA Dredge IConstruction equivalent r Year Equipment Construction Cost , (rndudesgrading)(includes Dredge Cost(2028$) i grading) Width Depth 4 based on bid tabulation (cY) fry) (feet) (feet) A -5.0 NGVD • 1999 I B 32,000 -4.0 NGVD 30 Hydraulic $ 321,030 $ 484,755 C -4.0 NGVD I I A ND 2002 B 11,725 -4.0 NGVD Hydraulic { $ 162,125 $ 230,218 1 l i C ND A -5.5 NGVD 2007 B 20,603 80 -4.5 NGVD Hydraulic $ 376,417 J $ 455,465 C -4.5 NGVD ? } 2012 filet Closes A 13,00S -5.S NAVD 2013 I 20,266 45 Mechanical a 4,824 -5.3 NAVD Mechanical 233,411 $ 252,084 C 2,434 -5.3 NAVD A 9,366 -5.0 NAVD 2016 B 3,368 18,987 50 -4.0 NAVD Hydraulic i $ 469,000 ly $ 492,450 C 6,253 -4.0 MAVO A 10,994 -5.0 NAVD $ 85,303 2017 10,994 50 Mechanical B ND -4.0 NAVD I $ 82,818 C ND -4.0 NAVD I i A 6,275 -5.0 NAVD 2015 B 3,320 11,685 50 -4.0 NAVD Hydraulic $ 235,982 $ 235,982 C 2,090 -4.0 NAVD 'ND indicates no dredging occurred in this section. As discussed in previous sections of this study, the inlet is critically stable under typical conditions and excessive shoaling is directly related to sequence and intensity of storms. The average interval between dredging events is 3 years.The largest interval between dredging events was 6 years between 2007 and 2013 which included inlet closure in 2012. Annualized cost over various time frames are shown in Figure 15. . 0°;20 ....."- '1 c,---d pvt g--til-T-e /)---1-,N4,-21j ay./ -7J 12 6 aii3 C 3139 T,.4- 1 6 5 s'"b Agenda item#6c Page 1 of 1 Clam Bay Copper ug/L Collection Date CB1 CB2 CB3 CB4 CB5 CB6 CB7 CB8 CB9 Report Date 6/22/2016 0.862 0.700 0.700 0.700 1.640 2.100 0.700 3.520 1.510 9/8/2016 7/20/2016 0.924 5.330 5.110 5.660 2.470 3.960 4.950 5.710 10.500 9/12/2016 7/20/2016 0.924 6.160 4.700 1.690 2.470 1.830 1.980 1.870 8.360 9/21/2016 8/25/2016 2.000 1.850 1.680 1.470 1.240 1.520 2.250 1.280 8.060 10/4/2016 9/20/2016 1.690 2.280 1.280 1.760 0.751 0.700 0.700 1.030 0.700 11/22/2016 10/12/2016 2.760 2.200 2.130 1.190 2.900 1.860 1.060 0.954 1.310 12/7/2016 11/9/2016 2.340 3.390 2.300 2.250 1.630 1.500 1.180 2.030 1.300 1/16/2017 12/6/2016 2.330 2.930 5.100 2.450 2.390 1.780 1.270 1.880 1.720 3/14/2017 1/19/2017 2.570 3.560 2.110 1.990 0.818 0.800 0.961 1.110 2.020 4/4/2017 2/23/2017 2.510 3.350 1.600 1.120 0.851 0.848 1.500 2.570 2.600 4/24/2017 3/21/2017 7.970 4.080 1.710 1.120 0.894 0.846 1.080 1.090 0.957 6/1/2017 4/18/2017 6.480 8.160 1.620 1.240 0.800 0.956 1.280 1.010 1.100 6/14/2017 5/24/2017 2.840 4.060 4.990 0.800 0.800 0.959 0.800 0.920 0.946 7/6/2017 6/21/2017 3.840 4.240 3.850 0.906 1.200 1.140 1.260 1.110 0.760 8/8/2017 7/13/2017 4.700 2.950 3.800 4.080 2.500 2.440 2.370 2.380 2.210 8/29/2017 8/14/2017 4.290 3.810 3.220 2.650 1.400 1.220 1.470 1.020 0.700 10/10/2017 10/4/2017 2.680 1.270 0.600 0.800 12.600 1.610 0.600 0.600 1/22/2018 11/28/2017 0.700 0.722 2.540 0.700 0.700 0.700 0.700 0.700 0.700 1/22/2018 12/12/2017 1.780 2.250 1.890 0.700 1.210 1.210 1.300 0.728 0.911 3/26/2018 1/8/2018 0.420 1.510 1.690 1.590 0.800 0.809 0.800 0.800 2.400 4/27/2018 2/6/2018 3.400 3.980 2.130 2.420 0.829 1.640 3.920 0.800 0.800 4/30/2018 3/22/2018 5.450 4.890 3.670 2.370 1.010 1.040 1.750 1.010 1.320 5/11/2018 4/4/2018 2.370 3.190 2.380 1.970 1.690 0.848 1.280 1.250 5.160 6/11/2018 5/8/2018 5.490 4.880 2.360 1.090 0.800 1.050 1.270 1.570 1.640 7/2/2018 6/6/2018 3.120 3.320 2.670 0.800 0.800 0.853 0.828 1.080 1.220 7/18/2018 7/17/2018 1.400 1.440 1.600 1.600 2.270 1.600 1.600 1.600 1.600 8/21/2018 8/15/2018 1.500 1.410 1.400 1.400 1.600 1.600 1.600 1.650 1.600 10/8/2018 9/13/2018 1.720 1.960 1.200 1.200 1.400 1.400 1.400 1.600 1.400 10/9/2018 10/15/2018 3.190 4.800 4.400 4.030 1.400 1.400 1.960 1.400 1.400 12/21/2018 11/14/2018 1.750 1.900 1.960 1.600 1.600 1.600 1.600 1.600 1.600 2/28/2019 12/12/2018 4.480 2.790 2.400 1.820 1.600 1.600 1.600 1.600 1.600 2/28/2019 1/14/2019 3.150 2.740 2.100 1.880 1.600 1.600 1.600 1.600 1.600 5/3/2019 2/25/2019 3.420 2.470 2.000 1.940 1.600 1.600 1.600 1.600 1.600 5/3/2019 3/25/2019 1.830 3.090 1.600 2.730 1.600 1.600 1.600 1.600 1.600 5/14/2019 4/11/2019 2.310 2.530 1.720 1.910 1.600 1.600 1.600 1.600 1.600 8/8/2019 5/9/2019 2.290 3.160 2.030 2.720 1.600 1.600 1.600 1.600 1.600 8/8/2019 6/25/2019 3.030 2.460 1.720 1.600 1.600 1.600 1.600 1.400 1.450 8/8/2019 7/24/2019 2.660 2.020 1.770 1.600 1.400 1.400 1.400 1.400 1.660 10/1/2019 8/8/2019 2.760 1.710 2.100 2.090 1.400 1.400 1.400 1.400 1.400 10/1/2019 9/5/2019 2.030 1.410 1.400 1.400 1.400 1.400 1.400 1.400 1.400 10/1/2019 10/21/2019 1.870 2.120 1.950 1.450 1.430 1.600 1.600 1.600 1.600 1/13/2020 11/19/2019 1.400 1.600 1.600 1.600 1.600 1.600 1.600 1.600 1.600 1/13/2020 12/16/2019 3.030 3.940 2.310 1.810 1.600 1.600 1.600 1.600 1.600 1/13/2020 1/16/2020 5.090 2.710 2.000 1.670 1.600 1.600 1.600 1.600 1.600 4/14/2020 2/12/2020 2.430 3.580 4.270 2.160 1.600 1.600 2.690 1.600 1.600 4/14/2020 3/2/2020 3.170 4.260 2.080 1.600 1.600 1.600 2.870 1.600 0.200 4/14/2020 4/22/2020 3.040 2.090 1.700 2.000 1.200 1.200 1.450 1.210 1.200 7/29/2020 5/28/2020 2.530 1.870 1.410 1.590 1.200 1.200 1.200 1.200 1.200 7/29/2020 6/11/2020 2.640 2.640 2.140 2.350 1.050 1.050 1.050 1.050 1.050 7/29/2020 7/27/2020 3.220 2.290 1.410 1.200 1.200 1.200 1.200 1.200 1.200 10/12/2020 8/26/2020 1.350 1.840 1.200 1.200 1.200 1.200 1.270 1.200 1.200 10/12/2020 9/8/2020 2.010 2.080 1.910 1.630 1.200 2.000 1.310 1.200 1.500 10/12/2020 Agenda item#5e Page 1 of 2 +•' .. • _ .lya-'nF ` fst y- �'"',, ., _ c^"i'!% ♦ may.z. .y M tl. 1�iM*lI(�•C�:' . .fir. i s. < y .. .,„ , - '`' P'S 4.., ..,. ..... , , . . .. ..... ... .�'ye '• - ,� • , ,___ , .. ...,........,,,_,"..:.<•fir . . - t'``.: . ,,.. . �\ L4 ........,_ ' R • _ .... _ ,__, . 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'4,..4...,(,,i'''.'.,'..,.14 .'---••' '...:4..*:',. • ,.,•,!':' 5 !:•'„0".,S,*1-g,'•- .', . . .,. .).. A- D *."...1,'! .. 4 -...4. t'etil'I ' ' - .e.',, W;,,:. .it .4•, - 1,, * 4 , .• .'',44.ki ;, k, •••- .-,4. ,,,...4t. ..i .0...,::. .4-45.17*,ii.,,,,4-.4,-li•Ni...t. 4,5 ,,. • .. , •„ 4 ' • .A ..4.• ,-, ' .;Si--i,. I-. ,ft,:i! . - - . 4, 4.: • 8:8‘,-,.....„1,,- 1 .. • , S ,.‘„.,, 00;I: '' 8-•Ww .4 • , ' .1,-, .',44,-,. • 4 IP ' : i;. 1...- ..., i 1. I'v,,..--,. .\,. • i .,. Itii , t i,1/4" it- ..,, 1 f';-* .• ..-„,...,i ,i-•,1 \ ,""i : , " kii . . ... . 'if. .... ".. , • i, . A .., im.: .) -Iii. • • iiti,:i-.....,;V;'--- . 1•.i4f1A1 t. „, • , , : ...„- ,, • ty. . . .3..,,,,,,„..',.. -,,',‘•-_,.r.„,_-...,,.,:.,,,..::..1;;.-,-.-:,-,....-,...:.: ••., , ,.:::„...,..,,,f.„... ...:-:---„,,,,,,.,•:„.• , , .,. ., to 4 . %.,, .. ' .,,,Ipit,;/':,.'4.--"• ..'' . . 4 •:.;"i'--4,'-'','`4..A4.4'F;-"rf!J:e*,','.„'''1t-p.;..4,;.;;:..=:;-.I 4'r1,.,13*--•4',1;1,e::,1-,:r,:s-•..--•'A.',`:'.-:',r,-.t,f.-':t.-'.''..":.-1;':;^-" ; :.?A'"7-,..•::7.,- .' " ' •te-..4-: ' •4 .•.'.:1 4-: It .t•,. • .-..;...v-.44%.".:::t. ."A.I.,-ww,„.....,45',,,L.,•- . • • �_ _.. Agenda item#5f Page 1 of 1 r) O Q m i ° -0 D n z o n O CO n 0 �; Et N n Q r) o D Qo c D °- z 0 (o o0 � mo CL g O V1 0 a a n v 2 m .. 3 Co O Cry o TD 0 cn N Q II N C (D C r-h Q el. 0 N• < < (D Q C W O m On (D cn. (D (D ! o [ r+ -0 _ (D -h Q) a. I O -• - Gl V1 .< O .- ,a, _ _- r Zr.,. rt O O n n) 1(D n -f; ., m n -aorq C n rD N 0 o CM Q90 z '{ o D � c^ p -0 Ort Q 713 n (D v, o O 0 o N O c m co7 0 io __. n N rt• -t �, n (D • N rt CU O Qp rt r�-I. O n (D p 01 al O O r+ et, l0 to n n 0 o (D (D Ot`. -o 0 n = .__----. ._._.._ n. D rf 1-I- rf al D o � 0) o C -0 Q n V1 (D Agenda item#6a Page 1 of 5 4350 West Cypress Street www esassoc con Suite 950 Tampa,FL 33607 813.207.7200 phone 813.207.7201 fax memorandum date April 29.2020 to Tim Hall 'l urrell, Hall and Associates, Inc. from David Tomasko,Ph.D. Emily Keenan,M.S. subject Annual Report on Clam Bay Numeric Nutrient Concentration(NNC)Criteria Executive Summary Water quality data collected from Clam Bay between January 2019 and December 2019 were analyzed to determine the degree to which the waters of Upper, Inner and Outer Clam Bay are in compliance with relevant criteria. For nutrients, it was found that levels of phosphorous were out of compliance with existing site-specific criteria for Clam Bay. Levels of nitrogen were not out of compliance. The results from these past 12 months were then compared against water quality data going back to March 2015. In general. phosphorus concentrations have increased over recent years in a pattern that suggests that the impacts from Hurricane Irma may have had longer--term consequences than was originally anticipated. A timeline of impacts, activities and water quality suggests that the rainy season of 2018 might have brought more phosphorus into the Clam Bay system than even the hurricane- impacted prior year. This may have been associated with activities that were conducted in 2018 to reestablish tidal channels in the mangrove forests adjacent to Clam Bay. These channels were reestablished in large part due to damage to the forests that occurred in response to the passage of Hurricane Irma in September 2017. Based on data from throughout the Clam Bay system, there is a positive correlation between phosphorous concentrations and the amount of algae in the water column, and an inverse correlation between phosphorous and levels of dissolved oxygen (DO). These results suggest that phosphorous concentrations are at potentially problematic levels in Clam Bay, and they should be carefully monitored, to ensure that conditions do not deteriorate, and that the recent impairments do not become a long-term condition. Should phosphorous continue to exceed established criteria; the County might wish to consider developing a site-specific phosphorus loading model, to develop appropriate management responses. Similar trends were found for nitrogen. but phosphorus tended to explain more of the variability in levels of chlorophyll--a and DO than was found for nitrogen. These data suggest that both nitrogen and phosphorus are important for the management of water quality in Clam Bay, but phosphorus might have more of an influence on ecosystem health than nitrogen. Agenda item#6a Page 2 of 5 Unfortunately, the trend over the past five years has been of an increase in both nitrogen and phosphorus, at least in Outer Clam Bay. Upper and Inner Clam Bay do not show the same trend of increased nitrogen and phosphorus that was seen in Outer Clam Bay. However, despite the trends of increased nutrient concentrations, the majority of stations did not exhibit a concurrent increase in the amount of algae in the water column, as quantified by concentrations of chlorophyll-a. The waters of Clam Bay would be considered to be out of compliance with existing DO criteria used by the state of Florida. This conclusion is consistent with the results of the previous annual report which identified sufficient depressed DO concentrations to be considered out of compliance over the 12- month period. However, a formal determination of impairment for DO by FDEP would require the review of data over a /.5-year period, rather than an individual year. Nonetheless, it would be helpful to better characterize the benthic habitats in Upper and Inner Clam Bay, as it is not that unusual for mangrove-lined creeks to have healthy ecology, even if they "fail" state-designated water quality criteria. While the amount of copper in the various treatment ponds sampled along the eastern border of Clam Bay exceeded criteria for freshwater water bodies. the open waters of Clam Bay would not bp considered to be impaired for copper. That finding seems to represent an improvement in water quality in the bay, most likely associated with reductions in the amount of copper-containing herbicides used in the Pelican Bay stormwater treatment system. 2 Agenda item#6a Page 3 of 5 Table 1.Representation of frequency of impairment for TP for different site and date combinations. Green represents samples in compliance with criteria. Red cells indicate exceedance of criteria. Red cells with an "X" represent values that are within 5%of criteria concentrations,suggesting lack of compliance should be interpreted with caution,due to analytical precision. Clear cells represent a lack of data. Sampling Station Event 1 2 3 4 5 6 7 8 9 Mar-15 --- Mar-15 \/5 Apr-15 Ma 15 Jun-15 1 Jul-15 } Aug-15 ----- ----- --- t'A610 Sep-15 t Oct-15 Nov-15 ----F------- . .� � ----------- .-- — - -..._ Dec-15 Jan-16 Feb-16 g Mar-16 1 �_ Apr-16 — —._.. /, May-16 „�,�,....-. \/ ttwk -- -- -".-—- Jun-16 - 1V 1u1-16 Aug-16 _L..� Sep-16 lVlO Oct-16 .;. _,L, _._ .. Nov-16 _ Decc16 Jan-17 ' Feb 17 41. ; _ Mar-17 Apr-17 '.-- -.--' a `/, May-17 G, Jun-17 Jul-17 Aug-17 Oct-17 ��- Nov-17 - Dec-17 Jan-18 Feb-18 Mar-18 Apr-18 1r/t.2 May-18 Jun-18 Jul-18 Aug-18 / Sep-18 V 7 t Oct-18 8 Agenda item#6a Page 4 of 5 Sampling Station _! Event 1 2 3 4 5 6 7 8 9 Nov-18 Dec-18 Jan-19 Feb-19 Mar-19 (6� Apr-19 / - May-19 Jun-19 V6 Jul-19 N Aug-19 Cb�.. l o Sep-19 Oct-19 Nov-19 Dec-19 3 3 H z..� L3 2 y 29 1 --1 2. 2. Table 2. Representation of frequency of impairment for TN or differen site and date combinations. Green represents samples in compliance with criteria. Red cells indicate exceedance of criteria. Red cells with an "X" represent values that are within 5% of criteria concentrations,suggesting lack of compliance should be interpreted with caution, due to analytical precision. Clear cells represent a lack of data. Sampling Station Event 1 2 3 4 5 6 7 8 9 Mar-15 Mar-15 Apr-15 1 May-15 ., _. I- 41Pi.. = Jun-15 Jul-15 Aug 15 — — — .-- Sep-15 Oct15 — .. Nov-15 Dec 15 Alliiii _4 — — Jan 16 Feb-16 i Mar 16 Apr16 i May16 --- Jun-16 Jul-16 Aug 16 — — — Sep-16 Oct-16 1 , Nov-164. Dec-16 Jan-17 Feb-17 _-- _- ..- Mar-17 Apr-17 -- 1 1 Table 6. Copper values at sites Clam Bay 1 to 9, in units of pg/ liter. Values highlighted in yellow exceed copper criteria for Class II waters (3.7 pg Cu/ liter). Station 1 2 3 4 5 6 7 8 9 1/14/2019 3.2 2.7 2.1 1.9 1.6 1.6 1.6 1.6 1.6 2/25/2019 3.4 2.5 2.0 1.9 1.6 1.6 1.6 1.6 1.6 3/25/2019 1.8 3.1 1.6 2.7 1.6 1.6 1.6 1.6 1.6 4/11/2019 2.3 2.5 1.7 1.9 1.6 1.6 1.6 1.6 1.6 5/9/2019 2.3 3.2 2.0 2.7 1.6 1.6 1.6 1.6 1.6 6/25/2019 3.0 2.5 1.7 1.6 1.6 1.6 1.6 1.4 1.5 7/24/2019 2.7 2.0 1.8 1.6 1.4 1.4 1.4 1.4 1.7 8/8/2019 2.8 1.7 2.1 2.1 1.4 1.4 1.4 1.4 1.4 9/5/2019 2.0 1.4 1.4 1.4 1.4 1.4 1.4 1.4 1.4 10/21-22/19 1.9 2.1 2.0 1.5 1.4 1.6 1.6 1.6 1.6 11/19/19 1.4 1.6 1.6 1.6 1.6 1.6 1.6 1.6 1.6 12/16/19 3.0 3.9 2.3 1.8 1.6 1.6 1.6 1.6 1.6 mean 2.5 2.4 1.9 1.9 1.5 1.6 1.6 1.5 1.6 ' median 2.5 2.5 1.9 1.9 1.6 1.6 1.6 1.6 1.6 N 12 12 12 12 12 12 12 12 12 #> 3.7 0 1 0 0 0 0 0 0 0 % > 3.7 0% 8% 0% 0% 0% 0% 0% 0% 0% Of the 108 samples collected for copper, only one of them exceeded the established criteria of 3.7 pg/ liter. Based on guidance in Table 3 of FAC 62-303, Clam Bay is not out of compliance for copper for the sampling period evaluated. The determination of copper exceedances in freshwater sampling sites in the watershed requires the simultaneous collection of data on "hardness". Over this analysis period, all samples from freshwater locations included results on hardness, and those data are analyzed below. The water quality standard for copper differs between predominately marine waters and freshwater. As classified by FDEP, open waters of Clam Bay have a water quality standard for copper of< 3.7 pg/ liter. In contrast, the copper standard for freshwater is more complicated, as it requires the concurrent recording of a value for"hardness" in units of mg CaCO3/liter. The toxicity of copper is mostly restricted to the abundance of the copper ion, and the greater the abundance of other dissolved compounds, the lower the probability that free copper ions will be available to bind with cell membranes, etc. and cause direct and indirect biological impacts. Briefly stated, the higher the hardness level of a water sample, the lower the probability that a given level of copper will be toxic. Once the level of hardness is determined, the copper criterion for a sample collected from freshwater is derived as: 19 Agenda item#6b vL �p� I Page 1 of 1 1. f of !/+ oapL a�� /kVJ -- J tfe ZD , G Table 2. Observed TP Exceedances (marked with an "X") at the ambient Clam Bay surface water sample sites over the period of January 2020 to June 2020. "-" indicates sampling dates without corresponding conductivity data. Boxes with neither an X or a dash are in compliance with existing criteria. *indicates exceedance value was within 5% of criteria. Station Sampling event Jan Feb Mar Apr May Jun 1 X _ X 2 X 3 X X 4 X 5 X 6 X X 7 X X X X 8 X X X* 9 X X* Additionally, water quality data from six of the Clam Bay Outfall monitoring stations were compared to the proposed downstream protective values (DPV) for Clam Bay (PBS&J 2011). Due to concerns related to the Coronavirus pandemic, no samples were collect in April 2020 at the outfall monitoring stations. Outfall TN and TP concentrations were compared to the median and 90th percentile DPV values to determine if elevated concentrations were identified (Appendix B). The median and 90th percentile DPVs for TN are 1.31 and 1.80 mg/L, respectively (PBS&J 2011). The median and 90th percentile DPVs for TP are 0.10 and 0.25 mg/L, respectively. For TN, 36 and 9 percent of the values exceeded the median and 90th percentile DPV criteria, respectively, during the months of May and June 2020 (Table 3). It should be noted that a "median" value represents a value where 50 percent of samples would be expected to be in exceedance. Similarly, it would be expected by chance alone that 10 percent of values would exceed the 90th percentile DPV, vs. the 36 percent of TN values found here. In comparison, 55 percent of TP values exceeded the median DPV criterion and 9 percent of values exceeded the 90th percentile DPV criterion. For nitrogen and phosphorus, the findings reported here are not far out of line for expectations set out in the "hold the line" approach used to develop NNC criteria for Clam Bay. Table 3. Percentage of TN or TP concentrations from outfall stations which exceeded the median or 90th percentile DPV values for stormwater runoff. DPV Total Nitrogen Total Phosphorus Median 90th Percentile Median 90th Percentile Percent of values below 64 91 45 91 Percent of values above 36 9 55 9 6 HUMISTON &MOORE r ENGINEERS I COASTAL 5679 STRAND COURT ENGINEERING DESIGN NAPLES,FLORIDA 34110 AND PERMITTING FAX:23594 25 PHONE::239 594 2021 October 13, 2020 MEMORANDUM To: Neil Dorrill, Director, Pelican Bay Services Division From: Mohamed Dabees, Ph.D. PE. Regarding: Clam Pass condition update. October 2020 We have been monitoring the inlet changes especially over the past few weeks where sand accumulation at the south bank of the inlet persisted and the inlet channel migrated northward. There has been persistent flow of sand from south side of the inlet since the sand placement at the park last winter. Over the summer months wave energy from the south also compound the rate of sand inflow towards the inlet from the south. As a result, the inlet channel is pushing north to flow around the sand build up on the south side of the inlet. The inlet regrade effort in April helped restore tidal flow, but the sand continues to spread toward the channel from the south. The recent erosion of the north inlet bank is a twofold outcome. From one viewpoint, there is enough flow to keep the inlet open and the tidal ratios are still above the critical threshold. On the other hand, the level of erosion of the north bank is concerning due to erosion encroaching on dune vegetation and existing structures. The sand buildup at the inlet mouth is not an elevated dry sand spit, but shoals that get overtopped at highwater allowing gulf water to flow into the pass but then the ebb flow has to find a way around the shoal by scouring the north bank. We will continue to monitor the changes and advise PBSD when conditions become critical and necessitate corrective measures. The inlet regrading and mechanical bypassing operation earlier this year demonstrated a practical way to assist the inlet stability. However, we are still in turtle nesting season until the end of October so available options are limited at this time. The attached exhibit shows a plan view of inlet conditions based on an aerial photo taken on October 8, 2020 with the permitted inlet maintenance template. Our recommendation at this time is to file a request for Notice to Proceed from DEP to regrade the inlet mouth following the turtle nesting season similar to the operational maintenance of April to assist the bypass of some of the sand accumulated on the south side. The project would provide mechanical sand bypassing and regrading the inlet mouth similar to design conditions. Let me know if you have any questions. N �� NO �oN N UYm<E -G 27,2C �mHgn h�N�vL . .111g23 M1.. F- U �N ce A W aQ ta UJ -.r_'^ -..as fir'* z 4414 Zy, ? 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