COASTAL FLOODING - THE FORT LAUDERDALE TIDAL VALVE PROGRAM

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1 COASTAL FLOODING - THE FORT LAUDERDALE TIDAL VALVE PROGRAM Elkin Diaz, MBA, PE, PMP LEED Green Associate Senior Project Manager Public Works Department ediaz@fortlauderdale.gov

2 Community Priorities: Vision & Survey Current Challenges and Limitations Stormwater Approach + Adaptation Action Areas Storm Flooding - Tidal Flooding Project Case Fort Lauderdale Tidal Valves

3 NEIGHBOR SURVEY RESULTS 1. Level of satisfaction with flooding prevention : 34% 2. Neighbors that have observed increased flooding: 68% 3. Neighbors that have observed increased coastal water levels: 70% 92 total Infrastructure ideas & 22 ideas to improve drainage STRATEGIC PLAN - PRESS PLAY FORT LAUDERDALE 2018 Infrastructure Cylinder Goal 2: Be a sustainable and resilient community. Objective 1: Proactively maintain our water, wastewater, road and bridge infrastructure Objective 2: Reduce flooding and adapt to sea level rise COMMISSION ACTION PLAN ITEM

4 High groundwater table Low-lying residential streets Sea level rise Low and deteriorating seawalls Aging infrastructure Absence of stormwater infrastructure Lack of green space

5 Estimated threshold for flooding in low lying areas in Fort Lauderdale 1.3 feet NAVD (2.88 NGVD)

6 Observed (2.6 ft) Predicted (1.59 ft) Average (0.45 ft)

7 Community Priorities: Vision & Survey Current Challenges and Limitations Stormwater Approach + Adaptation Action Areas Storm Flooding - Tidal Flooding Project Case Fort Lauderdale Tidal Valves

8 Phase I (1-5 year Plan): (estimated cost $12 million) Design & Construction of 37 localized flooding projects Stormwater rate and funding Phase II (3-5 year Plan): (estimated cost $190 million) Survey & data collection; New LIDAR Hydraulic Modeling ICPR4 (Groundwater Modeling) Complete Final Engineering Plans for neighborhoods Develop Cost Estimates and LOS recommendations Phase III (10 year Plan): (estimated cost $900 million ) Construction of neighborhood projects Long-term solutions for our changing conditions Requires additional funding and procurement process (CCNA)

9 Optional designation in local government s comprehensive plan for Areas At risk of flood damage and erosion due to high tides, storm surge, and climate change. Purpose: Prioritizing funding for infrastructure needs, Increase City s resiliency to SLR & Climate Change, and Adaptation Planning. Jan AAA Program incorporated into the City Comprehensive Plan as allowed by Florida Statutes ( (1) & (6) In partnership with S.F. Regional Planning Council & Broward County AAA Identification Process: Areas below tidal water elevation Areas with hydrological connections to coastal waters Areas that serve as storm surge evacuation zones Program uses a 5-Year strategic Plan Made possible through partnership with NOAA, Florida Dept. of Economic Opportunity, BC, and SFRP Council.

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11 Community Priorities: Vision & Survey Current Challenges and Limitations Stormwater Approach + Adaptation Action Areas Storm Flooding - Tidal Flooding Project Case Fort Lauderdale Tidal Valves

12 2016 LIDAR

13 Storm Flooding (Mostly West of US-1) Tidal Flooding (Mostly East of US-1)

14 Las Olas Boulevard

15 NE 20 th Ave (From Sunrise Blvd to NE 7 Street)

16 Henricks Isle Drive

17 Riviera Isles (Flamingo Drive, Solar Isle Drive, & Riviera Drive) - Videos

18 NE 15 Street West of Intracoastal Waterway

19 1610 SE 10 Street (Before)

20 1610 SE 10 Street (After)

21 BUILDING CANAL SEA WALL roadway INFILTRATION TIDES BACKFLOW GROUNDWATER FLOW ISSUE 1 TIDAL BACKFLOW ISSUE 2 INFILTRATION ISSUE 3 GROUNDWATER FLOW

22 Traditional Tidal Control Valves Flap Gate Valves

23 Traditional Tidal Control Valves Duckbill Check Valves

24 Traditional Tidal Control Valves Duckbill Check Valves

25 BUILDING CANAL SEA WALL PRB roadway TIDES BACKFLOW GROUNDWATER FLOW ALUMINUM GRATE INLINE CHECKMATE TIDE BACKFLOW PREVENTOR VALVE

26 Tidal Valves - Inline Checkmate valves

27 Tidal Control Valves- Wastop Valves

28 Retrofitting to Reduce Tidal Flooding 133 Tidal Valves Installed ~13 for FY2017 Avg. Cost 12 Valve - $4,250 Basin Retrofit - $20,000 Aprox. Annual Maint. - $4,000

29 Tidal Valves Las Olas Isles

30 Tidal Valves Riviera Isles

31 Community Priorities: Vision & Survey Current Challenges and Limitations Stormwater Approach + Adaptation Action Areas Storm Flooding - Tidal Flooding Project Case Fort Lauderdale Tidal Valves

32 17 Inline tidal valves were installed for Riviera Isles during FY 2011

33 Solar Isle Drive (Before)

34 Solar Isle Drive (After)

35 17 Inline tidal valves were installed for Riviera Isles during FY 2011

36 o Portable o Adjustable to fit pipe o Non-corrosive o Flexible Neoprene Elastomer o Opens with minor flow pressure o Placed inside pipe to prevent sun damage o No barnacles growth o Easy storage o Requires annual maintenance Program o Maintenance includes keeping street debris from reaching the valve o Manufacturer recommends quarterly maintenance cycle o Available through two manufacturers (Tide Flex, WaStop.)

37 Based on the Riviera Isle Pilot Project, the following is an estimated COST BREAKDOWN for using the valves: o Material Cost o Installation Cost o Projected Annual Maintenance Cost o Projected Replacement Cost (after valve s life expectancy) o Incidental Costs (Work on private property)

38 Inline CheckMate Valves (Tidal Control) Cost Variables: Sizes: 4 inch - 72 inch Materials: Neoprene, Nylon, Polyester, Others Clamping Mechanisms: Bands, Flanges Shapes: Circular, Elliptical, Rectangular, Arched For circular, neoprene, w/ Bands Price Range: $600 - $65,000

39 WaStop Valves (Tidal Control) Cost Variables: Sizes: 3 inch - 72 inch Materials: Steel Insert, Neoprene Elastomer Clamping Mechanisms: Bands, Flanges Shapes: Circular For circular, neoprene, w/ Bands Price Range: $1,000 - $112,000

40 Valve Installation + Stormwater Outfall Improvements: 1. Replace old street catch basin with a new one 2. Tie existing drainage pipe to new basin 3. Install the inline checkmate Tide flex valve 4. Install a new pollution control baffle at new catch basin (reduces debris getting into valve) 5. Install an aluminum screen at the seawall / canal side (prevents large debris from going inside pipe) 6. Restore asphalt roadway and concrete sidewalk or curbing affected by trenching Approx. Cost: $20K-$25K / EA

41 Approx. Cost: $20K-$25K / EA

42 The ANNUAL maintenance cost per outfall valve includes the following tasks (quarterly cycle): 1. Remove debris & standing water from basin via pump and sediment tank(s) 2. Remove pollution control baffle from basin 3. Clean debris from basin and valve by pressure clean and vacuum 4. Inspect the valve is tight and adjust clamps as needed 5. Re-install pollution control baffle in basin Approx. Cost: $ 4,000 / YR 6. Close basin with grate or cover 7. Write Inspection report

43 o o o Tideflex Inc, manufacturer of the valve states that the inline checkmate valve has a life expectancy of 25 years (life cycle). Factors that contribute to the decline of the service life cycle of the valve may include damage by improper installation or during mounting/demounting of a maintenance event. A replacement cost includes the tasks involved during a maintenance plus replacing the old with the new valve at end of life cycle. Approx. Cost: ($ 3,000 + valve cost) / EA

44 During the Pilot project at Riviera Isles, incidental costs were encountered from retrofitting the outfall pipes & installing the new tide flex valves, including: o o o o Existing drainage piping was found broken and had to be replaced and/or lined, so the valves could work as intended. Additional outfalls were found during construction (and retrofitted), which were not shown on City records. Outfall surface features (such as landscaping hedges, palms, fences) needed to be removed and re-placed when pipe was trenched/installed. City staff hours (by legal, survey, and engineering departments) were spent searching for drainage easements or recording new drainage easements for outfall pipes.

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47 o o o o o o Mitigation / Prevention of road flooding during high tides Prevent damage to landscaping caused by sea water Prevention of stinky marine sea smell pushed inland Minimization of traffic jams Minimization of Pedestrian traffic hazards due to flooded roads Improvement of water quality from installation of PRBs

48 o o o o o o Successful results Feasible Alternative vs. other solutions Cost effective Requires investment in maintenance program Requires investment in Public education Improvement of water quality & pollution Control NE 11th Court NE 11th Court 10/2016