Climate Change and Coastal Hazards: Assessment for Long-Term Master - PowerPoint PPT Presentation

Climate Change and Coastal Hazards: Assessment for Long-Term Master Water Plan Tampa Bay Water UF Water Institute Symposium February, 2020

Who Is Tampa Bay Water? New Port Richey Tampa St. Petersburg 2

Tampa Bay Water’s System • Integrated supply system • 13 wellfields • 8 groundwater treatment facilities • Surface Water Treatment Plant • Desalination Treatment Plant • 9 pump stations • 270 miles of transmission mains 3

Regional Supply Sources • Population served: 2.5 million Population served: 2.5 million – Regional average annual demand 220 mgd to 259 mgd Regional average annual demand 220 mgd to 259 mgd • Supply sources Supply sources – Groundwater Groundwater - permitted capacity 90 mgd ( permitted capacity 90 mgd ( capacity 120 mgd capacity 120 mgd ) – Surface Water Treatment Plant Surface Water Treatment Plant – permitted capacity 120 mgd permitted capacity 120 mgd • Sustainable capacity 99 mgd; hydrology Sustainable capacity 99 mgd; hydrology -dependent dependent – Seawater Desalination Treatment Plant Seawater Desalination Treatment Plant – permitted capacity 25mgd permitted capacity 25mgd • Sustainable capacity 16 mgd; drought resistant Sustainable capacity 16 mgd; drought resistant • Off Off-stream regional reservoir stream regional reservoir – 15.5 billion gallons capacity 15.5 billion gallons capacity 4

Regional Demand Projections Phase 2 - 10 MGD Phase 1 – 10 MGD 5

2018 Long-term Master Water Plan Projects Approved for Further Studies Three Water Supply Projects New Groundwater Water Treatment Plant with Desalination Facility Surface Water Treatment South-Hillsborough Expansion with existing Plant Expansion with Aquifer Recharge Project source water existing source water credits South County Projects New Groundwater Treatment via Aquifer Recharge Credits via SHARP Pipeline from Regional SWTP to South Hillsborough County 6

Addressing Climate Change and Coastal Hazards 7

Water Utility Climate Alliance Vision: Climate Vision: Climate -resilient water utilities, thriving communities resilient water utilities, thriving communities Mission: Collaboratively advance water utility climate change Mission: Collaboratively advance water utility climate change adaptation adaptation 8 http://www.wucaonline.org http://www.wucaonline.org

Florida Water & Climate Alliance (Florida WCA) Collaborative Actionable Locally Relevant A stakeholder/scientist network advancing the relevance and usability of climate information, data and tools at local scales to help improve decision-making at an operational level. http://www.floridawca.org 9

Climate Change Effects on Florida • Surface temperatures projected to increase 4-8 ° F by 2100 – Tampa Bay expected to see 2’-8.5’ sea level rise by 2100 • Vulnerability to heat waves and days with max temp exceeding 95 ° projected to increase • Health effects on vulnerable population projected to worsen • Disruption in essential services projected to increase • Urban areas experiencing shorter, intense wet seasons relative to rural areas – Wet season length decreased by ~3.5 hours in the last 40-60 years 10

Long-term Master Water Plan – Vulnerability Assessment • Vulnerability Assessment: – Flooding and storm surge from hurricanes – Sea level rise – Short and long- term water quality impacts • Assessment performed on potential future projects – Some project concepts evaluated have not moved forward 11

Storm Surge Analysis • SLOSH (Sea, Lake, and Overland Surge from Hurricanes) NOAA model used • Model results indicate: – Surge increased as the speed of advance increased for storms moving E and NE – Surge levels related to tide stage – Surge increased as the hurricane category increased – Worst-case hurricane approach moving ENE 12

Storm Surge Analysis 13 Category 5 Category 4

Facilities Affected by Storm Surge Surge Elevation Surge Elevation Surge Elevation Surge Elevation Approximate Low Approximate Low Category 4 Category 4 Category 5 Category 5 FACILITY FACILITY Ground Elevation Ground Elevation Hurricane Hurricane Hurricane Hurricane (NAVD88) (NAVD88) (Feet, NAVD88) (Feet, NAVD88) (Feet, NAVD88) (Feet, NAVD88) Regional Surface Water Treatment Plant Regional Surface Water Treatment Plant 34 Adjacent to 25.2 Adjacent to 29.6 Seawater Desalination Plant Seawater Desalination Plant 9.5 22.7 27.1 New Gulf Coast Desalination Facility New Gulf Coast Desalination Facility 1 9 21.6 25.6 1 New South Hillsborough Wellfield and Groundwater WTP New South Hillsborough Wellfield and Groundwater WTP 100 NA NA New Tampa Augmentation Project Wellfield New Tampa Augmentation Project Wellfield 1 43 NA NA 1 New Advanced WTP (at Regional Facilities Site) New Advanced WTP (at Regional Facilities Site) 34 Adjacent to 25.2 Adjacent to 29.6 New Treated Reclaimed Water Recharge & Recovery Wellfield and WTP New Treated Reclaimed Water Recharge & Recovery Wellfield and WTP 1 100 NA NA Hillsborough Co. SHARP Recharge Wellfield Hillsborough Co. SHARP Recharge Wellfield 2 6 22.8 to 23.5 27.2 to 28.4 Hillsborough County South County AWTP Hillsborough County South County AWTP 2 38 NA NA City of Tampa H. F. City of Tampa H. F. Curren Curren AWTP AWTP 2 9 23.5 27.8 14

Sea Level Rise in Tampa Bay • 2ft – 8.5ft of SLR by 2100 • High uncertainty in future projections 15

Facilities Affected by Sea Level Rise Surge Elevation Surge Elevation Surge Elevation Surge Elevation Approximate Low Ground Approximate Low Ground FACILITY FACILITY Plus Intermediate Low SLR Plus Intermediate Low SLR Plus Intermediate High SLR Plus Intermediate High SLR Elevation Elevation Projection Projection Projection Projection (NAVD88) (NAVD88) (Feet, NAVD88) (Feet, NAVD88) (Feet, NAVD88) (Feet, NAVD88) Seawater Desalination Plant Seawater Desalination Plant 9.5 23.8 24.8 New Gulf Coast Desalination Facility New Gulf Coast Desalination Facility 1 9 22.7 23.8 New Tampa Augmentation Project Wellfield New Tampa Augmentation Project Wellfield 1 22 25.2 26.2 Hillsborough Co. SHARP Recharge WF Hillsborough Co. SHARP Recharge WF 1 6 23.9 to 24.6 25.0 to 26.8 Hillsborough County South County AWTP Hillsborough County South County AWTP 2 38 23.1 24.1 City of Tampa H. F. Curren AWTP City of Tampa H. F. Curren AWTP 2 9 24.6 25.6 16

Overall Vulnerability Assessment • Hazards considered for overall analysis: – Flooding 25% • 5=within inundation area; 3=marginal/adjacent; 1= outside of flood area – Storm Surge 35% • 5=within surge area; 3=marginal/adjacent; 1= outside surge area – Sea Level Rise 15% • 5=within surge area Cat 4+1.7ft; 3=marginal/adjacent +1.7ft; 1=outside flood area – Changes in Water Quality and Availability 25% • 5=significant changes in quality/availability; 3=minor changes in quality/availability; 1=impact unlikely 17

Results of Vulnerability Assessment 18

Climate Change Plan • All plans must consider multiple futures • Robust plans for multi -scenario A Near-term strategy future better than an optimal plan D B for a single -scenario future. Present • Plans must be flexible and C Decision Points adaptive Future • Each scenario offers options for adaptation Credit: DMDU Society; deepuncertainty.org 19

Communication and Public Engagement • Engaging the public is crucial and challenging – Human lifespans vs. climate timescale – Psychological barriers (i.e. “the ostrich effect”) – Uncertainty often equated to complete lack of knowledge (i.e. “throwing the baby with the bathwater effect”) Credit: Water Utility Climate Alliance – How are we going to pay for it? 20

Authors’ Credit Ivana Kajtezovic, Planning Program Manager, Tampa Bay Water Tirusew Asefa, Ph.D., P.E., Planning & Decision Support Manager, Tampa Bay Water Ken Herd, Chief Technical Officer, Tampa Bay Water Andre Dieffenthaller, Vice President, Hazen & Sawyer Stephanie Ishii, Principal Scientist, Hazen & Sawyer 21

Questions