HomeMy Public PortalAboutCC Workshop 072816.pptxCarrying Capacity Study
Update To City Council
July 28, 2015
City of Tybee Island
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Scope of Work
Technical Advisory Group
Community Resources Inventory & Assessment
Analysis of Community Resources Limitations
Recommendations & Implementation Plan
Coordination with Comprehensive Plan Process
Scheduled to be completed in October 2016
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Public Involvement
Technical Advisory Group – 3 Meetings
Comprehensive Plan Joint Meetings – 4 Meetings
Infrastructure/Staff Meeting – 1 Meeting
Future Meetings:
Technical Advisory Group
Planning & Zoning Commission
City Council
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Human Application of Carrying Capacity
I = P x A x T
I = Environmental Impact
P = Population
A = Affluence
T = Technology
Human carrying capacity is not strictly related to population size, but to many levels of consumption, which are in turn impacted by technology and the economy.
Local governments have the opportunity to opportunity to impact these variables through regulatory and policy choices related to land use, infrastructure improvements, growth management,
and the local economy.
Wave Ecology and Highway 80 Challenge Study 2011
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Carrying Capacity Community Resources Inventory and Data Assessment
Population
Water Withdrawal
Wastewater Discharge
Traffic Counts & Parking
Short Term Rental Units
Zoning
Solid Waste
Flooding/Sea Level Rise
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Population
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Tybee Population - Resident
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Historical Population
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Housing Units – Census
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Short Term Rental units
* Tybee Tourism Study estimates 4.3 people per unit, which equals a maximum short term rental population of 7,473
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Short Term Rental Population
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Second Home Population
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Traffic Counts
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Traffic Counts & Daytime Population
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Population
1Does not account for Second Home Population
2Short Term Rental + Second Home Population
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Water Withdrawal
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Water Withdrawal
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Water Withdrawal – Future Permit Limits
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Per Capita Water Usage
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Future Water Withdrawal Demand
*Per Capita Water Demand 115 GPD
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Wastewater Discharge
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Wastewater discharge
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Wastewater Discharge
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Parking Statistics
Public Parking Spaces (Delineated) = 2,091
Private Parking Spaces (Permitted) = 234
Additional non-delineated ROW & parking at private homes provides additional spaces
Parking Areas & Capacity on Summer Weekends
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Solid Waste – Residential Trends
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Solid Waste – non-Residential Trends
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Nuisance flooding
2016, January. Evans, Jason et all. Tybee Island Sea-Level Rise Adaptation Plan
Draft for Official Review and Comment, National Sea Grant College Program
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Sea Level Rise/Flooding
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Flooding of Highway 80
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Vulnerabilities Identified in the Sea Level Rise Study
• Failures of the local stormwater management system
• Flooding of roads, particularly US Highway 80
• Increased beach erosion
• Saltwater intrusion
• Higher and stronger storm surges
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Zoning Analysis Preliminary Results
Current conditions
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Zoning Analysis Preliminary Results
Future Build Out
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R2 Zoning - Population Growth implications
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Future Water Withdrawal Demand
*Per Capita Water Demand 115 GPD
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Understanding of Carrying Capacity goals
Diverse and stable year-round population with a high quality of life
Sustainable tourism-based economy that also serves year-round population and business owners in the off-season
Balance between the needs of the tourism industry and year round residents
Protection of Tybee Island’s environmental, historic and cultural resources
Safe multi-modal access to, from and within Tybee Island for residents and visitors
Adapting to a changing climate
Political and public support for implementation of the plan recommendations
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Identification Of Issues/impacts - Water
Issues
Permit limitation
Peak usage associated with tourist population
Cost of needed capital improvements
Potential Strategies
Cretaceous Well & Treatment Plant
Education for tourist, kids, development community
Gray water usage
Rate study
Incentives for conservation
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Identification Of Issues/impacts - Wastewater
Issues
Peak wastewater discharge issues associated with tourists
Compounding effects of I&I.
Capacity of WWTP infrastructure
Potential Strategies
Upgrade WWTP
Potential water quality issues from discharge
Lack of space for WWTP expansion
Permitting and environmental impacts of upgrading discharge pipe
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Identification Of Issues/impacts - Stormwater
Issues
Nuisance flooding associated with king high tide and rain events.
Sea level rise is exacerbating flooding
Additional development may also exacerbate flooding
Cost of infrastructure upgrades
Water quality issues that result from flooding
Potential Strategies
Sea Level Rise Study recommended improvements
Limiting impervious surfaces
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Identification Of Issues/impacts – Traffic/Parking
Issues
Peak traffic flow issues related to day-trippers and events
Flooding of Hwy 80 and other roads on-island
Traffic related to accidents on Hwy 80
Parking availability and available land to accommodate it
Illegal parking and congestion in residential areas
Lack of alternative modes of transportation
No public harbor to allow for ferry service to Savannah
Potential Strategies
Cost/benefit analysis of parking lot in C1
Remote parking with transportation
Multi-modal opportunities for transportation to and within Tybee Island
Notifying people about traffic congestion and parking issues
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Identification Of Issues/impacts – Short Term Rentals
Issues
Peak water & wastewater usage on the island is driven by short term rentals
Short-term rentals are a component of all above elements, but are also important to the economy of the island
Conversion from short-term rental to year round also has impacts that need to be considered
Strategies
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Identification Of Issues/impacts – City Funding
Issues
Need for reserves in the general fund for disaster preparedness and infrastructure improvements
Capital costs for known projects
Strategies
Rate study for water & wastewater infrastructure improvements
City position for coordination with tourism industry
Stormwater utility feasibility study
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Identification Of Issues/impacts - Zoning
Issues
R-2 Zoning build out
R-2 zoning area of Tybee is already flooding at King tides.
Strategies
Revise R2 cost to decrease subdivision
Limit areas zoned R2
Identify areas appropriate for growth (Commercial districts) and steer growth there, i.e. TDR.
Spread development out over a long period of time through permitting limitations.
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Identification Of Issues/impacts - Litter
Issues
Litter on beach
Solid waste disposal trends are still increasing not decreasing as was expected with the advent of recycling
Strategies
Reduction of waste generation on island
Alternatives for solid waste disposal in landfills off island
Waste reduction education & litter education
Enforcement of Litter ordinance
Incentives/programs to encourage better compliance on the beach
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Next Steps
Finalize & Prioritize Strategies to Address Issues
Complete Carrying Capacity Report
Final Presentation to Council in September
Presentation to CRD at Brown Bag luncheon
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