Prepared By: Cutcher & Associates, Inc. Coastal Engineers Jupiter Reef Club Replacement Seawall Conceptual Design Overview August 25, 2016 Prepared By: Cutcher & Associates, Inc. Coastal Engineers

Seawall Replacement Design Criteria Structural Stability & Longevity Permitability Construction methodology relative to site limitations Cost Construction Schedule Vibration impact to existing structures Impact to tenants & guests Funding cycle

Existing Seawall: - Does not provide the structural stability to meet the environmental loads resulting from a significant storm event (1). - Existing geometry and age prevents cost effective further restoration efforts Partial failure would be catastrophic Loss of upland infrastructure likely, inability to permit future structure (1) JUPITER REEF CLUB STRUCTURAL ANALYSIS OF EXISTING SEAWALL, JULY, 2016

Replacement Seawall Conceptual Design Two Basic Approaches Steel Sheet Pile & Concrete Cap Cantilever & Restrained East of existing seawall – Difficult to permit, most expensive, construction challenges West of existing seawall – Easier to permit, not feasible Reinforced Concrete Counterfort geometry – Easier to permit, difficult to construct, prohibits use of deck area Duplicate existing geometry – Permitable, most cost effective

Two Basic Approaches Six Conceptual Designs Option 1A - Offset Balanced Cantilever w/ steel sheet pile stem east of existing seawall Option 1B - Same as 1A but with increased concrete thickness Option 1C - Same as 1A but substitute FRP sheet, add micro piles Option 2 - Cantilever Steel Sheet Pile, east of existing seawall Option 3 - Concrete Counterfort w/ sheet pile stem wall west of existing seawall Option 4 - Cantilever Steel Sheet Pile, west of existing seawall

Option 1A - Offset Balanced Cantilever w/ steel sheet pile stem, east of existing seawall

Option 1B - Same as Option 1A but with thickened concrete section

Option 1C - Same as Option 1A but substitute FRP sheet pile, add micro piles

Option 2 – Cantilever steel sheet pile w/ concrete cap, east of existing seawall

Option 3 - Concrete counterfort w/ steel sheet pile stem, west of existing seawall

Option 4 - Cantilever steel sheet pile w/ concrete cap, west of existing seawall

Ease of Permitting Least Difficult – Options 3 and 4 Moderate Difficulty w/ Justified Rationale – Option 1C Moderate Difficulty – Option 1A, 1B Most Difficult – Option 2 Anticipated permitting timeline: 120 – 180 days

Constructability Least Difficult – Options 1C Option 1A Option 1B Moderate Difficulty – Option 3 Most Difficult – Option 2 Option 4 is not included since it would not be feasible

Construction Cost – Initial Estimate Least Expensive – Options 1C: $1.6 Million Option 1A: $1.75 Million More Expensive – Option 3: $1.84 Million (does not include removal of existing structure) Option 1B: $1.92 Million Most Expensive – Option 2: $2.2 Million (does not include Giken machine) Option 4 is not included since it would not be feasible

Anticipated Construction Schedule Ordering & delivery of materials – 30 days Mobilization of equipment – 14 days Site preparation & create beach access – 14 days Sheet pile installation & concrete forming – 60 days (assumes suitable weather and continued beach access) Site clean up & demobilization – 7 days

Considerations The existing seawall is vulnerable to a significant storm event (erosion in front of wall + saturated soil behind wall) The existing toe wall sheet pile will continue to degrade – The rehabilitation did not address this (if the toe wall sheets fail, so does the seawall) Statistical likelihood of such a storm increases with time (50 yr return interval storm has a 2% likelihood per year, over five yrs. there is 10% chance of occurrence) Wall failure would likely be catastrophic (considerable loss of upland fill, damage or loss of pool, possible damage to residences) Frequency of Occurrence and Intensity is forecasted to increase (current return interval storm models do NOT consider global climate change predictions)