Architecture and Building: The importance of feasibility studies – Building in flood zones

Filed Under: July 2017 Issue, Toolbox Articles

By Tim Sawyer
Building a new beach facility with public restrooms and amenities at a frequented beach on Cape Cod might seem like a no-brainer! It could strengthen the area as a destination for residents and tourists and potentially brings in additional revenue for the town.
But before the design process starts in earnest, there is a very important step that could save a lot of headache and money: the feasibility study. Even if there was an existing structure, new code requirements may force a very different design solution from what may be anticipated.
FEMA flood maps have changed, as have many of the code regulations with regard to building in these areas. A feasibility study is an early and necessary step in the design process where many of the unknowns are uncovered, quantified and estimated through a preliminary design and budget. This early and relatively low-cost project due diligence can provide valuable information to decision makers who are tasked with choosing what projects should move forward and which ones are not feasible, either from a construction or cost (or both) perspective.
Case Study: Municipal Beach Facility on Cape Cod
A Cape Cod allocated fund to complete a feasibility study at a local town beach to determine how public restrooms and other public amenities might be accommodated. They reasonably imagined a modest, classic Cape Cod structure nestled in the dunes at grade. What resulted from the feasibility study was eye-opening and far from what was anticipated by the town officials or the general public.
Through site analysis and review of various federal, state, and local codes and regulations, the architect started to paint the picture of how the design of any structure at this site would be impacted. The site contained many of the most restrictive constraints such as FEMA Velocity flood zone, Coastal Dune Resource Areas, rare species habitat as well as a designated high wind area. All these factors contributed in varying degrees to the building design approach.
The most striking constraint was the FEMA Velocity flood zone which for this site, was atelevation 16 feet (above sea level). The velocity aspect imposes an additional requirement of 2 feet of free board (additional vertical distance to the bottom of lowest structural member) as well as an open foundation (no solid walls). By taking 16 feet for base flood elevation + 2 feet of free board + estimated 2 feet structural floor depth, the finished floor elevation was at approximately 20 foot elevation. The surrounding parking lot grade is 10 foot elevation resulting in a first floor elevated 10 feet above adjacent grade on an open pile type foundation. Federal and state (ADA and MAAB) accessibility requirements would be accomplished via a series of ramps and landings totaling ±150 linear feet and nearly 1,000 square feet as well as an elevated deck area of ±1,600 for circulation into and around the elevated first floor.
The building’s location was restricted to over existing parking lot footprint only, further resulting in the loss of existing parking spaces. Coastal dunes are a prohibited area for construction and are protected habitat for various rare bird species.
The site constraints discussed above are only a few of the many factors influencing the building’s preliminary siting and design, but they represent some of the most striking and far reaching design requirements. The extraordinary design solutions resulting from the constraints of this particular site also come at significant added expense over more conventional ground level and non-flood zone construction.
The completed feasibility study provided the town with multiple options and preliminary budgets for how restrooms and other public amenities might be provided at this specific Town Beach. This relatively low cost study brought to light significant factors which would impact any design and associated budget prior to investing significant capital to the project.
Flood zones, exorbitant insurance claims from numerous recent coastal storm events, as well as ever-tightening construction code regulations have changed significantly over recent years and the need for construction of resilient buildings in high-risk areas will continue to have significant impact on the design approach and cost of construction. The public generally doesn’t understand the impacts these regulations have on design and construction costs. It cannot be assumed that what was designed and built on one site would meet the current requirements on another because every site has its own unique constraints and opportunities.
Timothy R. Sawyer is an Associate Architect and Project Manager at Brown Lindquist Fenuccio & Raber Architects Inc. He can be reached at or (508) 362-8382.

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