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many cases, or severely restrict the build-
<br />ing envelope in others. Further, questions
<br />of setback, siting, the location of parking,
<br />ingress and egress, and direct access to the
<br />structure all must be considered if homes are
<br />to be raised or built to their FEMA-required
<br />elevations (or higher). The mitigation of
<br />these changes likewise may mean specific
<br />design interventions to maintain either his-
<br />toric context or neighborhood character.
<br />The Old Mandeville Business District
<br />Area Plan, developed in the wake of Hur-
<br />ricane Katrina, spells out a series of design
<br />regulations and guidelines for homes and
<br />businesses within the district. The goals of
<br />the plan are straightforward: Enable historic
<br />Mandeville to retain its historic context while
<br />allowing for structural elevation that will
<br />mitigate flood impacts and ensure compli-
<br />ance with FEMA regulations.
<br />Following adoption, the city incorpo-
<br />rated the plan's design regulations and
<br />guidelines into its zoning code by reference
<br />(§7.5.1o.5.1). Design regulations in the plan
<br />are heavily focused on screening, regulating
<br />the use of space below elevated buildings,
<br />and mitigating perceptions of height. They
<br />also tend to be sensitive to the particulars
<br />of individual sites. The following constitutes
<br />a brief summary of both site and building
<br />design regulations:
<br />• Site design requirements: Ensuring proper
<br />use of the public frontage including the
<br />provision of pedestrian and on -street
<br />parking space where rights of way exist;
<br />landscaping with shrubs, trees, and
<br />greenery; the use of hedges and fencing
<br />to separate private and public realms; and
<br />screening on -site parking located beneath
<br />the structure with foundation plantings
<br />and vegetative screens. Requirements also
<br />include the screening of piers and columns
<br />that have been used to raise structures with
<br />paneling and plantings of at least half the
<br />height of the piers. Finally, building entries
<br />must face the street on which the building
<br />fronts, and walkways should provide direct
<br />access from the sidewalk to the front door.
<br />• Building design requirements: Uses
<br />below the building Base Flood Elevation
<br />are restricted to access, parking, and
<br />storage. Given the increased height of
<br />buildings due to elevation, specific ele-
<br />ments such turrets, towers, and cupolas
<br />cannot exceed 5o feet in height. Front
<br />entry porches must use materials, colors,
<br />and proportions appropriate for the local
<br />architectural context. Large and multi-
<br />family buildings must use treatments
<br />similar to single-family housing to ensure
<br />local architectural consistency.
<br />Design guidelines included in the plan
<br />function as recommended practices that go
<br />beyond code requirements. These include
<br />guidelines for specific design elements such
<br />as canopies, galleries, and locally significant
<br />materials and colors, and design strategies
<br />for mitigating height and size perception.
<br />The impacts of Hurricane Isaac on Man-
<br />deville in 2012 are notable for entirely different
<br />reasons than Katrina in 2005. While Mandev-
<br />ille experienced a similar storm -surge event
<br />during Isaac, NFIP claims were reduced by half
<br />and financial losses bY71 percent. While much
<br />of this is likely attributable to post -Katrina
<br />flood mitigations (home elevation, community
<br />preparedness, etc.), having a zoning code and
<br />design guidelines that consider NFIP elevation
<br />requirements in addition to neighborhood
<br />context no doubt played a role.
<br />NORFOLK, VIRGINIA
<br />Norfolk, Virginia, is at the leading edge of
<br />incorporating sea -level rise information into
<br />its local planning processes. Notably, the
<br />integration of coastal flood resilience has gone
<br />beyond the inclusion of flood -hazard and sea -
<br />level rise data in various plans and documents,
<br />but has also focused on how flood -hazard
<br />and sea -level rise information can inform
<br />implementation processes such as the capital
<br />improvements program or the zoning code.
<br />Located in the
<br />Chesapeake Bay,
<br />and home to both the
<br />world's largest naval
<br />base and the second
<br />largest port network
<br />on the East Coast,
<br />Norfolk has a long and
<br />enduring relationship
<br />with water. Yet this reli-
<br />ance on the water has
<br />obvious drawbacks,
<br />particularly in an age of
<br />sea -level rise. Norfolk's
<br />awareness of its own expo-
<br />sure and vulnerability is
<br />the driving force behind its
<br />considerable adaptation
<br />efforts, which have recently included a 2013
<br />comprehensive plan update, investment in
<br />local flood -resilient infrastructure, and par-
<br />ticipation in both the Dutch Dialogues and
<br />Rockefeller's 10o Resilient Cities initiative. An
<br />enduring theme of the 2013 comprehensive
<br />plan update revolved around ensuringthat
<br />flood resilience can be operationalized within
<br />the city's array of implementation processes.
<br />To that end, the plan update called for a
<br />revised zoning ordinance that considered the
<br />risks of sea -level rise on the built environment.
<br />The code revision, titled ZoneNorfolk and
<br />adopted unanimously by Norfolk's city council
<br />in January 2018, seeks to tackle the problem
<br />with a strategy that fuses site -specific require-
<br />ments with a districtwide overlay approach.
<br />At the site scale, Norfolk built its most
<br />recent revisions atop earlier elevation require-
<br />ments adopted in 2013. These rules require
<br />an additional three feet of freeboard above
<br />the base flood elevation for buildings within
<br />the Special Flood Hazard Area, and 18 inches
<br />of freeboard in the "shaded X" area, which
<br />includes buildings between the soo-year (or
<br />one percent annual chance) floodplain and
<br />the Soo -year (or point -two percent annual
<br />chance) floodplain (§3.9.7). As a part of
<br />the most recent code revision, the city now
<br />requires builders to elevate all new single-
<br />family detached dwellings outside of defined
<br />flood hazard areas between 16 and 24 inches
<br />(§5.9.3.D). This approach is notable as it con-
<br />siders the likelihood of more extreme flooding
<br />inside of and more extensive flooding outside
<br />of the FEMA-defined flood hazard area, which
<br />is generally based on historic flooding and
<br />doesn't consider sea -level rise.
<br />As a: coastal city, Norfolk has long relied on water as
<br />thelifebloodof its economy.The—prospect of sea —
<br />level rise complicates that relationship
<br />ZONINGPRACTICE 6.i8
<br />AMERICAN PLANNING ASSOCIATION I page 4
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