Cost-Effective Hazard Mitigation Measures

• Anchor small support buildings at risk of uplift or rollover.
• Elevate, wet floodproof or dry floodproof buildings, including flood barriers and nature-based measures such as rain gardens, bioswales and wetlands.
• Underpin footings undercut by scour; use stronger siding with stronger attachments; replace vents with water-resistant vents.
• Brace non-structural components (interior walls, partitions, parapets, veneer, light fixtures, drop ceilings, soffits) and secure replaced furnishings.
• Outside the wildland-urban interface (where building code policy already requires them), create defensible space and use non-combustible materials for facilities with wildfire risk.
• Roofs: compatible, corrosion-resistant clips and connectors; strengthen corners, soffits, overhangs and openings; fully adhered low-slope coverings (no loose-laid membranes or ballast); hip framing in place of gable ends; upgraded gutters and downspouts.
• Doors and windows: better weather stripping; wind-resistant doors, frames and hardware; stronger windows; impact-resistant glass; shutters for critical facilities, debris-exposed lower floors, high-value-content buildings, or buildings near likely debris sources.
• Replace impervious paving with permeable pavement, including aggregate and geotextile layers.
• Safe rooms must be within the footprint of the facility being repaired and meet FEMA P-361.

Designs and specifications for the building measures; for safe rooms, designs meeting FEMA P-361 criteria within the footprint of the damaged facility.

• Mechanical, electrical, plumbing: seismic bracing for lines, conduit, piping, ductwork and water heaters; anchor roof-mounted equipment through a continuous load path; elevate or dry floodproof vulnerable components such as controls, panels, HVAC and machinery rooms, generators and fuel tanks, or use submersible-rated equipment where wiring can’t be elevated; install switches, circuit isolation, quick connects, camlocks, transfer switches and panels for backup power.
• Pipes: joint restraints, flexible connections or more ductile pipe; continuous lining or encasement; shut-off valves to isolate damaged underground sections.
• Water and wastewater: replace inundated pumps with submersible or inline pumps; elevate sewer access covers to the hydraulic grade line or use watertight frames and covers; seal well casings or raise well heads; buttress raw water intakes.
• Electric power: looped or redundant service to critical facilities (not grid capacity expansion); surge suppressors and lightning arrestors; elevate pad transformers above base flood elevation; support pole transformers with multiple poles; replace poles with higher-rated poles (preferably two classes stronger) with guys and anchors; cross-brace H-frame poles; add guy-wires.
• Storage tanks: anchor or stiffen base connections; install self-initiating disconnects and shut-off valves.

Equipment specifications, elevation or floodproofing designs, pole class ratings, and drawings for bracing, anchoring or redundant service.

• Bridges: replace with low-water crossings where traffic counts are low; install cables to keep bridges on piers or abutments in floods or earthquakes; install girder and deck uplift tie-downs; install longitudinal peaked stone toe protection with planting upstream of a failed abutment, or similar solutions such as engineered logjams, log vanes or bendway weirs.
• Marine pier ramps: if attached to decking, install open or floating decking with uplift-resistant tie-downs and fasteners.
• Roads and railways: where shoulders are prone to overflow, stabilize shoulders and embankments with geotextile fabric (erosion control blankets or turf reinforcement mats) and revetments.
• Roads: use geotextile drainage blankets between the pavement section and subbase.
• Signs: replace panels and supports with a stronger system, including multiple posts and stronger panels and fasteners.

Traffic counts for low-water crossing proposals, bridge and roadway designs, and specifications for the strengthened components.

• PA and EHP staff decide whether a hydrologic and hydraulic study is needed. You must submit one when the facility is in a special flood hazard area; there may be adverse floodplain impacts; there may be impacts to listed species, critical habitat or essential fish habitat; or it’s needed to show Clean Water Act compliance.
• Replacement structures must be considered as part of the total drainage system, using existing local drainage criteria for sizing.
• Erosion control can include headwalls, wingwalls, flared aprons, energy dissipators, gabions, rip rap, concrete, crushed rock, sheet piling, geotextile fabric (for roads paved before the event), and vegetated measures such as live fascines, vegetated geogrids, live crib walls, brush mattresses and root wads.
• Culverts may be realigned or relocated, have discharges extended beyond the embankment toe, and get debris barriers, fins or barrier risers. A relief culvert can provide an alternate flow path.

A hydrologic and hydraulic (H&H) study when required; local drainage criteria used for sizing; and designs for entrance and exit structures, erosion protection or realignment.

• Measures in Appendix J are cost-effective if they do not exceed 100 percent of the eligible repair cost, before any insurance reductions.
• They must meet all eligibility requirements in the Hazard Mitigation section of Chapter 8.
• Where codes or standards require the measure, it is completed as part of the PA repair project with no additional cost-effectiveness evaluation. Resilience beyond the code requirement is PA mitigation.
• All measures must comply with EHP laws, regulations and executive orders.

The eligible repair cost (before insurance reductions), the mitigation measure’s cost, a description showing it matches a measure in Appendix J, and EHP compliance information.