In what the civil engineers gtroup termed "the most significant change" to the 7-22 standard's flood load provisions since the inception of ASCE 7. the new supplement ties flood hazard mitigation to a
structure’s risk level, and sets the hazard area for most risk
categories to the 500-year floodplain for determining flood loads.
A realigned, 2.5-mile segment of Highway 101 north of San Francisco opened this month, a major step in widening 16 miles of the heavily traveled Marin-Sonoma Narrows.
Following a new analysis that examined the damage and flood impacts of Hurricane Harvey, Houston’s Dept. of Public Works is recommending that all new structures in the city’s 100- and 500-year floodplains be elevated to 2 ft above the 500-year flood elevation to avoid such damage in the future.