Recalculate 10 to 100 Year US Storm Rainfall Contours

Focus Area

Climate Change


Air Quality, Environmental Process






1-2 years

Research Idea Scope

Recalculate contours for 10, 25, 50, 100 year storms for 24 hour rainfall amounts across the US based on down scaled global climate model output data.  Engineers and infrastructure planners need a new basis for stormwater calcs. Existing contours for 24 hour rainfall in the 10, 25, 50, 100 year rainfall events were developed decades ago based on historical TP40 statistical methods which are no longer valid for planning and designing tomorrow’s infrastructure.  Using a combination of MORE RECENT rainfall records, model output from climate models, and other factors, new contours for 24 hour rainfall probabilities are needed for designing and planning for infrastructure with a 10 year lifespan, 25 year lifespan, 50 year lifespan and beyond.

Urgency and Payoff

Infrastructure dollars spent today to design and build tomorrow’s infrastructure will not get washed away due to heavier, more intense rain events, predicted for many parts of the country.

Suggested By

Ray Sirois, Wright-Pierce