What does design high water refer to?

Design high water refers to the flood stage adopted for drainage structures. This term represents the anticipated height of water during extreme weather events, which can include factors like heavy rainfall, snowmelt, or storm surges. It is crucial for engineers and planners to know this elevation in order to properly design drainage systems, levees, and flood control measures that can effectively manage water flow and reduce the risks of flooding to infrastructure and communities.

By establishing this elevation, engineers can ensure that structures are built above potential flood levels, thereby minimizing damage and enhancing public safety. This concept is essential not only for effectively managing stormwater but also for compliance with regulations and standards set forth by local and federal authorities.

The other choices do not capture the essence of "design high water" as accurately. The average tide crest may not reflect extreme weather conditions, the lowest flooding event does not provide a comprehensive safety margin, and maximum recorded rainfall is only one aspect of flooding that does not account for other variables impacting water levels.