Floods The American Southwest has in late June, July, and August Monsoons.  Monsoons are rainstorms that can dump up to 3 or more inches of rain in an hour, and this rain produces runoff that can floor streets, buildings, lawns, etc..  Most of this water is eventually absorbed into the ground to replenish the aquifers, but can cause much damage before this happens. The BorderTransportationSystem is directly in the path of these Monsoon rains, and therefore will need protection against floods and the debris that is generally associated with the flooding.  The systems bridges have to stop illegal border crossings, and therefore will be a location for backed up flood waters and debris collection.  Sensors and water level meters are available and have been in service for years, and these can be used to detect problems.  Maintenance access and crews will have to be assigned to each possible debris area, and this will during the Monsoon season cost money.  Index of ... Application of High-Tech Bridge Safety Monitoring System on monitoring results - *.PDF How Does a U.S. Geological Survey Streamgage Work? USGS Current Water Data for Arizona USGS Current Water Data for California USGS Current Water Data for New Mexico USGS Water Data for Texas USGS Current Water Data for Texas