Bob Crossen is managing editor for W&WD and iWWD. Crossen can be reached at [email protected].
Earlier this year an earthquake struck California and it got me thinking: Are there seismic design standards for water and wastewater pipe? For many years, buildings in areas where seismic activity is common, notably California, have had to adhere to construction codes to ensure buildings stay upright during an earthquake. In the late 1990s, the International Building Code added three factors—seismic risk, occupancy type and soil conditions at the site—to take into account with new construction.
Similarly, the U.S. Department of Transportation Federal Highway Administration has a manual for seismic design of bridges, flyovers and overpasses. Although it was not due to a seismic event, one does not need to look further than the bridge collapse at Florida Intl. University earlier this year to get an understanding of the damage a collapse can cause.
But when it comes to seismic design for water infrastructure, pipe in particular, there are no similar standards of design required. The more associations and agencies I called, the more I learned that that these standards are lacking, despite the record of damage to pipe related to seismic events. The Water Research Foundation published a report in 2012 that aimed to determine how much pipe was damaged in three seismic events from 2010 to 2012. While the study lacks descriptions of the extent of the damage to the different pipe materials, it does present a nasty picture of what an earthquake can do to water infrastructure.
For all the discussion of resilience in disasters—tornadoes, flooding, hurricanes, etc.—it seems like an oversight that resilience for earthquakes has not been created yet.
However, there is some hope on the horizon. The American Society for Civil Engineers is working on a Manual for Purpose on seismic design for pipe infrastructure, and has sought input from major pipe associations in the industry. I’m looking forward to seeing how that shakes out, and when it is released, I hope to follow up on seismic design for pipe.
Perhaps there will be more detailed research on the extent of the damage to pipe in these events, too.
