Feb 2012

Flood Protection

Recent studies have shown that anywhere from 10 to 25% of facilities can experience flooding. Flood maps can give an indication of the flood exposure for a facility. However, there could be errors in these maps or the maps could be outdated. If changes have occurred within a flood plain since the last study, then this could change the extent of flooding. Additionally, surface water from heavy rains could affect a facility outside of areas listed as flood prone on Federal Emergency Management Agency (FEMA) flood maps. Also, city drainage systems are typically not sized to handle heavy rains due to the expense involved.

If your facility is determined to be prone to flooding, you might wonder what can be done to protect it. The answer to this question varies, depending on the expected frequency of flooding and the potential impact to your facility. Facilities with a lower frequency or expected impact can likely be protected with a good Flood Emergency Response Plan (FERP). However, facilities with a higher frequency or greater impact would be best protected with physical protection.

This physical protection will also vary, based on the facility and the potential exposure. A well maintained levee may be the answer for some facilities. Please note that levees must be maintained properly to ensure that they will function as designed in the event of a flood. The maintenance of these levees is controlled by a levee management authority and not by the plant. Thus, your facility would not have much control over this maintenance.

To ensure that levees will protect areas from flooding, they must be accredited by FEMA. To do this, local governments or other responsible parties must certify that a levee can withstand a 100 year flood event (1% chance of this flood level being reached in any given year). Some levees are so deteriorated that it would cost tens of millions of dollars to improve the levees to properly protect some areas. Unaccredited levees are more prone to failure. If your property is in an area where it is protected by a levee that has lost it accreditation, then your facility is considered to be more prone to flooding. Further information regarding the lack of levee reliability is available in a USA Today article titled, FEMA: Hundreds of Levees No Longer Reliable, at the following link: http://www.usatoday.com/news/nation/2010-09-09-levees_N.htm.

Other options include physical protection directly at your site. This protection will vary, based on whether or not polluted flood waters could be allowed in the buildings. Extensive cleanup and restoration would be needed for areas affected by flooding. Raising important equipment, utilities or paper above the expected level of flood waters would help. However, there are means of keeping water out.

The best way to keep water out of your facility would be to provide physical barriers at all openings. Doorways are often provided with barriers. However, other openings are often missed. This includes, but is not limited to: openings/cracks in walls, storm water drains, and electrical conduit. The barriers provided should be able to hold the expected floodwaters. These barriers should be tested and approved for this use. FM Global has approved pedestrian doors and flood plank barriers manufactured by PS Doors Inc. More information on these doors is available on their website http://www.psdoors.com/flood.php.

If you would like help determining the level of flood protection you should have for your facility, please contact Risk Logic for assistance.