By Nathaniel Montague
It’s no secret that natural disasters are getting worse—both in frequency and severity. It seems every week there is a breaking story from some corner of the globe sharing news of a “once-in-a-generation” fire, tornado, or storm. Flood events have no doubt contributed to this phenomenon significantly. Though disasters of all kinds have become more frequent over the last 100 years, the rise in the number of flood reports has far outpaced that of any other type of natural disaster.
Between 1920 and 1972, only 329 floods were reported worldwide. In the following 50 years (1973-2022), the tally jumps to 5,476—with 71% of them (3,897) occurring between 2000 and 2022. Floods are now a near-daily occurrence for Americans—with no “high season” or uniquely high-risk areas, according to the Pew Trusts. We must shift away from the traditional mindset that a once-in-100-year flood happens only once every 100 years. Now, wherever it rains, it floods.
That means facility managers can no longer count on their location to save them from the consequences of these natural hazards. Now, they must look to their facilities’ designs to mitigate floodwater impact, and they can start by incorporating this growing risk into their facilities’ risk assessments.
A Familiar Process
To adequately assess flood risk in today’s fast-changing environment, operators should move past compliance-led programs, focusing instead on a holistic, risk-management-based approach. Conducting this process for floods may be foreign to operators in traditionally low-risk areas, but—luckily—the steps mirror best practices for other natural disaster assessments:
1. Develop an understanding of contributing factors. Flood mapping begins with research. Facility managers may wish to collect data related to the type of flooding in their area, water height, flow velocity, rise speed, duration, and the percent annual chance (“return period”) of flooding events. They will also need to dive into the topological, meteorological, and other specifics of the facility’s location as well as the history of the building and local area itself to ensure it’s up to the latest building codes. These factors can all influence flow velocity, hydrostatic loads, the presence of debris, and more.
FEMA’s National Risk Index website and Flood Assessment Structure Tool (FAST) can help operators get started, but—for those that have not assessed flood risk before—working alongside a third party with expertise in the subject may be helpful.
2. Map out threat timelines. Floods are highly variable events and can last from minutes (flash flooding) to hours, days, or weeks. Using the above information, teams should map out likely timelines for their areas, from the first warning to the emergency’s end.
Understanding these timelines can help managers determine what mitigation actions staff will be likely to have time to complete during different phases of the incident.
3. Identify potential outcomes. The facility’s risk factors and the region’s likely timelines should guide the team’s initial assessment of the potential outcomes. Teams should consider the impact on property, equipment, raw materials, finished products, technology systems, and any other assets in the facility.
It’s important that this step is carried out by a cross-functional team with diverse experiences. The team should assess everything from water ingress mechanisms, flood defense effectiveness, and equipment vulnerability to business considerations like the impact of downtime or lost materials. The team should also consider community and worker health and safety issues that may accompany floodwaters in the building.
4. Dive deeper into the most serious scenarios. Teams can now home in on the possibilities they find most concerning, whether due to their relative severity or likelihood. To do so, managers should note:
- Any vulnerabilities in the facility’s fixed plant and piping, electrical control and instrumentation systems, utilities, and shutdown systems that can contribute to or exacerbate the scenario.
- The effectiveness and reliability of the facility’s current flood barriers.
- Any cliff edge effects that may play a part in the scenario.
- The human factors that may contribute to the situation or impact the execution of emergency response plans.
5. Develop—or revise—response plans. Now the team is ready to use all the information they’ve compiled to design risk-led response plans. The final version should include both emergency response protocols for different types of flood incidents and plans to proactively remediate existing hazards that exacerbate different scenarios. While it is important to ensure these plans meet any local or industry-specific standards, actions should be guided by the findings of the holistic profile developed above.
6. Execute. This is perhaps the most difficult step for many operators, regardless of the risk category they’re addressing. Even the best-laid plans don’t help when an emergency comes knocking if no one knows how to execute them. Similarly, knowing about a faulty mechanism is useless if you don’t take the time to fix it before the flood begins. Facilities that are serious about mitigating the risk of floods to their operations should invest in training, improvements, and other supports that ensure their hard work is put to use.
7. Keep at it. Finally, facility managers must view flood mapping as an ongoing process. It cannot be a one-and-done endeavor because threats evolve by the day. Managers should make flood mapping a recurring process to ensure plans stay up to date.
Preparing Today For Tomorrow’s Floods
Unfortunately, facilities that may not have been at risk when they were built are now facing the threat of flood damage, from coast to coast and around the world. And, like it or not, the responsibility for protecting facilities and surrounding areas from the consequences of these fast-moving disasters will fall to facility managers and corporations before guidance on the subject reaches the desks of legislators and regulators.
However, this lack of guidance also presents an opportunity for forward-looking businesses and facility managers to design flood protections that work for their operations, communities, workers, and business objectives. Even more compelling, it’s an opportunity to invest thoughtfully in the business’ future, ensuring you’re ready when—not if—a flood touches your operations.
Montague is a Program Manager at ABS Group with over 13 years of experience in developing multi-hazard studies and flood-related risk model development. Nathan serves as the Program Area Manager under the Compass PTS JV for FEMA’s Natural Hazard Risk Assessment Program, where he is part of a team that created and continues to maintain the National Risk Index and updates Hazus software data, methodology, technical documentation, and training materials. Under FEMA’s Building Science Branch, he led a team to produce the Building Codes Save study which quantifies the return on investment and nationwide economic losses avoided by adopting disaster-resilient building codes.