An Introduction to Flood Protection: Early Warning Flood Forecasting and Properly Meeting the Owner’s Needs

The final installation of our series of posts related to An Introduction to Flood Protection by Doug Coenen and Ray Drexler, examines early warning flood forecasting and the critical steps that need to be accomplished among team members in order to meet an owner’s needs

Early Warning Flood Forecasting

The Early Warning Flood Forecasting System reviews real-time rain forecasts from the National Weather Service (NWS) to provide early warning of approaching storms. The system can be a simple weather alert tied to the NWS alerts or a more complex dynamic model that starts processing the forecast to predict the potential of flooding. The Early Warning Flood Forecasting System is coupled with an action protocol developed using the engineering parameters of the system to document what actions are to be taken when certain predetermined thresholds are met.

The connection to the NWS rain forecast provides dynamic planning capabilities to the owner. Knowing what is currently predicted to result can alter decisions well in advance of the storm. The Early Warning Flood Forecasting system continues to update itself as the NWS updates their rainfall forecasting, allowing the owner to have continuous up-to-date information on future flood risk. This aids in determining which flood protection protocols to activate, modify, or cancel for staff/site safety as new information becomes available.

An important element of any active flood protection system is the linkage of a flood warning system to a documented engineering protocol that stipulates what actions to take when certain flood and rainfall thresholds are met. The flood implementation protocol must be a documented and practiced action plan that takes the guessing out of the system implementation. This allows staff to be prepared and act without waiting for approvals and decisions to be made, eliminating some potential for human error in getting the system in place in time to protect the facilities.

The Early Warning Flood Forecast System development takes into consideration the amount of time needed to implement the flood protection system, the ability to keep areas of important access open for as long as practical, and it also provides the protocol when it is safe to retract the flood protection system. When loss of normal operations can impact effectiveness and critical activities, the Early Warning Flood Forecast System can be a very important part of the flood protection system.

Teaming to Meet the Owner’s Needs

The flood protection team’s design is for the owner and must meet the owner’s special needs. This requires that the team spend time with the owner to explain what the team knows and what the owner should consider. Every critical team member should be included in discussions so that everyone is on the same page, or understands why positions may differ. A large and diverse group beyond the owner and design team—FEMA consultants, FEMA, DEM, local AHJ, public or private funding entities, and others—must be included so that everyone is able to voice their concerns. The design team needs to listen to all these parties. It is key for the team to develop an understanding of how the owner operates, what their needs are, and their capabilities/limitations to operate the flood protection improvements. The team does not work in a vacuum. The design involves critical operational considerations. The team must integrate the owner’s staff to gain an understanding of how potential mitigation solutions impact existing operations and costs to ensure that the optimal solution is determined.

The team must also gauge intent and level of risk to determine feasible alternatives. Finally, the team must present alternative solutions to help the owner understand the impacts, then the solution will evolve to address those critical issues by working closely with the owner’s operations. These solutions often require knowledge and action by the owner’s staff.

The level of owner involvement in the design process and how they will interact with the design team needs to be determined during the scoping phase. It is critical to determine if the owner wants to be involved in the day-to-day decisions (active) or only in setting the overall objectives (passive) with the design team presenting potential solutions before refining the desired option. Also, does the owner have a FEMA, DEM, or other funding agency consultant that needs to be included in the decision process, so the design team is aware of the financial and/or regulatory reviews/issues?

The next important scoping decision is who will lead the project. Frequently the civil/structural engineer is retained as the prime design consultant, based on their flood mitigation experience. Some owners expect an architect to prime the project. If the design team is open minded and collaborative this also works well. Most larger flood mitigation projects require an architect, a code consultant, MEP engineers, civil and structural engineers, surveyor, building enclosure specialist, hydraulics and hydrology specialist, and some require other specialists such as FEMA or vibration consultants.

For more complex projects a construction contractor should be onboard early to provide constructability reviews and cost consulting. Occasionally, the owner may add other “team members” such as a key tenant representative that provides input and makes demands with no authority to fund or approve ideas. It is always important to understand the role and authority of all team members and how to interface with them so that the project is properly scoped and meaningful and constructive communication occurs in a timely manner.