September 2007, Vol. 19, No.9

Small Communities

Surviving Disastrous Weather in Small Utilities

James C. Pyne, Steven Berkowitz, and Dave Clark

 Nothing can take the place of disaster planning and preparation. In real estate, they say that the three most important factors in selling a property are “location, location, and location.” In disaster recovery, the most important factors are “preparation, preparation, and preparation.”

Disasters are like fingerprints. No two will ever be the same. (Also, like babies, they most often seem to come at night!) The Saffir–Simpson Hurricane Potential Scale classifies hurricanes into five categories based on central pressure and sustained wind speed. However, this categorization can often be misleading, especially when the most lethal aspect of a particular storm is not its winds but storm surge or inland flooding. Never underestimate the destructive power of even a minor hurricane.

You never can predict what people will do before and after a disaster. Particularly in areas prone to frequent disasters, people become complacent or frustrated. If they choose to stay when a voluntary evacuation is recommended and the disaster is relatively mild, they will be emboldened to stay the next time. Those who act out of frustration usually do so because when they did evacuate, they were not allowed to return to their homes when they thought it was appropriate. Their refrain is, “Next time, I’m going to stay.” These attitudes put more people in harm’s way.

In smaller cities and towns with central utilities, those who choose to stay and whose homes survive in a habitable condition expect their utilities to be restored as soon as possible. Unfortunately, no matter how often they are told not to use the public water supply until given the “all clear,” some customers still will turn on the faucet as soon as they have water. These actions ultimately may require pulling every water meter from the system and only reinstalling them after the water in that area is safe to drink and the wastewater can be treated. This procedure adds considerable cost to the service restoration process and significantly extends the total recovery time. To combat residents’ urge to say “next time,” make it clear that if they choose to stay, they will be without utilities for several days, at a minimum.

For smaller communities with residences and businesses not served by central water and wastewater utilities, the susceptibility of individual and community onsite water and wastewater systems to disaster depends on what type of system is in place. In general, the simpler the system, the less likely it is to be affected.

Experience has shown that a properly sited subsurface septic system generally survives flooding quite well. The soils may temporarily become supersaturated, which prevents proper operation until the surface water and groundwater subside. Very little damage to the systems or contamination from the systems has been observed due solely to flooding. Also, it is not prudent to pump out a septic system immediately after a flood. Buoyancy issues and structural failure potential are highest when the ground surrounding the tank is fully saturated. The accessibility to land application sites and the capacity of wastewater treatment plants to receive wastewater also are severely restricted during and after a major flood event in a disaster impact area.

Exposed components add another dimension to the potential for problems. Access manholes, either to tanks or conventional gravity collection sewers, facilitate massive siltation and sand inflow in addition to the omnipresence of severe hydraulic overloading of the system. Pump systems also are susceptible to control system damage, which renders them inoperable and causes overflow to the surface. While many pump systems can be brought back in service after drying out, most of their electrical components eventually must be replaced.

Power outages and homeowners’ responses to them also have short- and long-term implications for power-dependent onsite systems. This problem is compounded when potable water under pressure is available, but power is not. Homeowners also have become quite resourceful in devising standby power generation and hook-up schemes. An extension cord run from a portable generator to operate a wastewater pump could create a bigger problem than it solves if the motor is started and the cord or power supply is incompatible with the pump’s starting and running requirements.

One of the greatest impacts after a disaster can be damage to onsite wastewater system components on waterfront properties. Tanks may be overwashed and contents discharged, or the tanks can become shifted, disconnected, and filled with sand or silt. When the septic tanks or, more commonly, the drainfields have eroded, there is often insufficient area remaining to repair the systems in accordance with local codes. Exposed tanks also can be a hazard to recovery workers or people returning to their properties.

In general, municipalities must develop a disaster plan that brings together all agencies that can assist or have an impact on the utility and residents. This plan must include options for all contingencies and contain contact lists for all employees, other nearby utilities, state regulatory agencies, and vendors. Every time any of these contacts or individuals change status, the list must be updated. In addition, relevant local, state, and federal regulations must be on file and reviewed periodically to maintain familiarity with them.

Part of any small utility’s predisaster planning must include identifying the vulnerable points in their systems and taking action not only to protect these locations but also to isolate them if they pose a threat to the system as a whole. Since Sept. 11, much emphasis has been placed upon vulnerability analyses and guarding against terrorist attacks on utilities. However, utilities are much more likely to suffer catastrophic damage from a flood, hurricane, earthquake, or tornado than from terrorism.

Preparation encompasses the entire range of planning, stockpiling needed resources, entering into contingency contracts for supplies and labor for the recovery efforts, and maintaining liaisons with state and federal disaster recovery agencies. Since billing and collection efforts may be seriously affected by a disaster, a line of credit may be necessary to maintain operations.

Know your systems, especially their weak points. Prepare for the worst. Shut down those vulnerable sections, regularly test generators, top off fuel tanks, and notify the public that services, by design or disaster, will be unavailable for an unforeseeable period of time. Know the Federal Emergency Management Agency’s regulations and adhere to them. Work with other local agencies to maximize preparedness and better ensure recovery. Read and interpret the National Weather Service’s publications.

We owe it to our customers to educate ourselves to these realities. Don’t wonder if we will get hit by one or more disasters. Only wonder when they will come and how bad they will be!

James C. Pyne is chief of the Small Communities Division at Hampton Roads Sanitation District (Virginia Beach, Va.), Steven Berkowitz is engineering team leader for the onsite wastewater section of the North Carolina Division of Environmental Health (Raleigh), and Dave Clark is public works director for the Town of Nags Head, N.C.

James C. Pyne is chief of the Small Communities Division at Hampton Roads Sanitation District (Virginia Beach, Va.), Steven Berkowitz is engineering team leader for the onsite wastewater section of the North Carolina Division of Environmental Health (Raleigh), and Dave Clark is public works director for the Town of Nags Head, N.C.