At times of melting snows, hurricanes, or heavy rains, a river may receive more water than its channel can normally contain, and may spill over the banks onto wetlands and fields known as flood plains. By studying a river's past history, geologists can obtain a basic idea of its general behavior, including how often floods of various magnitudes can be expected and in what areas.

Flood plain ordinances designate the floodway zone as how far the flood waters will reach in a certain number of years. There are 2 flood plain zones, the 10-year and the 50-year, and what the Cacapon River residents underwent several years ago was flooding in the 100-year flood zone.

Protecting Your Service Equipment

Electric wiring and meters, telephone cables, water and sewer lines and drains, gas lines, specific tanks, heating and cooling equipment, appliances, and other service equipment need to be protected against flooding.

Protecting this equipment involves much less time, money and effort than trying to protect your whole house. You should protect your household equipment immediately, whether or not you plan to do more extensive work. Several methods can be used to protect your service equipment.

Anchoring your storage tanks

Anchors and tie-downs are two best ways of protect­ing your fuel storage tanks, whether they are above ground but not raised above flood level; or stored below the ground. Both types of tanks are extremely vulnerable to floatation. Flood waters act directly on above-ground tanks, and below-ground tanks can be forced out of the ground by the buoyancy force of saturated soils. When either type of tank is displaced, its connections can be severed and the escaping fuel can cause hazardous damage to humans and to the environment.

Above-ground tanks can be anchored with metal straps or cables that cross over the tank and connect to ground anchors. The length and type of ground anchor you need depends largely on the type of soil at the site.

Ground anchors can also be used for below-ground tanks. This method involves excavating the soil above the tank, placing steel I-beams across it and connecting them to ground anchors. Another alternative is to excavate down to the tank and pour a concrete slab on top. It is most important that flexible connections be used between the anchored tanks and the supply lines. Also, vent and filler tubes must extend above the flood level. Raising equipment

Household service equipment can be elevated to a floor above the flood level, placed on pedestals of brick or concrete, or put on cantilevered platforms extending from the house.

Protecting with walls

If you cannot move your service equipment, they should be protected with floodwalls and shields or other methods to prevent water from damaging them.

TIP: If you have adequate warning of an impending flood, fill up your storage fuel tanks to the top. A full tank will be less susceptible to corrosion from accumulated moisture and will be heavier and better able to resist buoyancy

Protecting Your Whole House

Relocating the house

Moving your home out of the flood plain provides the greatest protection. This involves lifting a house off its foundation, placing it on a heavy-duty flatbed trailer, hauling it to a new location, and placing it onto a new foundation.

The major considerations involved are 1. condition of the house, 2. its design and shape and 3. the route be­tween the old and new sites. Obviously if the house is not in excellent structural condition it does not make sense to move it in one piece. However, it is possible to cut a building into parts and move each part separately. If you want to move your house just a short distance, say to higher ground on the same piece of property, the "route" may not be a problem.

Building protective levees and floodwalls

Levees and floodwalls are barriers that hold back flood waters but they differ in their design and construction, appearance and application.

Floodwalls are manufactured structures that generally are more obtrusively visible than levees.

Levees are embankments of compacted soil that have the advantage of blending into the landscape and being less of an eyesore. However, they require more land than floodwalls, and they must not violate any restrictions if you live within a floodway.

Some things to think about when using these techniques are:

1) What height should the wall or levee be? It should be high enough to hold back potential floods.

2) If a flood should "overtop" the barrier, there must also be a method for removing water that comes over the top. 3) Will either barrier block a view or access to the river?

Wet floodproofing your house

Wet floodproofing is a method that relies on the walls of the house to hold the water out while allowing flood waters to enter and exit the enclosed areas of your house through wall openings. Literally, the river flows through your house. This means that all construction and finishing material in the house that might possibly be flooded must be resistant to damage caused by water. The most important aspect of this technique is that it equalizes the effects of hydrostatic pressure, which is the most destruc­tive factor in a flood. Hydrostatic pressure is the force the flood water will place on or under walls and floors. More pressure on one side than the other will cause a wall to collapse or a floor to buckle.

The following things should be considered:

· ensuring that flood waters enter and exit the house

· ensuring that flood waters inside the house rise and fall at the same rate as flood waters outside (hydrostatic pressure)

· protecting the areas of the house that are below the flood level from damage caused by contact with flood waters

· protecting service equipment

· relocating any personal belongings that would be damaged by flood waters.

Another consideration is the post-flood cleanup. Flood waters are rarely clean. They usually carry sedi­ment, debris and corrosive or hazardous materials such as solvent, oil, sewage, pesticides, fertilizers and other chemicals.

Dry floodproofing your house

Unlike wet floodproofing, dry floodproofing involves completely sealing the exterior walls of the house to prevent the entry of floodwaters. Openings below the flood level should be sealed, protecting the interior of the house from seepage, and protecting service equipment such as furnaces, both inside and outside. In addition, a special­ized drainage system must be installed.

Dry floodproofing is practical only for houses with walls constructed of flood-resistant material and only where expected flood depths are low, no more than two to three feet.

A major consideration in dry floodproofing your house involves preparing the house in advance of a flood by manually closing doorways and windows and other open­ings. (So it is not appropriate for part-time owners or weekenders who cannot do this work before a flood.)

Elevating your house:

Elevating a house to prevent flood waters from reaching living areas is another technique that will protect your home. The goal of this process is to raise the lowest floor above the highest level a flood can reach. This can be done by elevating the entire house onto walls or stilts, or by constructing a new, elevated floor within the house or building a second story and moving the living area to the upper level.

A Special Note - backflow valves

Flooding can often inundate and overload sanitary sewer systems and combined sanitary/storm sewer sys­tems. The best solution to this problem is usually to retrofit the system by installing backflow valves. The installation of backflow valves and other plumbing modifications is regulated by state building codes. A plumber or contractor licensed to work in your area will know about the retrofitting code requirements.

Details on this matter are available in Federal Emer­gency Management Agency's (FEMA) book "Homeowner's Guide to Retrofitting." The book includes chapters titled Financial Assistance for Retrofitting. Keynoted Definitions, and a useful Decision Making Matrix that will help you evaluate the advantages and disadvantages of different techniques, and several informative appendices with a Bibliography and Sources of more in

SEE ALSO:

Morgan County Floodplain Ordinance - Printed on a separate sheet, this information will give you the regulations if you intend to build in the floodplain.

Where to get more information/Help - Printed on a separate sheet you will find the web site for FEMA.