Flood Recovery Booklet


United States Department of the Interior

NATIONAL PARK SERVICE
P.O. Box 37127
Washington D.C. 20013-7127

AFTER THE FLOOD: Emergency Stabilization and Conservation Measures

After the flood waters begin to recede, the focus of relief efforts becomes returning things to normal. During this phase, many historic structures and properties are needlessly lost and damaged through hasty clean-up procedures. The best way to help a historic district, property, or structure prevent additional damage and maintain its integrity and character during these times of duress is with the use of proper caution and concern.

While the water is receding, plan the future steps to rehabilitation and restoration carefully. Each decision made today affects future decisions which will need to be made tomorrow. The following areas of concern should be addressed during planning.

PERSONAL SAFETY: The First Priority

  1. Return to the area only after it has been declared safe by local emergency management officials. Follow all emergency rules, laws and regulations.
  2. Identify potential hazards and solicit expert advice and assistance to minimize the dangers. Report and stay clear from loose power lines or damaged utilities.
  3. Turn off all utilities associated with the historic property to prevent further damage and minimize future hazards.

DOCUMENTATION: Developing a Condition Assessment Report

  1. Prepare a visual record showing the scope of the disaster and the damage to the historic fabric. This is best done through annotated photographs, and narrated videotape taken before the cleanup actually begins.
  2. Create an inventory of found items, dislodged architectural features, decorative fragments, furnishings, collections, etc. DO NOT THROW AWAY MATERIALS AT WILL. Many items may prove their value as the surrounding restoration or rehabilitation projects proceed.
  3. Use the gathered information to have a team of preservation professionals develop a prioritized plan of stabilization, repair, and restoration.

STRUCTURAL STABILIZATION: Temporary Measures

  1. Identify potential deficiencies and provide temporary shoring to protect life, property, and belongings while the water levels are receding. Successful shoring can be accomplished without increasing the damage to the historic features or materials. All shoring measures should be planned with the assistance of qualified structural engineers or contractors.
  2. Clean and repair the structure's roof and roof drainage system in order to protect the building from future storm damage.

DRYING OUT: Natural Ventilation and Time

  1. Carefully remove trapped mud and collected water/storm debris as water recedes. Do not unnecessarily damage covered historic finishes or materials.
  2. Remove standing water and water-logged furnishings and debris that maintain a source of moisture within the structure.
  3. Remove residual moisture in a gradual and controlled process through natural ventilation. Do not use mechanical dehumidification which may cause additional damage.
  4. Allow plaster to dry gradually, avoiding cracking and separation of layers.

    Forced drying through the use of dehumidifiers and heaters may draw excessive moisture through the plaster leading to excessive expansion, cracking, and powdering of the finished surface.

    Carefully remove all flood soaked Gypsum Wall Board. It is a porous material which degrades under extreme moisture trapping fungus and bacteria that pose health hazards.

  5. Allow wood to air dry gradually. Promote even drying through proper ventilation. In most cases, swelling and warping of the solid wood, flooring and framing, will be minimal and decrease as the wood dries. Laminate wood surfaces may experience separation and warping caused by the uneven drying of the layers.

    Forced drying through the use of dehumidifiers and heaters will cause uneven drying, resulting in the cupping, warping, and checking of the wood.

    Monitor the wood. If wood elements remain damp after the other moisture problems have subsided, fungus and/or rot and decay may develop.

HOUSEKEEPING MAINTENANCE Initial Cleaning and Repair

  1. Rinse remaining mud, dirt and flood debris from all surfaces with freshwater. Do not use high pressure water on historic materials. Use extreme care and caution around decorative features and damaged elements.

This information was produced and compiled by the Preservation Assistance Division, National Park Service, Washington, DC. (202) 343-9578.

rev. January 17, 1995