It is vital to recognize that even after the implementation of non-structural flood mitigation measures residual flood risk will remain. It is of paramount importance to make plans to deal with flood events and their aftermath. This involves multiple activities which can be included as part of a flood emergency plan. In this section there is an overview of the elements central to emergency planning.
Identifying existing internal organizations
All countries possess existing institutions and organizations that, if coordinated, may be mobilized to meet individual emergencies. The purpose of the emergency plan is to identify these institutions prior to the emergency in order to:
- Identify roles and responsibilities.
- Identify command structures.
- Facilitate inter-agency cooperation.
The preparation of the emergency plan will help to identify barriers to cooperation, including authority structure and finance, which need to be resolved before flooding occurs.
Identifying appropriate external agencies
Some flooding events may be addressed using existing national resources but many countries do not have sufficient physical and human resources to address regional and national emergencies. It would then be appropriate to invite the assistance of external agencies.
The presence of international agencies may, however, overwhelm the host government with the risk that the latter may lose control of the relief effort. This, in turn, can result in the deskilling of local people who may feel it necessary to defer to the external agencies. It should also be recognized that the objectives of external agencies may conflict with those of internal agencies: for example, to ‘showcase’ their charity in high profile emergencies. Managing these agencies is both difficult and time consuming and may require considerable diplomacy.
The emergency plan should therefore contain detailed policies, identifying the roles and responsibilities and restrictions on invited agencies.
Actions taken before a flood arrives can significantly reduce the loss of life and the amount of damage suffered. Pre-warning and evacuation planning should therefore be part of an emergency plan. It follows that an early warning system (see Section 4.9) is a central requirement for damage avoidance. Local flood emergency planning could involve, for example, the installation of temporary flood barriers, or the removal of zoo animals (as in the Cologne case study elsewhere in this volume). Deployment of some building design features, as described in Chapter 3, may also be dependent on warnings being issued.
It is necessary to mobilize personnel and machinery, where available, to protect infrastructure (such as dikes, levees and retention basins); to remove individuals from facilities at risk (such as hospitals, schools, industrial sites, bridges, or individual houses); and to prevent landslides and riverbank erosion. Strengthening and rehabilitation of existing structures and flood-proofing measures can also protect critical infrastructure. Such measures may include sandbagging or establishing temporary earth, wooden or other flood barriers, including mobile flood barriers (WMO 2011).
Flood emergency preparedness activities
To coordinate emergency procedures, a flood management unit (FMU) needs to be set up. Representatives from the local community should be included as members. The FMU will be responsible for developing a business and government continuity plan (BGCP) and for coordinating emergency procedures in a secure flood free location, as identified in the evacuation plan. The FMU can also be organized to serve as the local representative, focal point or community partner for wider river-basin level planning. Government continuity planning requires the community to effectively participate throughout the planning process. Participatory planning for emergency situations can help build trust and confidence among stakeholders, enhance cooperation, facilitate information sharing and encourage regular communication (WMO 2011).
At a household level a number of strategies can be adopted which will reduce damage as a result of flooding. Including the following:
- The identification of household escape routes
- Installation of temporary flood proofing
- The identification of elevated buildings (or even mature trees) that can be used as safe havens
- The moving of property to higher levels
- The storing of emergency provisions
- The use of non-flood impacted communications such as radios, mobile phones or even prearranged signals in order to share information
- The removal of vehicles from the area: their use in the post-flood situation is invaluable.
Emergency water supplies and sanitation
The flooding will have destroyed existing water supplies and sanitation infrastructure, where applicable; any overflow of sewage will also have polluted water supplies. The emergency plan should therefore identify alternative water supplies, preferably gravity-fed to avoid the need for pumping. The tankering of water is a very short-term solution which uses vehicles and fuel which could be more beneficially employed elsewhere.
Similarly, sanitation should be provided close to the displaced population, away from the source of water supply and on unsaturated permeable strata to allow sufficient drainage. These factors should be taken into account when locating refuges and other areas of residence.
Flooding may affect both roads leading to the flooded area as well as those within it. This can include blockages of debris and silt, as well as flooding or washing away.
The emergency plan should therefore identify the following:
- Access roads to and within the flood zone, avoiding low bridges over rivers, low- lying areas, roads susceptible to land slippage (in cases of flooding caused by heavy precipitation) and highlighting those not susceptible to crime and insecurity.
- The design and location of permanent signage on principal road routes.
The use of symbols avoids the difficulties of literacy and language.
- Suitability of road, railways and airfields, where available, for longer distance transport of supplies.
- Suitability of ports near main shipping lanes, with sufficient depth and with suitable loading and unloading facilities for international vessels.
Floods deposit large volumes of debris and mud, the clearance of which is essential for the relief effort. The emergency plan should identify how the debris and mud is to be cleared, by whom and where is to be deposited.
Emergency health facilities
Flooding may generate a range of injuries. The emergency plan should identify:
- The suitability of public buildings to act as preliminary treatment centers (such as schools, government offices or similar).
- Existing hospital facilities, away from the likely flood area, that may be developed with specialist services and equipment.
- The method of evacuation for those with more serious injuries.
- A system of vaccination.
- The suitability of public areas (such as parks and schools), for the siting of mobile clinics units, temporary camps and distribution centers.
- The provision of power, as electricity supplies (where these exist) are likely to have been severed.
It is likely that the floods will destroy access to energy resources, be they electricity or, in less developed areas, other forms of fuel including wood and animal dung. The emergency plan should identify:
- The local fuel resources and their continued accessibility during and after a flood.
- Alternative sources of energy (for example, generators) and the fuel to run them.
- Key institutions such as hospitals which should be supplied with these alternative sources and the methodology for ensuring their continued availability between floods.
Emergency situations, and the breakdown of the normal standards of society and their enforcement, often create opportunities for theft and corruption.
The emergency plan should therefore include:
- The securing of the facilities identified in the emergency plan, between and during flood events.
- The visible deployment of reliable security forces immediately post flood to deter looting.
- External auditing of government functions for efficiency and probity.
An appropriate and implementable emergency plan can:
- Facilitate emergency response.
- Minimize the impacts of flooding.
- Allocate resources efficiently.
- Reduce confusion.
- Facilitate recovery.