routes

PHOTO 5.8

Use of turfing combined with jute netting

Source: © The Vetiver Network. Used with permission. Further permission required for reuse.

TABLE 5.4 Recommended practices for roads as flood shelters and evacuation routes

RECOMMENDED PRACTICE

Road alignment Prioritize the development and heightening of roads leading to designated emergency shelters.

Polders Create heightened road bodies in low-lying areas of the polder to create safe routes and safe temporary shelters during flood events and refuge areas in the post-flood scenario.

Embankment and flood protection Create levees along vulnerable sections of the roads to protect roads and embankments and create flood and post-flood shelters for humans and livestock.

Evacuation Plan evacuation routes using road infrastructure.

Source: MetaMeta (www.roadsforwater.com).

Consider levees along roads to temporarily accommodate flood-affected persons

In addition to raising the roads in the lowest sections of low-lying coastal areas, levees may be created along internal roads and along specific embankment sections. These levees can shelter people and livestock during floods and highwater events. These higher sections should be created in especially high-risk areas using the remaining silt from the excavation of canals, ponds, or rivers. Such sections along the roads could provide the opportunity to temporarily accommodate flood victims (people, cattle, and goods) until their homes have been rehabilitated (photo 5.10). Levees should be spaced at strategic distances so that they are accessible throughout flood-prone areas, placing them along more exposed sections of flood embankments so they can serve as additional reinforcements. The same may also be done for the area outside the embankments. finally, use of these levees should be regulated by local governments to prevent the undesired permanent occupation of flood shelters.

Plans for emergency facilities should be based on estimates of the number of people and livestock that will depend on them during floods. as a rule of thumb, the minimum space needed for a person to take shelter lying down is 1.5 square meters. although that is sufficient space over the short term, 3.5 square meters of covered area is more appropriate for longer-term emergency space (Red Cross 2013). an average household in Bangladesh, for instance, has 4.6 members

PHOTO 5.9

Cyclone shelter, Bangladesh

Source: © MetaMeta (www.roadsforwater.com). Used with the permission of MetaMeta (www.roadsforwater.com). Further permission required for reuse.

PHOTO 5.10

Embankment used as a temporary flood shelter

Source: © MetaMeta (www.roadsforwater.com). Used with the permission of MetaMeta (www.roadsforwater.com). Further permission required for reuse.

(Begum 2004). a family can therefore be assumed to need a shelter area of approximately 15–16 squaremeters. for livestock, a space of 2–4 meters per head would suffice. Therefore, 85 people can take shelter (without livestock) on a longitudinal section of a 100-meter embankment with a width of 3 meters. If there are multiple areas of 300 square meters in specific locations along an embankment, the number of people who would benefit from temporary shelter is proportionally higher.

Such levees should be protected by stabilizing their embankments with hedges, vetiver, and other grasses on their slopes and toes to protect them from erosion (Islam 2000).

Plan and mark evacuation routes

despite emergency preparedness programs and early-warning systems, pre-emergency evacuation remains a challenge in coastal villages in developing countries. In rural areas there remains a lack of awareness and communication to enable people to understand the warnings and evacuate. Moreover, dissemination of warning messages is inefficient because poor residents in coastal areas may not have access to means of communication (Haque et al. 2012). during floods and typhoons, roads are an important part of the evacuation of people and livestock. Part of emergency preparedness should be to plan evacuation routes, which can be done by

• Mapping population centers; • Mapping road networks and looking at the above-ground level of roads; • Mapping for floods, inundation risk, and escape routes (figure 5.3) (WMo and GWP 2011); • Putting in place flood signs (boards, poles) along the roads as part of evacuation-route planning, especially in areas that are easily inundated; the aim is for escape routes to remain visible during emergencies (Photo 5.11) (WMo and GWP 2011); and • Raising awareness so that a large share of the population is familiar with evacuation routes.

Managed retreat, relocation, realignment

In some areas with extraordinarily high risks of erosion and flooding, especially in coastal lowlands, managed retreat, relocation, and realignment (purposeful, coordinated movement of people, buildings, and infrastructure away from risks) can be considered as a cost-effective and feasible solution to address present and future risks. although this approach has not been broadly implemented because of the difficulty of building consensus, there are some examples in the recovery and reconstruction of communities after devastating disasters (such as the “Build Back Better” program after the Great east Japan earthquake and Tsunami of 2011).