flood control

these don’t really work, do they?

in the era of climate change where low-lying cities and riverside communities face an increase in floods, the humble sandbag is the current workhorse. there are large-scale solutions employed in cities like New York where landscaped berms along the waterfront allow water to wash in and out. for flood-prone areas, new construction codes lift critical building systems above forecasted tidal surges. in new orleans, where half the city is below sea level, survival is dependent upon engineered levees, canals, and drainage ditches. with each herculean effort by humans to defend against water’s intrusion, nature is the best defense. returning wetlands to coastal areas as the adaptive buffer forces new development further away from direct flooding. for existing communities along coasts and riverways, the insurance market is fleeing flood-prone areas while state-run insurance pools become the interim remedy. climate change requires increased funding for national emergency agencies like fema.

for the homeowner, many towns and cities allocate sandbags as the only solution. at about 30-50 pounds per sandbag, once filled, the homeowner is limited by how many they can transport. it takes 6-8 sandbags to block a single doorway. after a major flood, the sand and bag contain all the toxic contaminants carried in the flood waters. it’s then left to the homeowner to properly dispose of the sand and bags as most municipalities do not recycle or allow the sand to enter storm drains. instead, disposal is made at hazardous waste sites.

there are in-between solutions, larger than the sandbag and smaller than earth-moving, that exist. these are defined as removable and temporary barriers. they are typically deployed by municipalities and the army corps of engineers. the ease and speed of deployment of these systems is one measure of their success but they are not available everywhere. what defense systems do homeowners have if their communties do not have these resources on hand?

1. self-locking water dams that use the rising water to fill their cellular structure.

2. barrier dams are accordion-like cellular systems that can be filled with sand or gravel.

3. geo-barriers rely on water to anchor the system. the steel barriers are angled to allow the weight of water to increase the barrier’s stability.

1. water dam

2. barrier dam

3. geo-barriers

with the increase in flooding and the converse occurrences of drought worldwide, more communities will need robust services and equipment to restore ecosystems and adapt to climate change at the local level.