By Great movements of water like this can also cause displacement of animals. Many of the environmental effects will have to be calculated after the human disaster is dealt with, but among those attracting attention now are the owners of an alligator farm who warned on Monday that hundreds of the reptiles would be set free if the water rose by just another foot.
And fire ants, ejected from their underground homes, made floating islands to keep their queens alive until the water receded.
There may be other negative effects that become clear in the future – near New Orleans, Hurricane Katrina damaged swamps that play a vital part in absorbing floodwater, so making future flooding more likely.
People’s health
Multiple hospitals and nursing homes have been evacuated due to the floods, and hospitals have had to rely on backup systems for electricity and internet access.
In a disaster situation like this, routine appointments are often disrupted too. The Washington Post interviewed John McMillian, who was in town for five days of leukaemia treatment but was cut off from the hospital and could not make it to the fourth day.
People have been warned to make sure their tetanus vaccinations are up to date before they start clearing up in their homes, because of the risk of stepping on something sharp. And as some stagnant water is left behind it may become a breeding ground for mosquitoes, which in Texas can carry West Nile virus, a potentially-fatal fever.
The economy
Houston is at the centre of many industries, chief among them energy. The area is home to almost half of US refining capacity and a fifth of its oil production, meaning it makes a 2.9% contribution to US GDP. But property damage has stopped half the area’s oil refineries from working, and the low supply pushed the US financial market price of petrol up 4% to a two-year high.
One estimate suggests two million barrels a day of refining capacity has been lost – equivalent to about 10% of US national demand for products such as petrol, aviation fuel and heating oil.
Morningstar Commodities Research said on Tuesday that 11 more refineries, with a combined capacity of 1.3 million barrels per day, were at risk of closure.
The economic damage was not confined to the energy industry, however. Outside the city, the deluge wiped out a promising crop of cotton, and there are reports of farmers working 24 hours a day as the storm approached but still not managing to bring the whole harvest to safety.
Water will recede and properties will dry again after the flood, but it will take months or years to clean homes and businesses and make them fit for purpose again. It is estimated the insurance bill will hit more than $10bn.
this post originally appeared on the BBC
