The effects of a downpour are worsened when terrain will not absorb water. Another cause of flooding in some areas is ice jams. In colder northern areas, ice sheets form on the surface of a river during cold winter months of low flow. Warmer weather and higher flows cause the ice to break up into huge slabs that the current pushes downstream. When these slabs pile up against some obstacle, they form a dam that causes water to pool upstream and flooding results.
Floods typically get the most headlines when waters are about to crest.
But there are important post-flood stories that need telling as well. Members of a flood-stricken community need all kinds of information to avoid pitfalls and deal with problems. For example, failure of normal sewage and drinking water systems means people need advice about how to find safe drinking water. They need to avoid pumping out flooded basements too quickly to prevent water pressure from destroying foundations. They need to understand and address the problems of mold and mildew in waterlogged buildings.