Towering snowpack and frozen rivers are more than just a reminder of the bitter-cold winter; they are a flood waiting to happen.
Although the snow is gone in southern NH a quick trip up to Mt. Washington this weekend showed that the snowpack is still quite high in the White Mountains which will eventually feed into our rivers, streams and lakes thus the potential for more flooding in April and May. Remember the Mother’s Day Flood in May of 2006?
During the spring, frozen land prevents melting snow and rainfall from seeping into the ground. A quick spring thaw can produce large amounts of runoff in a short period of time. Each cubic foot of compacted snow contains gallons of water. With nowhere else to go, the melted snow runs off the surface and flows into lakes, streams and rivers, causing excess water to spill over their banks. Add rain storms to that mix, and the result can be serious, spring flooding. Many rivers also froze this winter. When a rise in the water level or a thaw breaks the ice into large chunks, these chunks can become jammed at man-made and natural obstructions, resulting in severe flooding.