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Flooding The regional drainage of the Glacial Lake Agassiz's water some 9,000 years ago created what is now known as the Red River Valley. This valley is one of the youngest geological features of the lower 48 states, dating thousands instead of tens of million years old, and is one of the flattest regions on earth. As a result, the river is still forming its river valley; a valley that has yet to carve out a significant flood plain to hold in high waters. The lack of a significant valley makes the actual floodplain for the Red River the flat expanse of the Lake Agassiz's lake plain, allowing flood waters to cover considerable areas (Figure 1.7) (Schwert 2003). Compounding the topographic features causing flooding is spring thawing, ice jams, and a lack of gradient as the river moves downstream. The Red Rivers northerly flow and the spring thaw in the region progressing northward along the valley results in the southern valleys snow melt merging with fresh runoff as it moves north increasing the total amount of water in the river. Furthermore, the rivers inconsistent thaw can cause ice jams as large broken pieces of ice moves north reaching impassable frozen sections of the river creating ice dams retaining the water upstream. Finally, as the river moves north its gradient also decreases, this decreasing gradient causing the river to pool upstream (Schwert 2003). While the geological formations of the Red River Valley and its potential for flooding can not be changed and flooding on already established neighborhoods and developments can only be lessened with substantial financial investments, if it all, it is still possible to lessen the damage of floods for new developments by taking a proactive approach, "Often the most efficient approach to resolving a geological problem is to avoid the problem in the fist place" (Schwert 2003, 14). Using a proactive planning approach will not fix past mistakes, but can help to eliminate or lessen burdens created by flooding for future development. Allowing development in flood prone areas by infilling or diking not only puts these structures at risk for flooding, but also reduces natural storage area and creates bottlenecks in the flow ofthe river. Restricting growth in these 11