Background Thousands of acres of arable land is often flooded and inundated in the Red River Valley in North Dakota and Minnesota,resulting in loss of productivity and income. Much of the valley has low gradients, with slow drainage and even a small amount of above normal or intense precipitation leads to inundation. In order to make insurance claims and to improve drainage, an accurate delineation of the damaged areas is necessary. The farmers of St. Thomas, ND, who were faced with the problem flooding and inundation, were able to derive information from IKONOS imagery for insurance claims and to convince the local water board to improve drainage.

 Use of Data Ikonos images were acquired for 07/09/2001, 08/05/2001 and 08/27/2001. The first image showed no inundation, while the second, subsequent to heavy rainfall, showed several wet spots or "drown out" areas, affecting the crops. The third image showed continued inundation, though some fields started drying up by then. Section 24 of North St. Thomas was particularly devastated by the water damage. The imagery showed that a 75.4-acre field with red potatoes was severely affected. While the average yield in the rest of the potato fields was 150 hundredweight per acre, this field produced only 89 hundredweight per acre. After an adjustment for crop insurance, this yield reduction is estimated to have resulted in an income loss of over $350.00 per acre or over $26,000.00 for the whole field.

 Economic and Environmental Benefits The imagery was useful in assessing the acreage lost due to water damage and in supporting claims for insurance. More importantly, the imagery showed that the drain system around the section needed maintenance and helped to bring this to the attention of the water board. This not only avoids water logging and associated environmental problems, but also ensures future productivity of the land.