What part of a river would you have the best chance at growing food?

The best part of a river for growing food would be the floodplain. Floodplains are the areas of land adjacent to a river that are periodically flooded when the river overflows its banks. These areas are typically very fertile, as they are enriched by the sediment deposited by the floodwaters. Floodplains are also usually relatively flat and well-drained, making them ideal for agriculture.