The section of the Columbia River is called Wallula Lake, the reservoir impoundment created by McNary Dam.

British explorer David Thompson was the first European to navigate the entire length of the Columbia River, to the Pacific Ocean, in 1811.

The fort was abandoned in 1857 when the Hudson's Bay Company gave up its Columbia District business in the Oregon Territory.

Work done by Oregon and Washington State governments, federal and state environmental agencies and local watershed councils and groups on the Walla Walla River & the overall catchment area has produced a wide range of studies.

Considerable work has gone into the assessment of water quantity and quality for the purpose of salmon recovery and sustainable irrigation supply.

The promise of the Walla Walla River lies in its integrated water-management strategy using Managed Aquifer Recharge (Or Shallow Aquifer Recharge) to utilise available non-irrigation season water to replenish groundwater supplies and the over-allocation of groundwater resources by both state governments.