Water levels along the Columbia River, from Bonneville Dam to Longview, will decrease starting Labor Day weekend and could remain low for several weeks. This means Portland river levels could drop by up to two feet within 24 hours.
Boaters are advised to exercise extreme caution when anchoring near the shore as river levels could drop considerably in a matter of hours. The decrease will result from multiple effects of natural seasonal low flow, flow reductions from upstream dams and the influence of low tide.
