The Columbia River exceeded flood stage at the Interstate Bridge on Tuesday.
The river reached 16 1/2 feet at the bridge, where the flood stage is 16 feet.
The Oregon Department of Transportation reports the level is expected to reach at least 17 feet, depending on the rain, in the next few days.
FOX 12 meteorologists expect mainly wet weather over the next week.
High river levels have already meant more recent bridge lifts, which now average nearly two per day. Lifts usually last 15 to 20 minutes.
The river is now running very fast at the Interstate Bridge, according to ODOT, causing more ships to choose to pass under the bridge at the lift span at the north side of the river instead of the mid-river high span.
By taking the lift span, vessels avoid speeding through the high span and making the quick swerve necessary to reach the swing span on the north side of the BNSF Railway Bridge, a half mile downstream.
Under maritime law, bridge lifts have priority over highway traffic. However, no lifts are allowed during the morning and evening commutes, from 6:30 a.m. to 9 a.m. and again from 2:30 p.m. to 6 p.m. most weekdays.
In 2015, average daily traffic on I-5 over the Interstate Bridge was 132,300, according to ODOT.
The last time the Columbia River was this high at the Interstate Bridge was May 2011, when it reached 19 feet from rain and an early snowmelt.
The river reached 24 feet in 1996, part of major flooding in the Portland area.
The Army Corps of Engineers is also warning boats along the Columbia River to watch out for underwater hazards due the current high water levels.
Some pilings are barely sticking out above the surface of the river, and experts told FOX 12 that in some places, pilings that would normally be four feet above water are now completely submerged.
If a boater were to hit them that would mean catastrophic damage to the hull or engine. To make matters worse, anyone on a disabled boat in those circumstances would be swept away pretty quickly with the river’s currently moving so fast.
Safety officials remind anyone going on the water that conditions may not be what they are used to navigating.
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