Drawbridge Operation Regulation; Willamette River, Portland, OR

AGENCY:

Coast Guard, DHS.

ACTION:

Notice of deviation from drawbridge regulation.

SUMMARY:

The Coast Guard has issued a temporary deviation from the operating schedule that governs the Morrison Bridge across the Willamette River, mile 12.8, at Portland, Oregon. The deviation is necessary to accommodate Multnomah County's replacement of the bridge decking. This deviation allows the bridge to only open half of the span, single leaf, to allow for the replacement of bridge decking. The deviation also allows the vertical clearance to be reduced due to the project's containment system.

DATES:

This deviation is effective from 6 a.m. on April 1, 2017 until 7 p.m. on September 27, 2017.

ADDRESSES:

The docket for this deviation, [USCG-2016-0474] is available at http://www.regulations.gov. Type the docket number in the “SEARCH” box and click “SEARCH.” Click on Open Docket Folder on the line associated with this deviation.

FOR FURTHER INFORMATION CONTACT:

If you have questions on this temporary deviation, call or email Mr. Steven Fischer, Bridge Administrator, Thirteenth Coast Guard District; telephone 206-220-7282, email d13-pf-d13bridges@uscg.mil.

SUPPLEMENTARY INFORMATION:

Multnomah County has requested that the Morrison Bridge across the Willamette River, mile 12.8, be allowed to only open half the span, 92 feet, as opposed to a full opening, 185 feet, to accommodate the replacement of the bridge decking. The County has also requested to reduce the vertical clearance of the non-opening side of the span with scaffolding erected 10 feet below the lower bridge cord for a containment system and to require at least a two hour advance notice for an opening. The Morrison Bridge is a double bascule bridge. When the bascule span is in the closed-to-navigation position, the bridge provides 69 feet of vertical clearance, which will be reduced to 59 feet with the containment system in place. The normal operating schedule for the Morrison Bridge is in accordance with 33 CFR 117.897(c)(3)(iv). The vertical clearance is above Columbia River Datum 0.0.

The deviation period is from 6 a.m. on April 1, 2017 until 7 p.m. on September 27, 2017. The deviation allows the Morrison Bridge operator to only open half the span for maritime traffic with at least a two hour advanced notice. Waterway usage on this part of the Willamette River includes vessels ranging from commercial tug and barge to small pleasure craft.

Vessels able to pass through the Morrison Bridge in the closed position may do so at any time. A tug will be on site to assist vessels through the single leaf span opening upon request. The bridge will be able to open half the span for emergencies with a two hour notice and there is no immediate alternate route for vessels to pass. The Coast Guard will also inform the users of the waterways through our Local and Broadcast Notices to Mariners of the change in operating schedule for the bridges so that vessel operators can arrange their transits to minimize any impact caused by the temporary deviation.

In accordance with 33 CFR 117.35(e), the drawbridge must return to its regular operating schedule immediately at the end of the designated time period. This deviation from the operating regulations is authorized under 33 CFR 117.35.