Drawbridge Operation Regulation; Isthmus Slough at Coos Bay, 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 Oregon Department of Transportation's (ODOT) Isthmus Slough Bridge, mile 1.0 across Isthmus Slough at Coos Bay, OR. This deviation is necessary to accommodate painting and preservation and upgrading electrical systems. The deviation allows the bridge to operate in single leaf mode or one half of the bascule span, and reduce the vertical clearance of the non-functional leaf.

DATES:

This deviation is effective from 6 a.m. on September 1, 2017 to 6 a.m. on February 26, 2018.

ADDRESSES:

The docket for this deviation, USCG-2017-0715 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. Danny McReynolds, Bridge Management Specialist, Thirteenth Coast Guard District; telephone 206-220-7234, email d13-pf-d13bridges@uscg.mil.

SUPPLEMENTARY INFORMATION:

ODOT, bridge owner, has requested a temporary deviation from the operating schedule for the Isthmus Slough Bridge, mile 1.0 across Isthmus Slough at Coos Bay, OR. The requested deviation is to accommodate painting and preservation and upgrading electrical systems. To facilitate this event, the double bascule bridge will operate in single leaf mode (half of the span), and reduce the vertical clearance of the non-functioning leaf. Isthmus Slough Bridge provides a vertical clearance of 28 feet in the closed-to-navigation position referenced to the vertical clearance above mean high water tide level. Ten feet of containment will be installed under the closed-to-navigation leaf only, and will reduce the vertical clearance to 18 feet. Vessels that do not require an opening may transit under the bridge at any time.

The normal operating schedule for the subject bridge is 33 CFR 117.879. This deviation allows the Isthmus Bridge to operate in single leaf, half opening, and reduce the vertical clearance of the non-functioning leaf by 10 feet to 18 feet; and need not open for maritime traffic from 6 a.m. on September 1, 2017 to 6 a.m. on February 26, 2018. The functional bascule leaf shall open on signal if at least 24 hours notice is given. Waterway usage on Isthmus Slough includes vessels ranging from small commercial tugs, commercial fishing vessels, police search and rescue to small pleasure craft.

Vessels able to pass through the bridge in the closed-to-navigation position may do so at any time. The bridge will be able open half of the double bascule in single leaf mode for emergencies as soon as possible, and there is no immediate alternate route for vessels to pass. The Coast Guard will inform the users of the waterway, through our Local and Broadcast Notices to Mariners, of the change in operating schedule for the bridges so that vessels 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 their regular operating schedule immediately at the end of the effective period of this temporary deviation. This deviation from the operating regulations is authorized under 33 CFR 117.35.