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CINCINNATI Enterdepartrnent Correspondence Sheet
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Date: January 9, 2012 FOR YOUR INFORMATION TO: FROM: SUBJECT:
Mayor and Members of City Council 4~Jv’1ilton Dohoney, Jr., City Manager0~j4~ Update on Columbia Parkway Landslides
On Saturday, January 7, 2011, City crews and contractors removed a large landslide on Columbia Parkway west of its intersection with William H. Taft Road. Crews successfully completed this removal well in advance of their anticipated schedule, and the traffic restrictions were removed from the Parkway later on Saturday. However, a new landslide developed overnight immediately east of this slide. Traffic restrictions were re-established on Sunday afternoon for the safety of the traveling public, and notice was provided to the area media outlets so the public could find alternate routes for this morning’s commute. Public Services crews remained in place overnight to monitor the landslide in the event the slide would move more quickly than anticipated. Columbia Parkway is currently restricted to one lane in both directions. Crews are currently removing the loose material from the hillside; this work will last through this evening’s rush hour, but work will be complete and the road re-opened for tomorrow morning’s commute. Crews will continue into the evening until the work is complete. Discussions about long-term solutions to remedy landslides along Columbia Parkway, and elsewhere around the City, must be made within the context of the wettest year in recorded history and the unstable geology of the region. There were an enormous number of landslides in 2011, so many so that the City qualified for FEMA disaster assistance. There are many years, with less than average precipitation, when there only one or two landslides significant enough to affect the public rights of way. For example, in 2009 there were 3 reports to the City’s Customer Service system of landslides along Columbia Parkway; in 2010 there was 1 report. By comparison, there were over 18 reports in 2011 and 10 reports in 2008, another wet year. DOTE’s approach to landslides is to monitor known areas of landslide activity and implement mitigation measures where the greatest benefit can be achieved. In many areas, including Columbia Parkway, previously active landslides may move, but then remain stable for several years unless acted upon by other activities like the removal of trees and vegetation, or as in this year, excessive rainfall. The periodic removal of landslides from the Parkway, while frustrating, permits stable material to remain in place as long as possible and maintains the integrity of the landscape along the hillside. A new wall upslope of the existing wall, in addition to being extremely expensive, requires the removal of a large swath of trees and vegetation along the hillside, creating considerable disruption to the landscape and some potential to introduce new instability to the hill, and thus, new landslides. Additionally, any wall construction will introduce lengthy traffic delays as access uphill is extremely limited, and construction and staging activities will have to take place from the Parkway. Complicating the issue further is the origination of the landslides. Much of this area along the Parkway is held in private ownership. Although these current landslides began on private property, the City determined it to be in the best interest and safety of the public to expend public resources to clean up these landslides before they caused traffic hazards. cc: Michael R. Moore, Director, Transportation and Engineering~~~~