Closure structures are components that are placed or erected at various openings in the floodwall and levee during a flood event. Openings were built into levees and floodwall where it was not practicable to ramp railroads or highways over the flood protection system. These openings must be closed during periods of high waters. Aluminum panel closures are utilized at larger openings while smaller/shorter openings, particularly those requiring less frequent closures, are closed by sandbagging.
There are 6 closure structures of 2 different designs
at various locations throughout the system.
Number and specific type are:
2 - Sandbag
4 - Aluminum panel (2-vertical and 2-horizontal)
Closure structure installation is an extremely laborious task, sometimes requiring approximately 50 persons and an extreme amount of “man-hour” time. During the Flood of 2011, it took 225 hours to install closure structures to seal the city from the rising waters of the Susquehanna River and Shamokin Creek. Closure No. 7, a sandbag closure took approximately 60 volunteers 1 and 1/2 hours to install.
Following the Flood of 2011, the Authority secured state grant money to modify existing Closure #7. Modifications include the rebuilding of the bituminous sill to current rail level thus eliminating over 1 foot of filled sandbags required to seal the closure and the building of an access road to the closure to bring sand closer to the sill. These modifications will result in a significant reduction in both manpower requirements and installation times.
Each year, in the fall, the Authority coordinates a simultaneous closure structure training exercise at various locations throughout the city.
The exercise is scheduled as a competitive event where City of Sunbury and Municipal Authority crews and volunteer crews from the Sunbury Fire Department compete against each other to beat previous installation times. The event rotates City/Authority and volunteer crews in an effort to reduce response time during an actual flood event.
Following each exercise, crews meet to discuss ways to improve on their time for the next training event. To date, training records indicate that each year the rotated crews have been successful at beating the prior year’s installation record. In many cases, installation times have been reduced to just minutes.