The dam project, which is due to include the draining of Albin Pond, will be funded by a $530,321 grant received by the City of Greencastle from the Office of Community and Rural Affairs (OCRA).
The Board of Works has authorized Mayor Sue Murray to sign a contract with the firm JDH Contracting, Plainfield, and subsequently to issue a notice to proceed.
JDH offered the lower of two bids submitted on the project at $497,413.50 -- some $850,000 less than $1,349,027 from Yardberry Landscape Excavating Co., Anderson, at a recent bid opening. The Yardberry bid was opened first to audible gasps.
"That's called getting the sticker shock out of the way early," Board of Works member Trudy Selvia said in making the motion to accept the JDH bid, which also met with Mayor Murray's approval.
Board member Thom Morris abstained since he lives within the affected area.
Construction is expected to commence July 1 and be completed by Oct. 1.
The Albin Pond dam rehabilitation effort is an Indiana Department of Environmental Management (IDEM) mandated project. The dam has been classified by the Indiana Department of Natural Resources (IDNR) as a "high hazard dam" due to its age and condition and the proximity of two homes downstream of the embankment.
An uncontrolled breach of the dam could predictably result in damage to property, buildings, roads and utilities as well as potential injury or loss of life, a study indicates. Damage to the existing railroad could also result from such dam failure.
In 2010, an Emergency Spillway Capacity and Hazard Classification Study on the dam was conducted and verified the current "high hazard" classification. It noted that runoff from a Probable Maximum Precipitation (PMP) rainfall event could cause a breach of the dam, and those results could be devastating to infrastructure and homes within the area. Currently, the dam is considered capable of detaining only about 40 percent of that runoff amount.
The proposed Albin Pond dam rehabilitation project includes:
-- Removal of the existing spillway to be replaced with a reinforced concrete drop inlet spillway and reinforced concrete outlet conduit.
-- Flattening of the dam slopes to improve stability and maintainability.
-- Widening of the 20-foot-wide roadway to meet current minimum city standards.
-- Addition of a grass safety berm for pedestrian access and future extension of the existing pedestrian pathway to the west.
Albin Pond Road, which crosses over the dam, is classified as an Urban Collector Street, heavily traveled by both vehicles and pedestrians. The existing roadway has reportedly been experiencing longitudinal cracking as well as shoulder failure because of the steepness of the dam's slopes.
One of the big concerns regarding the dam is the major water line that runs along the crest of it. The water line serves the East Side industrial area, including manufacturers such as Crown Equipment, Chiyoda USA, IAC and the Dixie Chopper Business Center at the airport. The water line is considered vital in maintaining water pressure and fire protection.
The line also provides water to the Town of Fillmore. If the dam were to breach and cause the water line to burst, the industrial area and the Town of Fillmore could be without water until necessary repairs can be made.
The first known inspection of the dam was in 2000, and revealed the dam to be in deteriorating condition.
In 2004, the city conducted another inspection, and the dam was again judged in "conditionally poor" shape based on IDNR rating criteria.
Inspection reports consistently have noted the need for additional maintenance, engineering studies and construction to improve the inadequate spillway system, the deteriorated condition of the stone drop inlet riser, inlet obstructions, the steep downstream slope and trees growing on the embankment.
From 2004-06, the city undertook several inspections, engineering surveys and improvements to the dam, including guardrail and sign installation in the amount of $6,600 and weed, tree and brush removal, chain link fence installation and stump removal totaling $19,000.
For the city's commitment to the project, a total of $15,650 of local match will be utilized. The city has previously invested $3,500 on a topographic survey, $6,500 on an emergency spillway capacity and hazard classification study, $2,500 on right-of-way surveying and $3,150 on preliminary engineering.
The Albin Pond dam embankment was originally constructed in the 19th century as a railbed. As the railroad was built, a stone arch was laid to convey water and cattle across the right of way.
When the railroad closed early in the 20th century, the bed came to be used as a county road. During the 1930s and 1940s, the Works Progress Administration (WPA) built a hand-laid stone arch drop inlet spillway to impound what is now Albin Pond.
The existing earthen dam and accessory structures consist of an approximately 21-foot-high and 400-foot-long earth-filled dam with an eight-foot diameter corrugated metal pipe principal spillway conduit extending through the embankment.