The Ann Arbor City Council voted unanimously Monday night to approve a $79,980 contract with Michigan Recreational Construction Inc. for improvements to Placid Way Park.

Under a separate resolution, the council approved a $27,776 change order to a contract with Site Development Inc. to address the failure of the stormwater system in West Park.

Placid Way Park, which includes a small neighborhood playground area on the city's northeast side, is located off Placid Way. The work being done there includes replacement of a play structure and picnic table, as well as the addition of benches and landscaping.

The play structure was installed in 1993 and does not meet current barrier-free codes, according to Amy Kuras, a landscape architect for the city.

The work being done at West Park is a continuation the city's efforts to address problems with the park's stormwater system installed a couple of years ago.

The City Council originally voted in November 2009 to approve a $1.59 million project to improve West Park. That included a $1.44 million contract with Site Development Inc. and a construction contingency budget in the amount of $144,300.

The work done at West Park included stormwater upgrades, access improvements, seat walls in the hillside at the historic bandshell, renovations to the bandshell, boardwalk and pond overlook construction, parking lot reconstruction, basketball court replacement, prairie, wetland and tree planting. The project also included installation of eight hydrodynamic separators that were designed to reduce sediment and phosphorus inputs into Allen Creek. In November 2010, one of the hydrodynamic units failed and controversy has continued to surround the project with neighbors complaining of flooding.

Five previous change orders have been approved within the 10 percent contingency amount to cover unforeseen changes, including undercutting due to poor soils, repairs from extensive storm damage, revisions to the stormwater structures in the park, additional work on Seventh Street due to conflicts with underground utilities, electrical service relocation, additional landscaping, and earthwork in conjunction with a house removed on Chapin.

City officials said a sixth change order in the amount of $27,776 was needed to make the site safe after the failure of one of the hydrodynamic separators, but that brings the contract amount above the 10 percent contingency originally approved by council in 2009.

"This sixth change order directed the contractor to provide barricade fencing around all eight units to prevent traffic and pedestrians from entering the area, backfill the hole created by the collapse, remove the weir wall from the diversion structure, and bulkhead of the pipes to prevent backwater from entering the structures downstream," reads a staff memo to council.

Ryan J. Stanton covers government and politics for AnnArbor.com. Reach him at ryanstanton@annarbor.com or 734-623-2529. You also can follow him on Twitter or subscribe to AnnArbor.com's email newsletters.