A detention pond in the archery field of Chingford Park in Northeast Valley, Dunedin, may be created to contain flood waters from Lindsay Creek to ease the risk for homes, schools and businesses in the area.
The Otago Regional Council has been investigating options for dealing with the creek's flood hazard after it dropped plans for extensive works as part of the Leith Lindsay flood protection works as the original plans were judged to be too expensive for ratepayers.
Instead, the council proposes an $840,000 project using a part of Chingford Park as a "detention" area, complemented by "small-scale localised works" between Palmers Quarry bridge and Pentland St and temporary flood detention upstream of Forrester Park landfill, a report to be considered tomorrow by the engineering and hazards committee said.
It recommended the committee consider approving the development of a works programme and funding options for consideration in the next annual plan.
Lindsay Creek is considered to provide a higher flood risk than is acceptable for an urban area, the report said. About 450 homes, schools, roads and commercial properties had some degree of exposure to flooding from the creek.
The intense subdivision of the area meant the space available for public works was restricted and increased the vulnerability of homes to flooding.
"Flood risk would be better managed if floodwater was directed to land where there is the least impact, avoiding flooding of land for which there are issues of public safety or significant property damage."
The council investigated Bethunes Gully, Forrester Park and Chingford Park, but Chingford had the best attributes and provided the option of two ponds being created, although only one was proposed to be built, the report said.
Grassed compact earth embankments of about 2m to 2.5m would be constructed, with a swale connected to the creek to direct the flow into the pond.
"The park would continue to be available for community use, with access restricted during times of expected or actual flooding."
Water would enter Chingford Park's ponding area whenever flows in Lindsay Creek were higher than about 20cumecs at that location - about the peak flow of the April 2006 flood.
There would continue to be flow on to North Rd during such floods but the volume and duration would be less, it said.
Resource consent would be needed for the work.
