West Winds drainage issues identified, costs to be determined
The drainage problem at West Winds Development has nothing to do with development — old or new. It really has to do with how streets were constructed and the lay of the land.
The land is flat and there are no ditches along the streets to hold run-off from rain.
The solution is really quite simple.
Dig some ditches and replace the existing culverts with larger ones to handle the water.
Even though no cost estimate was known at the time, the hard part is going to be paying for it.
Bob Privatera of Reiss & Goodness Engineering told Hillsboro City Council at the June 3 council meeting that since Oak Street is lower than Pine Street, the elevation of the graveled street is causing one long dam.
Adding to the overflow is a 65-acre watershed west of the addition with all of that water eventually hitting the dam.
There is a watershed outlet on Oak Street that can handle five cubic feet of water per second. Privatera said the culvert needs to be expanded to carry 100 cubic feet of water per second.
A long-term solution is a water retention facility. Meanwhile, Privatera suggested a short-term solution of enlarging the culvert at Oak and D streets, adding a manhole, and then digging ditches along Oak Street.
That way rain and run-off water eventually will be directed to the ditches.
The water then would pass under D Street, across the drainage area on Marion County Fairgrounds, and end up on the Hillsboro Country Club property.
Another solution is to replace a section of curb and gutter with a valley gutter, and add a section of curb and gutter.
Privatera also suggested the possibility of re-developing parts of the subdivision that have not yet been developed. If the area was properly designed, the streets would become more functional and could drain naturally.
Mayor Delores Dalke asked the number and sizes of culverts needed. Privatera said two new culverts were needed and one could be removed. The next appropriate step of the engineering study would be to determine the culvert sizes, Privatera said.
Dalke pointed out to the council that the drainage proposal included running the water through a section of the fairgrounds that the previous council had considered discontinuing as a drainage route.
"It would be nice to have a culvert to the golf course," Dalke said.
City administrator Larry Paine said he would be concerned about the maintenance of a culvert of significant length.
Dalke also noted that there are lots for sale in the housing subdivision that could be developed before drainage issues are addressed. No solutions were determined to remedy the situation.
The council instructed Privatera to move forward with the pricing of culverts and ditch work with the work being considered in the 2009 or 2010 budget as a capital improvement project with costs shared with those residents who would benefit from the improvements.
Information will be shared with the city's planning commission in regards to having drainage issue addressed before plats are approved.