Dam future not as interesting as past

Autumnal colors bright the landscape along the old dam structure that spans Big Walnut Creek just beyond the Greencastle Water Works plant north of the fairgrounds property.

For a nice, round $100 fee, the Greencastle Water Works got a dam inspection and a history lesson.

And apparently the city won't really have to do much with either.

Back in July, the Indiana Department of Natural Resources sent inspectors to town to routinely examine the Big Walnut Creek dam behind the city water plant.

Classified as a low-hazard structure, it was built originally as a dam designed to pool the creek waters to facilitate a gristmill operation further up the Big Walnut to the north and east.

At one time, the structure in question paralleled the old covered bridge that spanned the creek from the 1880s until part of it was washed away in the infamous floods of 1957.

As a reminder of those bygone days, a large rock formation that was once part of the support for the old bridge still sticks up above the surface of the water just west of the dam.

The dam itself isn't worth a darn apparently.

"It serves us no real purpose," City Water and Wastewater Superintendent Richard Hedge said, "although it probably helps keep the water level up a little."

State inspectors have termed the five-foot-high, 10-foot-wide structure "conditionally poor," with cracked and missing concrete at both ends and a deteriorating crown.

The abutments fared better in the inspectors' assessment. They were described as appearing stable with no seepage found.

The whole story came up when the Board of Works was recently presented the $100 bill from IDNR for the dam inspection effort.

The presence of the 110-foot-long dam does pool the creek water behind it, which the report notes can impede canoers and kayakers and hinder fish migration. Fact is, few fish are able to jump the dam and continue south and west unless the creek is at or near flood stage. Despite a migration issue, the present situation can make for better fishing on the east and north sides of it.

Pooling of the water behind the dam also likely does help feed the city well field that provides water for about 60 percent of Putnam County. It's just that nobody apparently knows how much or how little effect that has on the well field water volume.

The city does not pump water directly from the creek, but gets it from the well field north and east of the fairgrounds.

It was also noted that the area behind the dam was reworked once before by packing it with stone and clay to retard a whirlpool effect that had had developed along the old structure. That had led to erosion and other issues.

"We really don't have to do anything," Hedge reiterated, adding the IDNR still hopes the city will remove the dam at some point. "They would like for us to take it out, but it's totally up to us."

With cost factors for such a removal project unknown and city officials uncertain what overall effect removal might have on the well field, board members didn't think it would be wise to consider taking the whole dam out.

Regardless, data about the dam and the creek will be collected and passed along to City Engineer Garth Hughes. He is expected to re-examine the situation in the spring.

Hedge suggested there is really no need rush into a decision. After all, the next INDR inspection won't be due for another five years or more.

The only action taken on the issue at the October meeting was the Board of Works' approval to pay the $100 bill.