Gin Creek, a small but popular brook trout stream in Ashland, WI, is now flowing clear again, at least for fish passage. 

The Ashland NFWCO has completed a culvert replacement on the Silver Brook Road crossing, opening approximately 3.7 miles to spawning/rearing habitat above the road crossing.  Two small, perched culverts were blocking upstream migration, and flow velocities in the culvert were also a problem for smaller fish. 

Gin Creek is a tributary to Trout Brook, and joins just below the culvert that was replaced earlier in the year on Trout Brook by Ashland NFWCO.

Funds from the Region Fish Passage Program were used to purchase a new 6' x 60' culvert and the Town of Ashland supplied manpower and equipment along with funds to contract with the Ashland County Highway Department to do the excavation at the site.  Ashland County Land Conservation Department, along with Ashland NFWCO conducted the pre-construction survey for the engineering plans and the ACLCD did the engineering plans for the site. 

Construction started on August 8 and was finished on August 9, 2007.  The plans called for a 1 percent slope at this site, with the culvert being set with 25 percent of the culvert embedded. 

Unfortunately this site had other plans, as the crew soon ran into bed rock below the old culvert.  With the excavator working on breaking up a channel in the bedrock we were able to set the culvert at a 1.5 percent slope, and embedded at around 18 percent.  It was decided to also set up a small series of step pools on the downstream side of the culvert and it increased the volume of water so that close to 25 percent of the culvert was filled with substrate and water.    

Even with the drought conditions experienced by northern Wisconsin in 2007, Gin Creek is mainly spring fed so a decent flow was still going through the culvert. 

Ashland NFWCO conducted pre- and post- construction fish surveys. The pre-construction survey was conducted on August 7. A total of 14 brook trout and numerous creek chubs were found in the survey.  The brook trout ranged in size from 55mm to 190 mm.  Brook trout found below the culvert were given a lower caudal clip and the upper stretch were given an upper caudal clip. 

The post construction survey was conducted on September 5.  It appeared that the fish really hadn't moved much, as there were no significant rain events before this survey, and 12 of the original 14 brook trout were recaptured, basically in the same spots they were found in the first survey. 

A follow up survey is planned in the spring of 2008 to see if any of the different clips can be found in this stretch.