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Indianford Dam background

Lake Koshkonong is over 10,460 acres in surface area and is located in Jefferson, Dane and Rock counties. The Indianford Dam impounds Lake Koshkonong. The dam is located more than 5 miles downstream of the lake in Rock County.

Water level comparison table

This table summarizes the current operations of the Indianford Dam and compares it to the Rock-Koshkonong Lake District (RKLD) requested lake levels.

Lake Level
(at lake, USGS gauge)
1991/2004 Existing Lake Levels* RKLD Requested Lake Levels* Change
May through October
Target 776.20' 776.80' +0.60' (7.2 inches)
Maximum (all slide and wicket gates open) 776.33' 777.00' +0.67' (8 inches)
All gates can close 776.10' 776.40' +0.67' (8 inches)
November through April
Maximum (all slide and wicket gates open) 775.77' 777.00' +1.23' (14.8 inches)
Minimum 775.00' 776.40' +1.40' (16.8 inches)

* Levels are in NGVD 29 datum; add 770.00 to the USGS gauge reading

Water level order history

Year Summary of events
1991 The DNR issued an order (3-SD-82-809) establishing water levels on Lake Koshkonong and operating procedures for the Indianford Dam. The order required operation of the dam based on level at the lake as opposed to at the dam. The order was issued after considerable legal review and negotiation. (For more information, see 1991 Water Level Order Finding of Fact and the 2005 Environmental Assessment.)
2003 The RKLD requests that the DNR change the water level order to increase the Lake Koshkonong water levels held by the Indianford Dam during the summer and winter. (See the Water Level Comparison table for existing and proposed water levels.)
2004 At the request of Rock County and the RKLD, the DNR reissued water level order (3-SD-82-809 Amended) to change dam ownership from Rock County to the RKLD, use the new USGS Rock River gauge at Fort Atkinson instead of the Rock River gauge at Watertown and the Crawfish River gauge at Milford. Lake water levels were not changed.
2005 The DNR issued a revised water level order (2-SC-2003-28-3100LR) which denied the increased water levels in the summer and raised the water levels in the winter but not as high as the RKLD had requested. The RKLD, the Rock River - Koshkonong Association, Inc. (RRKA) and the Lake Koshkonong Recreational Association, Inc. (LKRA) requested a contested case hearing to appeal the DNR's order.
2006 A 10-day contested case hearing was held in March and April. The DNR, RKLD, RRKA, LKRA, Lake Koshkonong Wetland Association and Thiebeau Hunt Club were represented. Additionally, 46 members of the public provided sworn testimony. In December, the administrative law judge found in the DNR's favor and the 2005 order remained in place. In December, the RKLD, RRKA and LKRA filed in Rock County Circuit Court for judicial review.
2008 In May, the Rock County Circuit Court judge affirmed the administrative law judge's decision. In June, the RKLD, RRKA and LKRA filed an appeal to the Court of Appeals, District IV.
2011 The Court of Appeals came in July and again affirmed the earlier rulings.
2012 The Wisconsin Supreme Court agreed to review the Court of Appeals decision.
2013 The Wisconsin Supreme Court rendered their decision reversing the Court of Appeals and remanded the case to the Rock County Circuit Court. The Supreme Court ruled that the DNR should have taken into account the economic impact of lake levels on lake front homeowners and adjacent businesses. A copy of the Supreme Court's decision can be found in the Resource section on the webpage.
2014 In February, Rock County Circuit Court remanded the case back to the DNR to again review the RKLD water level request following the Supreme Court's Guidance.