In a 6-1 ruling on Tuesday, the Montana Supreme Court upheld a district court ruling that limted the number of household wells that subdivision developers could drill without a water-permit exemption. The ruling preserves Montana’s system of water rights that gives priority of water use to owners of older water rights and could ultimately keep more water in Montana’s streams.

Writing for the majority, Justice Laurie McKinnon went into 24 pages of detail as to why a district court judge was not mistaken when he voided a rewritten 1993 Department of Natural Resources and Conservation rule that allowed developers to sink unlimited numbers of household wells without needing a water permit. In addition, the court ruled that the previous 1987 DNRC rule limiting exempt wells would stand for now.