North Dakota's state engineer is not required to limit irrigation water withdrawals from an aquifer system to maintain the level of a Kidder County lake, Attorney General Wayne Stenehjem said.

Lake Isabel, which is southeast of Steele, has been dropping for years because of a lack of rain and irrigators' use of aquifers that feed it. The aquifers are used to irrigate almost 11,000 acres, which are used mostly for growing potatoes and other vegetables.

The lake has more than 250 homes along the shoreline, and is used for swimming, fishing and boating. It has an average depth of about 6 feet. Its level has fluctuated greatly over the years, and it was dry during the 1930s, state Water Commission records say.

Three Republican state legislators - Mandan Rep. Todd Porter, Bismarck Rep. Mark Dosch, and Bismarck Sen. Ed Kringstad - asked Stenehjem for a legal opinion about whether lakeside landowners and the Game and Fish Department have a right to lake water, similar to water use rights held by irrigators.

Stenehjem's opinion, issued Wednesday, said recreational lake use is not considered an appropriation of water. The Water Commission's chief engineer is not required to limit aquifer water use by its 51 permit holders to maintain the lake level, the attorney general said.

The Water Commission has not issued new permits for aquifer use for seven years because of falling water levels.

To establish a right to water use, the aspiring rights holder must have a way to use the water, Stenehjem's opinion says.

"Water appropriations require the construction of works, by which water is diverted and put to a beneficial use," the opinion says. "There are no such works (on Lake Isabel). Thus, it is my opinion that at Lake Isabel, no water rights exist for fish, wildlife and other recreational uses."

The state engineer has a duty to manage the lake and the aquifer system's water use, but is not required to reallocate water used by private permit holders to public uses, Stenehjem said.