Records of the Association’s activities from 1939-1957 are scarce. The Association did take action to settle the issue of the water level of the lake. Under the supervision of Wisconsin State Conservation Department, a dam was constructed at Mirror Waters to control the flow of water. The Association worked to achieve its objectives through such activities as spraying the lake to control algae, swimmer’s itch, and weed growth (William Knapp, President of DLIA, Letter to members and property owners, October 29, 1970). The Association became inactive in 1959. The issue dividing the membership may have been funding for July 4th fireworks, a dispute between using voluntary contributions or money from the dues.
In 1969, several lake residents became concerned about the water quality of the lake and DLIA was revived. The Association was legally incorporated, without stock and not-for-profit (Articles of Incorporation, July 22, 1971), and its Constitution and bylaws were revised. Its object was stated in slightly different language “…for the…purpose of promoting, assisting and encouraging the purity and wholesomeness of the waters of Deer Lake, Wisconsin and the development and maintenance of the real estate adjacent to said lake and preservation and improvement of the aesthetic beauty there of” (Bylaws of the Deer Lake Improvement Association, Inc.). All property owners on Deer Lake were eligible for membership; but to become a member, a candidate had to apply to the Board of Directors and that application constituted the candidate’s support of the purposes and regulations of the Association. When the directors approved the application, the candidate, upon payment of the year’s dues, became a member.