Those who use Lake Calhoun will finally have a chance to react to fairly specific proposals on parkland renovations there as part of a planning process that began last summer.

An open house to obtain comment on proposals by planners for modifying the Calhoun shoreline will be held from 6:30 to 8:30 p.m. Thursday at St. Mary’s Lake Calhoun Event Center, 3450 Irving Av. S.

Park planners will display concept alternatives for the parkland surrounding the lake that fall under two models — one with greater emphasis on recreation and another focused more on improving the lake’s environmental health. However, there is considerable overlap between them.

The focus of discussion will be ideas for revamping the lake over the next 25 years, beginning with $3 million now allocated by the Metropolitan Council. That work, at both Calhoun and Lake Harriet, is expected to start in 2017. The ideas presented by planners for the northeast, north, northwest and southwest shores of the lake probably would require many more millions of dollars and a long period to implement.

The most ambitious idea is constructing a grassy land bridge over W. Lake Street to better connect Calhoun with Lake of the Isles. Another key proposal would disperse some of the multiple activities at the lake’s refectory area in the northeast corner by shifting boat launches to a north parking lot and the sailing school to the northwest corner.

The committee advising park planners on a long-term master plan is scheduled to meet on Nov. 17 to review design concepts for the eastern and southern shores of Lake Calhoun and for nearby lake areas. Those awaiting discussion include William Berry Parkway, the Harriet band shell area, the east shore of Harriet and Lyndale Park.

The key concepts outlined but not yet discussed for those areas are a land bridge for the intersection that connects south Calhoun with Berry, closing the lower section of E. Lake Harriet Parkway and extending gardens at Lyndale Park to the lakeshore. A public open house on those proposals is expected in early January.