West Lindsey District Council has confirmed that designers are drawing up plans for a swimming pool, and that the site is big enough to house one.
The district council is set to submit a planning application for the dry leisure centre, but plans are also being drawn up for a pool.
A WLDC spokesman said: “Any additional swimming facilities in the future will be dealt with as a seperate application.”
Market Rasen deputy mayor and town councillor Stephen Bunney said: “It is my understanding that the designs currently being drawn up will include the footprint of the swimming pool and associated features.
“When the pool section is given the go-ahead, plans will be submitted for the project based on the original designs submitted to the public.”
In response, a WLDC spokesman said: “Our design team have agreed to show residents where future expansion can take place on the site plan - but we have been clear that these will not be detailed proposals.
“This plan will be available at the community consultation session to demonstrate that future expansion is possible, and that the site masterplan and dry facility design has also taken account of future expansion.
“There is no point designing a facility until the business case is viable, as the costs involved in the design are substantial.
“At that point, plans will be drawn up and planning consent applied for.
Coun Bunney added: “We will be working hard to bring swimming facilities about, by working with residents and partner organisations to build the economic case for the project.
“The section on Leisure Facilities in the town council’s three year strategy is being altered to reflect the strength of public opinion for the swimming pool, as shown by the recent petitions and debate.
“The purpose of the strategy is to focus the work of the town council – therefore, we will be working with residents to deliver the full leisure project from day one.”