TOWN centre footfall for the three months to June was down 13.5 per cent on last year, new figures show.
Council bosses say there are a number of short-term measures aimed at curbing the downturn in visitors, pending long-term change through the masterplan.
Some 200 extra parking spaces were made available from Monday at the former Tesco site on Forge Island.
Charges apply in the new area during the week but the spaces will be free at weekends, Rotherham Borough Council announced.
Cllr Denise Lelliott, Cabinet member for the local economy, said: “It is a timely boost to town centre businesses in the forthcoming autumn season and in the run up to the busy Christmas retail period.
“We encourage visitors to come into the town centre and explore the wide range of town centre independent shops and use the extra car parking spaces.”
Longer term hopes for the town centre hinge on delivering the aims of the masterplan, which was published in June.
A leisure development on Forge Island - including a cinema, hotel, bars and restaurants - is the key target.
The council wants to find a partner to form a joint venture development for the site and hopes to see building work start in the second half of 2018.
The masterplan will be formally adopted by Cabinet at a meeting on Monday.
A report to members said: “Delivery of the town centre masterplan is dependent on private sector investment.
“Although the soft marketing carried out to date has stimulated a very encouraging level of interest from developers and investors, it may be necessary for the council to pump-prime development using its land holdings and some public sector funding as seedcorn money to ensure the projects come forward.”
The masterplan also includes a revamp of the markets, street facelifts and riverside housing - as well as the previously announced university campus and replacement bus station.
Rotherham United is in the early stages of a plan to turn part of the Guest & Chrimes building into a trampolining centre.
The council said other short-term measures to improve footfall included a review of licensing on-street promotions, the move to ban spitting and walkabouts with businesses to identify areas needing extra cleaning.
Parking charges on Forge Island are £1 for two hours, £2 for four hours and £3 all day. Red zone spaces are free for two hours.