Steve Humphrey, Medway council's assistant director of regeneration and environment, said a deal with Wimpey was imminent "We literally expect to sign the deal within the next few weeks and then Wimpey will submit their planning application," he said.
Some of the delay is because Berkeley, originally selected as developer in March last year, pulled out seven months later, blaming site complications that affected the value of the land.
Humphrey said the cost of reclamation work, significant funding gaps and the construction of a new river wall had made the deal difficult to resolve, and he admitted that there was a risk that Wimpey would pull out.
He said: "This is going to be a really great project with high-quality urban design on a prime site opposite Rochester High Street, the castle and the cathedral. If we can't get this kind of site developed then we really are in trouble."
The 30 ha site on the Medway riverbank in Rochester has been the site of a gas works, aggregate factories and waste deposits.
Medway council has spent £19m acquiring two-thirds of the largely derelict site. The remaining land will be acquired by the end of the month through compulsory purchase orders.
Wimpey plans to building 1750 houses, a hotel and conference centre, primary school and retail, leisure and office space.
About 20% of the homes will be affordable housing for key workers and the retired.
Humphrey expects planning permission to be granted by January, with work on the site to begin next summer. The scheme is expected to take 10 to15 years to complete.
The Rochester Riverside scheme became a flagship regeneration project when it was announced more than two years ago. The council's development brief included a submission by Lord Rogers of Riverside, the chairman of the urban taskforce.
He said the project was "what the urban renaissance is all about".