Houseboat owners within a riverboat village could be cut adrift if developers fail to offer them fresh access to the land they are moored to.
Tideway village, a cluster of boats moored by Nine Elms Lane, has been battling for three years with developers St James to remain on the site, set to become flats.
As St James own the land, boat owners require permission to walk across the site to gain access to their homes, and this agreement is set to expire.
St James recently renewed the licence for one boat until October, with plans in place to also renew for the other two boats.
But houseboat owners fear time is running out and believe St James is pushing the 22 tenants out to open the river-side view when the development is complete.
David Waterhouse, owner of the two houseboats, said: "We are almost like a little Venice on the river, we have got beautiful gardens on the boats down here.
"It would be a complete loss to London if this way to go, it is a completely unique fixture of the river which is nude of features."
Tideway Village is made up of two houseboats and entertainment venue Battersea Barge in an inlet dock, while other boats are moored to Nine Elms pier.
An ongoing petition to keep the boats has gained more than 2,000 signatures, with the owners claiming they feel neglected by the lack of support from Wandsworth Council.
A spokesperson for St James said: "St James wishes to work with the Riverboat community to ensure a vibrant river frontage, which opens up the outlook onto the river for all concerned, contributing to the new public river walk and Pocket Park, within three acres of open space on the new development.
"We consider the new river walk as an important piece of public realm for the whole of Nine Elms and want to open up views of the Thames for all using the river walk, as we believe this will help create a strong sense of place."