The Local Democracy Reporting Service reported signs were being put up pointing people to alternative public toilets in Plymouth Market and Drake Circus.
The council fenced off the area in October 2025 to investigate the extent of the live utilities beneath the surface and get a feel for the ground conditions.
The regeneration of Armada Way began last October with 62% of the funding from external sources including government grants with the work said to be on time and on budget.
As part of the urban park, an amphitheatre and fountain area have opened as well as new green spaces, gardens, wildlife, and picnic areas. The project also includes more than 200 trees, new cycle paths and a giant play area, plus a host of water features.
The council said the current sewer system was not designed to deal with current or future demands of modern plumbing in residential and commercial properties.
The new Armada Way toilets will be renovated and the whole project is set to open in the summer, the council added.