Hydro Development (HDL) said Solid Energy had lodged a notice of appeal against consents for its Stockton Plateau Hydro Scheme.

The move has been signalled by state-owned Solid Energy, which wants to use the water for its own scheme.

HDL won resource consent to build its scheme, allowing the company to harness tributaries of the Ngakawau River.

The plan consists of using polluted water from the coal mines on the Stockton Plateau and channelling it through tunnels, reservoirs and power stations, to generate power before discarding it in an ocean outfall offshore.