Cupwith Reservoir, above Marsden, near Huddersfield, was built in the 1800s to supply mills but is no longer used.
Plans before Kirklees Council involving engineering works at the remote reservoir would see the water reduced by two-thirds.
Thirty objectors have said the work could damage ecology and views by a planning report has concluded that the proposal would not have a “significant adverse impact on the local ecology”. The report also concludes that the plans would not damage the character of the green belt moorland landscape.
The applicant, Rosscroft Ltd, wants to reduce the volume of water by creating a new concrete overflow channel which would allow the reservoir to overflow at a lower level.
The company provided an ecological assessment which concluded that species diversity in the vicinity of the reservoir is low and although some of the current vegetation may be lost temporarily, it should grow back.
The assessment also said that any disturbance to habitats would be temporary.
The council says planning permission is not required to drain the reservoir, only for the engineering works. Members of the council’s planning committee will meet tomorrow to discuss the plans.
Councillors will be told that the scheme can be given conditional approval subject to further scrutiny by planning officers.
The report concludes: “This proposal would result in a substantial reduction in the area of the current reservoir. However, it is considered that subject to the inclusion of specific planning conditions to control operations during the construction of the new overflow system and the subsequent restoration of the site, this proposal would not have a significant adverse impact on the local ecology of the area.”