Hollywood star Dame Helen Mirren has joined a campaign against the expansion of a waste water plant in the Highlands.

Dame Helen is said to have been alarmed by Scottish Water's plans to redevelop the treatment facility near Ardersier.

The Queen star married husband Taylor Hackford in the small fishing village on the Moray Firth in 1997.

More than 1000 people have signed a petition against the £11m waste plant, which Scottish Water says is essential to the development of 5000 new houses at nearby Tornagrain.

Campaigners against the development say there was a "lack of consultation" over the plan and have raised concerns over its impact on traffic, tourism and the environment.

Dame Helen is the second famous name to get involved in a battle over a Scottish Water scheme in recent weeks.

Environmental activist Erin Brockovich branded plans to add a cocktail of ammonia and chlorine to the drinking water of 10,000 Scottish homes in the Spey Valley a "dirty trick".

Scottish Water insisted its chloramination plans for the supply to thousands of homes will improve the situation by reducing the amount of chlorine and introducing ammonia into the water.

A spokesman for Scottish Water said: "We are investing more than £11m in a package of essential improvement projects to upgrade the waste water infrastructure in the Ardersier and surrounding area.

"The significant investment, which includes the upgrading of the Ardersier waste water treatment works, will protect the environment of the Moray Firth while supporting the economy of the A96 corridor and helping to enable development at Tornagrain, which is now progressing.

"This is not a new proposal - these projects were proposed around six years ago when engagement with the community first took place.

"Planning permission for the upgraded waste water treatment works was granted in June 2011 and it is important to understand that this is on the site of our existing facility, which already takes flows from the existing Tornagrain village.

"We met with the Ardersier Community Council earlier this month to provide an update on the investment programme, and at their request, we have organised an information event to be timed with their next meeting so that they have the opportunity to discuss the projects immediately afterwards.

"We also met with local councillors and have sent letters to households in the area to invite them to attend the information event.

"We look forward to taking this opportunity at the information event to allay concerns, answer questions and provide clarification on the issues that are being raised. In particular, we can provide reassurances on how we are working closely with Highland Council on all road and traffic management matters."