Objectors to plans by the National Trust to flood 37 acres of grassland in Cornwall have presented a petition to Caradon District Council.
Caradon District Council rejected the original proposals in 2002.
The trust says flooding the banks of the River Tamar near Cotehele will create a unique wetland and reed bed.
However protesters argue that it will ruin part of an Area of Outstanding Natural Beauty (AONB).
They are calling on the council to throw out the proposals as it did three years ago.
The National Trust re-submitted its controversial plans in May.
Under the proposals, a riverbank would be breached in three places to allow water on to about 35 acres of agricultural land to help form a reed bed.
At first, the area would be turned to mud by the flooding. The reed bed would appear over a period of between 10 and 20 years.
The National Trust said the area would become an important habitat for rare animals such as the water vole. It said it also planned to put in a walkway to allow public access.
The trust wanted to flood the area three years ago but was turned down by Caradon District Council because of concerns about the effect on boats navigating the River Tamar.