In a statement against a large-scale irrigation project, Greenpeace protesters used six tonnes of dairy sewage to block two main entrances to the Molesworth St offices.
Earlier this year there was some speculation about the fund being a potential investor in the dam, however, ACC has repeatedly refused to confirm or deny its link to the project.
Greenpeace's agriculture campaigner Genevieve Toop said the multi-million dollar project would pollute "our precious rivers".
"Millions of tonnes of pollution end up in our rivers via cow piss already. And this pollution will only get worse if government departments like ACC throw taxpayers' money at irrigation schemes like Ruataniwha that expand the industrial dairy sector."
She called for the Government to look towards ecological farming methods.
The Ruataniwha water storage project that entailed an 83m-high dam on the upper Makaroro River, and was being driven by the Hawke's Bay Regional Council, has a projected cost of almost $900 million.
-Â NZ Herald