The Ministry of Fisheries has given final approval for a 520-hectare shellfish farming space at Wilson's Bay in the Firth of Thames.
The outcome follows a preliminary consent decision made six months ago.
Ministry aquaculture manager Dan Lees says though there will be some impact on commercial set net fishing, he is satisfied the marine farm will not unduly affect sustainability.
The marine farm will occupy nearly 1800 hectares, of which about 1300 hectares will be access-ways between farm blocks.
The regional council must now identify 20% of the aquaculture space for allocation to iwi and process resource consents for other applicants.