The volunteer group had focused on improving stream and river water quality through riparian fencing, stream bank planting and wetland protection plus monitoring aquatic diversity in Western Bay waterways.
The $250,000 was part of a $500,000 grant to the Uretara group this year for its work across five catchments in the Kaimai 'Hills to the Ocean' project - Tahawai, McKinney, Uretara, Te Rereatukahia and Te Mania.
The balance of the $500,000 came from the district council ($50,000) and Bay of Plenty Regional Council ($200,000).
Urban development, intensification of land use and changing farming practices have caused accelerated stream bank erosion, sedimentation and stream pollution throughout the five catchments.
Landowner involvement was critical the group's work due to the catchment waterways flowing through private land.
Estuary Managers group chairman Lawrie Donald said the funding was an outstanding result and he was immensely proud of the group's dedication.
"This level of funding is very unusual for community groups and will enable us to accelerate the catchment work we have been undertaking for many years to come."
Western Bay Council community relationships adviser Glenn Ayo said the success of the group was evidence that the combination of selfless volunteer effort and Mr Jenk's guidance was producing quality results.
The estuary managers' funding was part of $44 million spread across 33 freshwater improvement projects for 100 rivers and lakes throughout New Zealand.
The Bay of Plenty region received $8.25 million distributed among the group ($250k); Bay of Plenty Regional Council's Rangitaiki River wetland restoration project ($1.5m) and Rotorua Lakes Council's Lake Tarawera sewerage reticulation ($6.5m).