The Tiraumea sub-catchment:
- is 94,000ha in area,
- land use is 79% sheep and beef, 17% forest (native and exotic), 3% dairy,
- has few popular swimming spots,
- has one site of rare/threatened native fish,
- the Mākuri River, a significant tributary of the Tiraumea River, is an important trout fishery and spawning area,
- contains significant wāhi tapu and customary fisheries throughout its length. It is of major significance to Rangitāne O Manawatū,
- contains seven high priority bush and two high priority wetland sites,
- includes the Tawataia-Mangaone and Ihuraua schemes, and
- Te Kāuru (Manawatū River Eastern Hapū Collective) Ngāti Pakapaka, Ngāti Mutuahi, Ngāti Hāmua, Ngāti Te Kauparangi, Ngāti Koro are the hapū of this sub-catchment.
The water quality of the Tiraumea sub-catchment is characterised by very high suspended sediment loads, and high phosphate and nitrate levels in the main river. Pathogen levels are typically safe for swimming. Sediment and nutrient levels are the result of non-point source run-off.
THE WATER QUALITY STATE IS EXPLAINED BY:
- this sub-catchment contains approximately 14,000ha of unprotected erosion prone land (36% of the unprotected erosion prone land in the entire Manawatū Catchment) and contributes 34% of the total suspended sediment load to the Manawatū Catchment,
- there are no consented discharges to water in the sub-catchment,
- there are 12 consented dairy shed effluent discharge consents, all of which are discharges to land. Inspections so far this season show 100% compliance in this sub-catchment, and
- the exact level of progress towards the Dairying and Clean Stream Accord targets (around stock exclusion from waterways, stock crossing, and nutrient management) by dairy farmers in this sub-catchment is unknown, but there is some riparian fencing and stock crossings (bridges and culverts). Farmer surveys in the Manawatū-Whanganui region indicate the majority of Dairying and Clean Stream Accord targets are being achieved.
- One man-made barrier is having a moderate to high impact on native fish migration,
- public access to the Tiraumea River is limited, but access to the Mākuri River is good. Excessive willow growth along the main stem of the Tiraumea River is a major barrier to access and also impedes flows and contributes to sediment issues,
- only 43% of high priority bush remnants and 50% of high priority wetlands are protected, and
- the water quantity resource of the Tiraumea sub-catchment is 89% allocated. All major takes are metered and automatically monitored.