The Upper Manawatū sub-catchment:
- is approximately 131,000ha in area,
- land use is 69% sheep and beef, 17% dairy, 13% forest (native and exotic)
- has many popular swimming spots,
- has eight sites recognised as significant aquatic habitat for rare/ threatened native fish
- is an important trout ﬁshery and spawning area,
- contains 6 high priority bush and 3 high priority wetland sites,
- includes the South East Ruahine scheme, the Eastern Manawatū sheme, and a large part of the Upper Manawatū Lower Mangahao scheme, and
- Te Kāuru (Manawatū River Eastern Hapū Collective) Ngāti Ruatotara, Ngāti Rangitotohu, Ngāti Te Opekai, Ngāti Marau, Ngai Tahu, Ngāti Parakiore, Ngāti Pakapaka are the hapū in this sub-catchment.
The water quality of the Upper Manawatū sub-catchment is characterised by high sediment loads, high nutrient (nitrate and phosphate) levels, pathogen levels in smaller tributary streams are regularly above safe swimming guidelines, and cyanobacteria is regularly detected at swimming spots. Non-point source run-off (from the land) contributes more than 98% of the total nitrate and 80% of the total phosphate load. Under low ﬂow conditions, point source discharges contribute approximately 10% of the nitrate and 66% of the phosphate.
THE WATER QUALITY STATE IS EXPLAINED BY:
- this sub-catchment contains approximately 10,000 ha of unprotected erosion prone land (26% of unprotected erosion prone land in the entire Manawatū Catchment) and contributes 29% of the total suspended sediment load to the Manawatū Catchment,
- there are 24 consented discharges to water in the sub-catchment, four of which are considered significant. These are: Dannevirke sewage, the Scanpower site sewage, Norsewood sewage, and Ormondville sewage,
- the major discharges in this area are fully consented at present i.e. none of these are currently undergoing consent renewal. The compliance rate of the discharges monitored is 79%,
- there are 150 consented dairy shed effluent discharges to land consents. Over the last 10 years all dairy shed effluent discharges have been diverted from water to land. The compliance rate of these consents so far this season is 82%, 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 extensive riparian fencing and planting, and stock crossings (bridges and culverts). Farmer surveys in the Manawatu-Whanganui region indicate the majority of Dairying and Clean Stream Accord targets are achieved.
- 15 man-made barriers are having a moderate to high impact on native fish migration within the sub-catchment,
- public access to the Manawatū River is good, but to its many tributaries is very limited,
- only 17% of high priority bush remnants and all high priority wetlands are protected,
- the length of river suitable for trout spawning is declining, and
- the water quantity resource of the Upper Manawatū sub-catchment is fully allocated, with the Raparapawai Stream being overallocated. All major takes are metered and automatically monitored.