The Lower Manawatū sub-catchment:
- is approximately 50,000ha in area,
- land use is 54% sheep and beef, 25% dairy, 11% forest (native and exotic), and 6% urban,
- has a number of popular swimming spots,
- contains historic Rangitāne O Manawatū wāhi tapu and customary fishery areas throughout, along with mahinga kai, and kāinga sites. There are also shared hapū/iwi arrangements with Ngāti Whakatere, Ngāti Ngārongo, Ngāti Takihiku, Ngāti Hinemata, Ngāti Kauwhata and Ngā hapū O Hīmatangi in the lower reaches of the mid-Manawatū river catchment. This includes a number of Ngāti Raukawa fishing grounds, and fish habitats,
- has three sites of rare/threatened native fish, including Kāhuterawa Stream which is a regional native fish hot-spot,
- is an important trout fishery and spawning area,
- contains 9 high priority bush and 1 high priority wetland sites, and
- includes parts of the Lower Manawatū scheme and the Manawatū Drainage scheme.
The water quality of the Lower Manawatū subcatchment is characterised by high suspended sediment loads (inherited from further upstream in the catchment), and high phosphate and nitrate levels. The high nutrient levels are a combination of inputs from the upper part of the Manawatū Catchment, as well as non-point and point source inputs from within this sub-catchment. Palmerston North sewage is the largest discharge in the Manawatū Catchment. Pathogen levels are generally safe for swimming.
THE WATER QUALITY STATE IS EXPLAINED BY:
- this sub-catchment contains approximately 100ha of unprotected erosion prone land and is contributing a very low amount of the total suspended sediment load to the Manawatū Catchment,
- there are 55 consented discharges to water in the sub-catchment, three of which are considered significant. These are: Palmerston North sewage, Longburn sewage, and Fonterra (Longburn). Manawatū District Council is currently assessing the viability of connecting
Longburn sewage into the Palmerston North Waste Water Treatment Plant. New Zealand Pharmaceuticals have recently started piping their discharge to Palmerston North Waste Water Treatment Plant. The compliance rate of he discharges monitored is 89%,
- there are 87 consented dairy shed effluent discharge consents, all of which are discharges to land. These consents will be assessed for compliance before the end of the season, 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 Manawatū-Whanganui region indicate the majority of Dairying and Clean Stream Accord targets are achieved.
- 6 man-made barriers are having a moderate to high impact on native fish migration,
- public access to the Manawatū River and several of its tributaries is good due a network of walkways,
- only 11% of high priority bush remnants and none of the high priority wetlands are protected, and
- the water quantity resource of the Lower Manawatū sub-catchment is 79% allocated. This includes the significant water supply take from Turitea. All major takes are metered and automatically monitored.