The Manawatū-Whanganui Region has 40 estuaries scattered along its coasts. Twenty-five spill out into the Tasman Sea on the west coast, and 15 flow into the Pacific Ocean on the east coast. These environments make up almost ten per cent of all estuaries in New Zealand and provide valued habitats for a diverse range of flora and fauna. They are also great places for recreational activities such as swimming, kayaking, fishing, or bird-watching.
Horizons Regional Council monitors estuaries around the region to identify and track changes in their sedimentation levels (three estuaries), water quality (seven estuaries), and habitat health (two estuaries). Manawatū-Whanganui estuaries handle the effects of deforestation, rural land use and discharges from industry and urban wastewater in different ways. Initial monitoring shows over half of these estuaries have exhibited formidable resilience and are considered low to moderately vulnerable to excess nutrient and sedimentation loads.