Land use such as agriculture, forestry and urban expansion increases the level of contaminants, including nutrients, heavy metals and sediment, entering our waterways. This can have detrimental effects on water quality. 

Diverting, controlling and extracting water all change the natural flow in, and between, waterways. This can impact freshwater species and ecosystems. 

Water quality in rivers across Otago shows a clear spatial pattern related to land cover and land use. Water quality is best at river and stream reaches located in high or mountainous areas with predominantly native vegetation cover. These sites tend to be associated with the upper catchments of larger rivers (for example, Clutha River/Matau‐Au, Taieri River and Lindis River) and the outlets from large lakes (for example, Hāwea, Whakatipu and Wānaka). Water quality is generally poorer at sites located on smaller, low-elevation streams that drain pastoral or urban catchments. 

The government is committed to stopping further degradation and to restore our waterways to a healthy state within a generation. As part of this commitment, in August 2020, the “Action for Healthy Waterways” reform package was announced. 

The healthy waterways reform package includes: 

• New National Policy Statement for Freshwater Management (NPS-FM 2020), replacing the current NPS-FM 2014 
• New National Environmental Standards for Freshwater (NESFW) 
• New stock exclusion regulations under section 360 of the Resource Management Act 1991 (RMA) 
• Amendment to the Resource Management (Measurement and Reporting of Water Takes) Regulations 2010; and 
• Changes to the Resource Management Act 1991 to require freshwater modules in farm plans in the future. 

Some of the rules and regulations apply now, while there is a longer timeframe for others.