Source Water Risk Management Areas (SWRMAs) are becoming an increasingly important part of New Zealand’s drinking water safety framework, and for rural communities in particular, they can have real and lasting impacts on how land is used. These areas are mapped around drinking water sources, whether bores, springs, rivers or lakes, and are designed to identify and manage activities that could contaminate those supplies. They are needed because protecting source water is the first and most critical barrier to ensuring safe drinking water. SWRMAs give councils and large water suppliers serving more than 500 people a clear and consistent way to manage risks from land use, spills, microbial contamination and persistent pollutants. Current regulations require these larger suppliers to identify SWRMA zones and manage risks within them to ensure water supply safety. Smaller drinking water suppliers are not currently required to define SWRMAs, but they still need to manage risks to protect their source water.

While the purpose of SWRMAs is straightforward, their practical implications can be significant, especially when a mapped area extends onto private rural land. For landowners, an SWRMA can introduce limits on the types of activities that can occur within certain distances of a well or waterway used for drinking water. This might include restrictions on effluent disposal, chemical storage, certain farming practices or earthworks. If a water supply is new, or changes in a way that alters its capture area, for example an increased rate of take or a deeper bore, then the SWRMA may also need to change. When that happens, the water supplier must approach any newly affected landowners. This is because defining a protection area across private property often requires landowner permission and may impose constraints on future land use. Aqualinc has been involved with several projects where councils have had to negotiate with rural landowners to define SWRMAs and manage activities within them.  These conversations can be challenging for all involved if expectations are not clear from the outset.

From a water supplier’s perspective, getting SWRMAs defined robustly is essential for meeting regulatory expectations and protecting public health. Suppliers need confidence that the mapped areas accurately reflect how water and contaminants moves through soil, groundwater and surface catchments, and that activities within those areas are properly identified and managed. But from a landowner’s perspective, the accuracy of the technical assessment is just as important. An overly conservative or technically flawed assessment of the SWRMA’s required size and shape can unnecessarily restrict land use, reduce flexibility for farming operations or affect development plans. This is why councils and their consultants must ensure that the science behind SWRMA delineation, , travel time estimates and catchment mapping, is robust and defensible.  In some cases, detailed groundwater modelling rather than default methodologies may be required to reach a robust conclusion.

As rural communities continue to grow and urban areas expand onto land that was previously farmed, requiring new drinking water sources to be established, SWRMAs will remain a key part of ensuring safe and reliable supplies. But with that comes a responsibility to balance protection of source water with fairness to landowners whose properties fall within these areas. For those living and working on rural land, it is worth being aware of proposed water supply developments nearby, especially where new bores are planned close to property boundaries. Early engagement, sound technical work and clear communication can help avoid issues later and ensure that both safe drinking water and productive rural land use can continue side by side.

Groundwater Management Farmers and Growers