Volume One 5. Allocation of Public Resources not shift the interface. A warning system is also in place to detect signs of salt water intrusion. Limits will be imposed by way of conditions on resource consents, and due to the nature of the potential effects of abstraction in the coastal area, restrictions will be based on reducing actual water taken rather than that allocated through the resource consent. Allocation of water [R] Policy 5.2.13 – Limit the total amount of water available to be taken from any freshwater management unit and avoid allocating water (through the resource consent process) beyond the limit set. Policy B1 NPSFM requires the Council to set environmental flows and/or levels for all FMUs. These levels include an allocation limit, a limit on the total amount of water that can be allocated within any FMU. Policy 5.2.13 gives effect to Policy B1 of the NPSFM by establishing allocation limits for each FMU through regional rules. For those water resources that have multiple allocation classes, an allocation limit is set for each class. Policy B5 of the NPSFM specifies that the Council must not make decisions that will likely result in future over-allocation. This means that the Council cannot continue to allocate water once the cumulative level of allocation from a FMU reaches the allocation limit set in rules. For this reason, any further allocation of water from the FMU should be avoided (unless explicitly provided for in another allocation class). [R] Policy 5.2.14 – Where there is insufficient environmental data to establish an allocation limit for a river, use a default allocation limit of 50% of the seven day mean annual low flow for rivers with a mean flow greater than 5m³/s and 30% of the seven day mean annual low flow for rivers with a mean flow less than 5m³/s. Policy B1 NPSFM requires the Council to set environmental flows for all FMUs, which includes allocation limits. The Council monitors flow in rivers from which there is a demand for water, but does not necessarily monitor flow in rivers from which there is no or little demand. In some cases, this means that there is insufficient hydrological information and other relevant environmental data to establish a specific allocation limit for the river. In these circumstances, a default has been applied to meet the requirements of the NPSFM. The relevant allocation limit in these circumstances will be applied as a condition of resource consent. [R] Policy 5.2.15 – Protect flow variability of rivers by using, where identified as necessary, a system of flow sharing that splits allocation of available water between instream and out- of-stream uses. The establishment of environmental flows for rivers affords protection to natural and human use values by establishing the minimum flow requirements for those uses and values. In some circumstances, flow variability above the minimum flow may also be important to sustain the natural and human use values supported by the river. Where this is the case, a system of flow sharing is used to proportionally allocate the water above the minimum flow to both abstractive users and natural and human use values. In other words, a proportion of the water available within the allocation class can be abstracted, while a proportion must be left in the river. The water left in the river will ensure that the taking of water does not reduce river flow to the minimum for an extended period of time. The detail of the flow sharing is river specific and is reflected in the allocation limits and thresholds for taking water in each of the allocation classes. 5 – 7