ORC monitors water quality and ecology in rivers and streams. The results can show the state of the environment for a location. Water quality in the Upper Lakes is monitored at 23 river/stream sites and three lakes, while ecological monitoring is done at nine river sites and nine lake sites. 

Monitoring results show that water quality in the Upper Lakes is the best in Otago. Only a couple of streams in urban areas experience high E. coli counts due to stormwater run-off and wildfowl. Clarity is reduced in some of the glacier-fed rivers, but this is a natural process. 

The lake monitoring sites at Wānaka, Hāwea and Whakatipu also have excellent water quality results. However, these sites show persistent growth of the introduced algae Lindavia intermedia, which produces a glue-like substance called lake snow. Although not harmful to people and animals, it is a nuisance and thrives in lakes with very low nutrient levels such as those in the Upper Lakes 

Introduction to water quality

Upper Lakes Rohe water quality summary

Upper Lakes Rohe science Summary

Lake levels and water abstraction limits for Lake Wanaka and Lake Whakatipu

In its new Land and Water Regional Plan ORC must set environmental outcomes for the freshwater values identified in the Upper Lakes rohe. An environmental outcome statement describes the desired future state that communities in the Upper Lakes rohe and tangata whenua would like to see for a specific value.  

The environmental outcome statements are very similar across all FMUs and rohe in Otago, which reflects the fact that the aspirations that tangata whenua and the different communities have for the environment are largely consistent across the region. Table 1 sets out the draft environmental outcomes for the Upper Lakes Rohe.

Table 1: Draft environmental outcomes

¹*Asterisk indicates that the baseline state of these compulsory attributes is not known, but monitoring is now being undertaken.

Attributes are indicators that we can measure and monitor. Attributes tell us about the state of a river or lake. A target attribute state (TAS) is the state that an attribute must achieve to make sure that an environmental outcome is met. The timeframe for achieving the TAS for each FMU is set by the environmental outcomes for the FMU.  For the Upper Lakes rohe, the environmental outcomes are to be achieved by 2030. By monitoring attributes and comparing their baseline state with their TAS we learn how well how well we are on track towards achieving the environmental outcomes for this FMU or rohe. 

While the environmental outcome statements are largely consistent across Otago, baseline states and TAS are usually specific to each FMU and rohe. Attributes for each value and baseline states for those attributes have been identified along with trends derived from the Otago Regional Council's State of the Environment (SoE) monitoring data. 

The baseline state and TAS for the Upper Lakes rohe are in the map below.

Zoom into an area and view the various locations of proposed monitoring sites in an area(s).

Select the yellow dot representing a proposed monitoring site to see the Target Attribute States.

You can further select the Target Attribute States table to view a larger version of the table.

(Note: If you are on a mobile device, tap on the arrow next to the 'X' icon for the table to show.)

National direction requires Council to set limits as rules or action plans (as appropriate) to achieve the environmental outcomes. This can be done at a region-wide level or at FMU/rohe level. The draft region-wide rules are set out in different briefing papers, including the briefing papers Primary Production, Wastewater, Stormwater, Earthworks, Water Quantity and various others.

For the Upper Lakes rohe, there are no additional rules needed to make sure the environmental outcomes for this rohe are achieved.

The Upper Lakes Rohe chapter will also include take limits and environmental flows and levels for rivers, lakes and aquifers in this rohe.  

Take limits reflect the total quantity of water that can be taken, dammed or diverted from a stream, river, lake or aquifer. Once the combined rate of take for all consented water takes, diversion or damming activities from a water body matches this take limit no further water can be allocated in new consents.  

Environmental flows (for rivers or streams) or environmental levels (for lakes and aquifers) include minimum flows or levels that when reached all consented (and some permitted) takes, diversions and damming activities must cease. These restrictions on water taking, diversions or damming activities typically occur during dry periods and are needed to make sure after important values, such as threatened fish, drinking water supply or mahika kai (food and resource gathering) values, are looked after. 

Environmental levels and take limits for the lakes in the Upper Lakes Rohe are shown in the table below. 

Given their high naturalness values, it is proposed that a narrative take limit is set for most of the natural lakes in this rohe. This limit will prohibit any new takes, damming or diversions that could impact water levels of these natural lakes (except for takes that are permitted under the Resource Management Act 1991) and will ensure they will continue to behave in their natural or near natural state. Specific take limits and levels are proposed for Lake Wānaka and Lake Whakatipu. These limits will allow for more water to be allocated from Lake Wānaka and Lake Whakatipu and their tributaries, recognising that these water bodies are located near fast-growing urban settlements. However, the proposed take limits are small enough to avoid any changes to the lakes’ hydrology and specific minimum levels are proposed for both lakes to restrict water takes when lake levels are low.  

Lake Hawea will continue to be managed in accordance with its consented lake level conditions. Any takes from this lake will be subject to the take limits that apply to the Clutha River/Mata-Au take limit. 

Table 2: Environmental levels and take limits for lakes

Environmental flows and take limits for the Upper Lakes rohe’s rivers and streams are shown in the table below.  Take limits and environmental flows are often set as a percentage of the 7-day Mean Annual Low Flow (7-day MALF).  The 7-day MALF is a flow statistic that provides an indication of how low the flow gets in a typical year. 

For smaller rivers or streams with a mean flow of 5,000 litres per second or less, such as the Kidds Creek and Quartz Creek, a total take limit is set as 20% of the 7-day MALF. For larger rivers with a mean flow of more than 5,000 litres per second, such as the Matukituki River and the Rees River, a larger take limit is set at 30% of the 7-day MALF.  

Restrictions on water takes, diversions and damming activities in catchments of smaller rivers or streams are triggered when flows are at 90% of the 7-day MALF, whereas for larger rivers these restrictions will not kick in until flows are at 80% of the 7-day MALF.   

Bespoke limits and environmental flows are proposed for Bullock creek.  

Table 3 provides estimates of the actual minimum flows and take limits for different catchments based on the default method using the best available information to determine the 7-day MALF of each catchment. The numeric minimum flows and take limits will not be included in the LWRP. Instead, the LWRP will refer to the relevant % of 7-day MALF.

Table 3: Rivers managed by default minimum flows and take limits