Water conservation important as water levels drop

As the dry weather continues and water restrictions come into play throughout the Region, Horizons Regional Council reminds consent holders to comply with their water take consents and for the rest of the public to take heed of city and district water restrictions. 

“Fortunately, up until October the year has been wet - providing an opportunity for groundwater aquifers to recharge, some to a level where they are higher than the previous year,” says Horizons science and innovation manager Abby Matthews.
“This was a good start to what is becoming a very dry summer that will provide challenges to some groundwater users due to falling levels under the current conditions. Shallow and artesian bores are most at risk.”
Ms Matthews says being conscious of water use extends to the urban areas as well as rural users.
“Large urban water supplies have consents that set out how much water they can take and when they have to reduce that amount. While never required to switch off completely, city and district councils usually have step-down restrictions, meaning they have to reduce the overall volume they abstract and treat.
“This means they have to manage the demand by asking citizens to reduce their water use and conserve water. Essentially, the town supply reduces their take volume to meet the conditions of their consent and that in turn means that the town-folk have to play their part by reducing their water consumption.”
Ms Matthews says for town water supplies that have some storage, sometimes the levels of restrictions they put on might be more gradually applied because they have the buffer of storage.
“However, ultimately they need to manage to be able to continue to supply the town over as long a period as possible.”
Reasonable water allocation use guidelines are set out in Horizons’ One Plan to guide resource consent decision making. However, takes for activities such as irrigation require more information including setup plans, area of land to be irrigated, crop type, and irrigation schedule.
“Horizons’ approach is that all water abstractions require the installation of a water meter by an accredited installer. Abstractions that take at a rate of 5 l/s or greater also require reporting of water use data back to Horizons via telemetry,” says Ms Matthews.
Minimum flow restrictions on surface and water abstractions are set to minimise the impact of human activity on instream habitat. While river flows naturally vary with seasonal and climatic change, flows in streams and rivers are decreased more rapidly and held at low levels for longer than might naturally occur by out-of-stream water use.
“Uncontrolled this may mean that river ecology and water quality is adversely impacted. The minimum flow levels that Horizons use are carefully determined on a river-by-river basis, considering a range of factors including instream values, water quality, water demand and localised hydrology.” 
Ms Matthews says controlling non-essential takes at low flows also helps provide greater certainty for essential water uses such as domestic and stock water supply.
“Horizons encourages consent holders to be mindful of their water use as further restrictions could come into place over the next few weeks. We appreciate that restrictions can cause stress, particularly to our rural communities.
“We encourage farmers to contact their Rural Support Trust or Federated Farmers representatives for support,” she says.

Water take consent conditions include:

  • If you take water from a stream, river, or riparian bore you may have a requirement in your resource consent to reduce/cease abstraction when the river flow reaches a restriction level. 
  • Should the river be at or below your consented minimum flow restriction level, you must restrict or cease abstraction (according to your consent conditions) for that day.
  • River flow information can be checked on Horizons' Environmental Data webpage, by logging into Horizons’ WaterMatters webpage (need to be registered) or by phoning 0508 4 FLOOD (0508 4 35663). 
Low flows and higher temperatures can also contribute to an increase of toxic algae growth in rivers and streams. This algae occurs naturally in waterways with good water quality most of the time and don’t cause any issues. However, during a summer such as the one we are currently experiencing, cyanobacteria can form extensive blooms which can be toxic to human and animals.
As part of our swim spot monitoring programme we test for cyanobacteria, with the results published on the Horizons and Land Air Water Aotearoa (LAWA) websites on a weekly basis.