Archive: Waiology June 2014

Water quality models – are they good enough for management?

Waiology • Dec 02, 2013

• CLUES,
• modelling,
• nitrate,
• Overseer,
• Water quality

By Sandy Elliott Water quality models are making their way to a farm or catchment near you – so what are they, and how good are they? Models are being used in New Zealand to address water quality impacts of land use from national to farm scales. At national scale, the CLUES model was recently linked to a … Read More

Emerging organic contaminants: A threat to New Zealand freshwaters?

Waiology • Nov 29, 2013

• emerging contaminants,
• organic contaminants,
• synthetic chemicals,
• wastewater,
• Water quality

By Sally Gaw Emerging organic contaminants are a burgeoning and extremely diverse class of contaminants that are not routinely monitored and that have the potential to have adverse ecological and human health effects. Emerging organic contaminants (EOCs) include both naturally occurring and synthetic chemicals. Many of these contaminants may have been present in the environment for a long time … Read More

Nitrate in Canterbury groundwater

Waiology • Nov 27, 2013

• Canterbury,
• Groundwater,
• nitrate,
• Water quality

By Carl Hanson Nitrate concentrations in Canterbury groundwater have been prominent in the media recently. Headlines have included phrases like “ticking time bomb”, “scaremongering” and “freaking out much of Canterbury”. What I want to do in this article is to present the state of nitrate concentrations in Canterbury groundwater, and the trends we see in those … Read More

Nuisance periphyton – too much of a good thing

Waiology • Nov 25, 2013

• algae,
• cyanobacteria,
• Didymo,
• Health,
• nutrients,
• periphyton,
• Water quality

By John Quinn Periphyton is the name given to the community of algae that grows on river and lake beds, and it has a Dr Jekyll and Mr Hyde reputation. As thin films and short/sparse filaments – the good Dr Jekyll – it is an important fuel at the base of healthy aquatic food webs, turning nutrients and sunlight … Read More

Overcoming obstacles to setting water quality limits

Waiology • Nov 22, 2013

• Canterbury,
• limit-setting,
• management,
• Water quality,
• zone committees

By Ned Norton and Helen Rouse In the previous Waiology series on Water governance, we referred to the National Policy Statement for Freshwater Management (NPSFM) (2011) requirement to set limits for water quantity and quality. So, how are councils getting on with limit-setting? In May 2012 we surveyed planners for regional councils to find out how their … Read More

Science and policy merge in water plan

Waiology • Nov 20, 2013

• governance,
• limit-setting,
• management,
• policy,
• Water quality

By Paul Reynolds Recently the government released proposals for a national framework for setting freshwater objectives, including bottom lines for ecosystem and human health (for secondary contact). It has had an unusual reaction. For the first time in my memory, we have had stakeholders from all quarters pretty much in strenuous non-disagreement with one another – in support of … Read More

Monitoring the diversity of NZ groundwater quality

Waiology • Nov 18, 2013

• Aquifers,
• e coli,
• Groundwater,
• nitrate,
• Water quality

By Magali Moreau, Chris Daughney and Zara Rawlinson To date, more than 200 aquifers have been mapped across the country. These aquifers vary widely in their volumes, depths, host-rock lithologies, related geological structures, water circulation pathways and water age. Our knowledge of the individual characteristics of these aquifers grows as we gather more data through our active monitoring networks. Read More

Managing nitrogen in the Lake Taupo catchment

Waiology • Nov 13, 2013

• Lake Taupo,
• management,
• modelling,
• nitrogen,
• Overseer,
• Water quality

By Bill Vant and Jon Palmer More than 10 years ago, the Waikato Regional Council became concerned about the effects of increasing catchment loads of nitrogen on the water quality of Lake Taupo. Calculations showed that most (>90%) of the manageable nitrogen entering the lake came from areas of pasture in the catchment. A variation to the Waikato Regional … Read More

Why freshwater management needs to include estuaries

Waiology • Nov 11, 2013

• estuaries,
• limit-setting,
• management,
• Water quality

By Malcolm Green There is a widespread view that cumulative effects – those effects that build up over time or that occur in combination with other effects – are the Achilles heel of the Resource Management Act. Back in 2010, the Land and Water Forum, echoing previous legal commentary, argued that limits are the solution: “without limits it is … Read More

Proposed national bottom lines for water quality

Waiology • Nov 08, 2013

• management,
• Water quality

By Daniel Collins The Government recently released a new round of freshwater reform proposals. A significant part of them included additions to the National Policy Statement for Freshwater Management with regards to water quality. The NPSFM currently directs Councils to undergo a process of setting limits for water quality degradation, but neither the process nor consistent numerical targets … Read More