Hunter River Salinity Trading Scheme Working together to protect river quality and sustain economic development A world-class scheme for protecting waterways The NSW Government’s Hunter Before the scheme there was River Salinity Trading Scheme significant conflict between leads the world in using economic primary producers and mining instruments for the effective operators. Discharges from protection of waterways. The industry increased salt levels in scheme has been responsible for the river at times making the restoring the waters of the Hunter water unsuitable for irrigation. to an unprecedented level of Primary producers responded by freshness. Water salinity1 is more seeking tighter regulation of Photo: DIPNR stable and lower—the river is now emissions. To address strong as fresh as many bottled mineral community concerns about new waters. discharges, new mine proposals were facing extremely high costs. A community working The scheme allows agriculture, together to protect mining and electricity generation The scheme is a huge win for the to operate side by side, sharing entire Hunter River community. river quality and sustain the use of the river. Agriculture benefits from fresh economic irrigation waters while miners It wasn’t always like this. development. and electricity generators can make controlled discharges of excess waters. It protects the region’s most precious natural resource, provides for diverse interests to work together, and allows continued economic development, providing a secure future for the region. 1 Water salinity is estimated Electrical conductivity at Singleton 1980 to 2002 (monthly means) by measuring electrical conductivity. The more salty salinity target salinity water is, the more it mean Electrical Conductivity (mS/cm)(µS/cm) trial 2000 conducts electricity. 1800 Electrical conductivity is 1600 measured in microsiemens 1400 Regulation per centimetre (µS/cm). scheme 1200 start commenced Drinking quality water usually 1000 S/cm) measures between 600EC µ 800 and 1200EC. EC (mS/cm) EC ( 600 Since the scheme started, 400 river salinity has more 200 consistently been below the 0 salinity target. Jan-80 Jan-81 Jan-82 Jan-83 Jan-84 Jan-85 Jan-86 Jan-87 Jan-88 Jan-89 Jan-90 Jan-91 Jan-92 Jan-93 Jan-94 Jan-95 Jan-96 Jan-97 Jan-98 Jan-99 Jan-00 Jan-01 Jan-02 Jan-03 2 Photo: State Water Photo: DIPNR Photo: DIPNR MURRURUNDI Pages R Isis R Dart Hunter R Brook Munmurra R Merriwa R SCONE Lake Glenbawn UPPER MERRIWA SECTOR ABERDEEN ULAN MUSWELLBROOK Paterson R Lake Foy Liddell Brook Goulburn R Lake DENMAN St. Clair KERRABEE Glennies DUNGOG Ck Gungalwa MIDDLE Ck SECTOR SINGLETON Williams R Widden PATERSON Ck Martindale Ck LOWER SECTOR Black Hunter R Wollombi Ck Brook MAITLAND CESSNOCK UPPER SECTOR MIDDLE SECTOR NEWCASTLE LOWER SECTOR The Hunter River catchment The Hunter River drains the Also located in the valley are Human activities also impact largest coastal catchment in over 20 of the world’s largest on river saltiness. During New South Wales, covering coal mines and three power coal mining, salty water some 22,000 square stations, including Australia’s collects in mine pits and kilometres. largest electricity generator. shafts and has to be pumped out to allow mining The Hunter region supports a Salt occurs naturally in operations to continue. range of agricultural many of the rocks and soils activities including wineries, of the Hunter Valley. Some Electricity generation uses dairying, vegetables, fodder, of this salt is leached into large volumes of river water beef and horse breeding. groundwater and nearby for cooling. As this water rivers. evaporates, natural salt is concentrated in the water that remains. 3 How the scheme works The central idea of the Going with the flow The river is divided into scheme is to only ‘blocks’ discharge salty water Monitoring points along the river The water in the river is nominally when there is lots of are used to measure whether the divided into numbered blocks. A river is in low flow, high flow or block is a section of water that low salt, fresh water flood flow. flows past Singleton in a day. So, block 2003-198 is the block of in the river. When the river is in low flow, water that will flow past Singleton no discharges are allowed. This is when the river can best on the 198th day of 2003 (17 July). handle salt discharges because: When the river is in high flow, This block of water will flow past • large amounts of fresh water limited discharge is allowed— other points on the river on dilute the saltier discharge so controlled by a system of salt different days. the impact on the river is not as credits. The amount of discharge For each block, the scheme great, and allowed depends on the ambient operators continually monitor salinity in the river, so it can • through careful control, the the flow level and the ambient change daily. The total allowable mixture of river and discharge salinity and then calculate how discharge is calculated so that the water can be kept fresh to meet much salt (if any) can be added to salt concentration does not go water quality standards. the block (Total Allowable above 900EC in the middle and Discharge) so that salinity stays lower sectors of the river, or above under the target. 600EC in the upper sector. When the river is in flood, unlimited discharges are allowed as long as the salt concentration does not go above 900EC. Members of the scheme coordinate their discharges so that this goal is achieved. Example of discharge controlled by credits Hunter River flow categories (megalitres per day) 198 Discharge unrestricted Site A flood 10000 197 high flow low flow 196 Singleton 6000 Discharge with credits 195 194 4000 Site B 1800 2000 1000 No discharge The river is divided into numbered blocks. For example, block ‘2003-198’ will th Upper Middle Lower pass Singleton on the 198 day of 2003 sector sector sector (17 July). In this example, suppose block 198 could hold 112 tonnes of salt. 4 Credits determine who Credits can be traded can discharge salt There are a total of 1000 salt Licence holders’ need to discharge credits in the scheme— discharge depends on highly different licence holders have variable operational conditions at different numbers of credits (see each site. Credit trading gives page 10 for a list of credit holders each licence holder the flexibility and the initial credit allocation). to increase or decrease their Licence holders can only discharge allowable discharge from time to salt into a river block in proportion time while limiting the combined to the credits they hold—1 credit amount of salt discharged across allows a discharge of 0.1% of the the valley. total allowed. The trading system is online, So, suppose block 2003-198 could allowing licence holders to trade handle 112 tonnes of salt (the Total quickly and simply. The trades Allowable Discharge for this can be for one or many blocks block). Then, a licence holder with (i.e. a single day or longer 20 credits could discharge 2.24 periods), and the terms of the tonnes (112 x 20 x 0.1%), and a trade are negotiated by the parties licence holder with 45 credits involved. could discharge 5.04 tonnes A register ensures the information (112 x 45 x 0.1%), into that block. on credit holdings is publicly The licence holder performs a available at all times. Other second calculation to determine information on the trading scheme what volume of their discharge is also available. water contains the permitted tonnage of salt. Note: the River Register indicates when discharges can occur (see page 8). 199 201 202 Site A Site A Site A discharge 198 200 201 Singleton less than Singleton Singleton 197 199 200 900EC 196 198 199 195 e 197 198 arg ch is Site B Site B d Site B On 15 July, block 198 passes Site A. With On 16 July, block 198 passes Site B. With On 17 July, block 198 passes Singleton 20 credits, Site A could discharge 45 credits, Site B could discharge with salt concentration less than 900EC. 2.24 tonnes (112 x 20 x 0.1%). 5.04 tonnes (112 x 45 x 0.1%). If Site A did not discharge, it could trade 20 credits to Site B which could then discharge 65 credits of salt— 7.28 tonnes (112 x 65 x 0.1%). 5 What makes this scheme successful? The scheme has been Rigorous data and A community prepared to designed to suit the modelling work together and try unique characteristics new ideas of the Hunter River Having a good understanding of The scheme only came into being catchment. the river was the basis to because the parties involved were designing an effective scheme. prepared to work together to find A number of key factors Data has been collected over a solution. Mines, power stations many years and a model of the and farmers put years of conflict working together have river’s behaviour developed by the and mistrust behind them to find made this innovative former Department of Land and a way forward. The EPA played solution such a success. Water Conservation (DLWC). an important role in looking for alternative market-based The researchers found that when strategies rather than reapplying the flow in the river increased, traditional pollution control salinity increased for a few hours thinking. DLWC was instrumental and then dropped to very low in trialling and implementing the levels. Their explanation was that water management aspects of the it rose initially as the river picked scheme.