Pipes through the Bank Craig & Sharon Saunders (St George)

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1 Department of Employment, Economic Development and Innovation Pipes through the Bank Craig & Sharon Saunders (St George) Overview Craig and Sharon Saunders own and manage three irrigated cotton, dryland wheat and grazing properties in the St George area (part of the Balonne River catchment). The original property, Ford Park has been in the Saunders family for over 40 years, with Craig and Sharon taking over management of the property in the 1990 s. Four years ago Craig joined forces with Justin Schultz, WaterBiz to investigate alternatives to traditional siphon irrigation. As a result Craig and Justin designed and constructed a siphon less watering set up utilising pipes through the bank (PTB) with variable rates of flow. Each pipe waters 11 furrows or 12 metres and is designed to suit the 12 metre machinery in use. Saunders Farming also operates a centre pivot machine irrigating 89 hectares with a system capacity of 10.1 mm/day. This machine is located on Craig s marginal country, irrigating red hard setting soils. Motivator for change It was initially thought the main motivator for change four years ago was water savings. They have achieved a 25 % water saving. However, looking back, the team have realised that the real motivator was actually labour. Through working with WaterBiz and installing the PTB system the team have not only achieved this water saving, but have also had a labour saving of 50% and a yield increase of 20%. Justin has found that the main water savings are not a result of the pipes but actually by optimising the flow rate and the run times. In the 2010/11 season the traditionally lowest yielding farm actually out yielded the original farm for the first time. This improvement was associated with reduced water logging as they are now able to to get water on and off fields quickly. Owners: Location: Total area: Saunders Farming Pty Ltd Craig & Sharon Saunders St George hectares Cotton area: 647 hectares 2010/11 yield: bales/ha 2010/11 water: 7.2 ML/ha Field length: 500 m to 1700 metres The driver is yield not water savings One field is over 1700 metres long! Don t just mirror image your neighbour s farm Cotton being irrigated with Pipe through the Bank System Justin Schultz, Waterbiz and Craig Saunders, Saunders Farming Pty Ltd

2 The evolution of design Saunders Farming initially started working with Olive Hood over seven years ago, using the Irrimate tool which confirmed that the only real option for efficient watering was to run the system with high flow rates (due to run length and soil type). However, higher flow rates were associated with an increased number of siphons and the labour to start them. Therefore the team investigated options for retrofitting the existing irrigation infrastructure in a way that was easy to maintain, reduced labour requirements, allowed uniformity of application across the farm and increased water use efficiency. Four years ago, Craig approached Justin and said I m sick of changing siphons I don t want to change any more siphons so we ve got to come up with a better way to irrigate. Since then the farm has progressed from using 1.5 inch siphons on 1000m row lengths for 24 hour waterings, to 3 inch siphons on 1000m rows taking 12 hours, to the first pipe through the bank (PTB) system. In the PTB trial period, flexible fluming was installed inside the head ditch. Whilst working really well for 2 hours it then blocked up with short lengths of grass stopping the water flow completely. Undeterred, the team then trialled through the bank pipes made from recycled milk bottles (Green Pipe), set at 12 metre spacings and watering 11 furrows each. With this system, there is no pipe within the launch bay area, it is all below ground and there are vertical rises so weed management is not an issue. This system uses larger 250 mm internal diameter pipes with adjustable flaps to control water flow. The team attribute the ability to either adjust the flap, or adjust the head on the head ditch to achieve an optimum water output, as a key to the system s success. The variable system has meant cotton fields could be watered according to the crops specific requirements at the time, with rates adjusted during the watering based on extensive moisture probe data (flumes, Irrimate TM, C-Probes and the new SISCO - Surface Irrigation Simulation Calibration and Optimisation - tool). The season will see the entire cotton irrigation area being watered with the PTB pipes and one centre pivot machine. Figure 1 Cross-section view of PTB irrigation system 2

3 The role of SISCO In the season Justin used SISCO, the new irrigation optimisation program developed by University of Southern Queensland (USQ) and National Centre for Engineering in Agriculture (NCEA). SISCO is the improved version of the SIRMOD (Surface IRrrigation simulation, evaluation and Design) software, that allows you to optimise for more then one parameter at once cutting down trial times. On the Saunders irrigation area the system is designed for 8 hour irrigation events to optimise labour, meaning the system is optimised for a range of flow rates. For more information about this new tool, SISCO, contact NCEA on telephone: (07) or ncea@usq.edu.au. Uniformity down the rows Saunders Farming and WaterBiz have overcome uniformity issues experienced in similar PTB set ups by narrowing the spacings between the pipes to 12 metres. The diameter of the pipes is smaller then trialled in other areas, allowing greater control of the amount of flow that comes out of that pipe. There is a trough in front of the rows in the launch bay area, hence the water runs out of the pipes down to the depression and then the water level rises and evenly runs up the furrows. The other important factor affecting uniformity down the rows, is the high flow rates that they are using. These flows are much higher than those used by most other irrigation properties. Justin Shultz believes that because of the amount of water we re pushing down the rows, we have to get uniformity, there s just no other way for it to happen. Wheel tracks are still an issue. However, the team have designed the system to accommodate the 12m gear used on the farm. The pipe outlets are located in the guess row as far away from the wheel tracks as possible. The water has to move sideways in the launch bay area first in order to go down the wheel tracks. A system evaluation, conducted by Justin Schultz, has found: Uniformity of 90 % or better (the eveness of he amount water infiltration along the furrow length) Application efficiency of 85 % or better (the total water infiltrated as percentage of total water applied) Requirement efficiencies of 100% (the percentage of deficit filled at an irrigation) Run time eight hours Figure 2 Aerial view of PTB irrigation demonstrating pipe outlet situated in Guess row away from wheel tracks 3

4 Benefits Saunders Farming have found a number of benefits of using the PTB irrigation system, including: - Water savings - Labour savings - Increased yields due to less water logging and better water management - Easily adaptable to existing siphon systems - Optimising irrigation to 8 hour shifts - Simpler irrigation Water savings: 25% Yield increase: 20% Labour savings: 50% Water bubbling out of pipe outlet during irrigation Pipe outlet after irrigation Cost Criag Saunders has found the cost of retrofitting pipes through the bank on a traditional siphon furrow field is about $500/hectare. This cost includes both the cost of the pipe and the earthworks required. They have found a cost effective source of pipe in The Green Pipe company. Each length of pipe costs approximately $450 with the adjustable valve attached. Saunders Farming fabricates their own handles which they then attach to each of the adjustable valves. Valve mechanism on pipe with handle Saunders Farming believe that maintenance is somewhat similar to that of a conventional siphon system. While there is no rotobucking and less repairs with shovels, the PTB system does require the trough area to be graded to drop it about 100 mm. They have found there is less maintenance required on the head ditch each year as they can be built bigger than normal - their size is not restricted by siphons. At this stage, the Saunders Farming team have not had any maintenance issues in relation to the adjustable valves and pipes as they have only been installed a short time. They envisage though that maintenance will be required for the valves and mechanism that seal the pipe down the track, which could be done between seasons. Where to now? Saunders Farming are heading towards total automation of their system with the help of in row sensors. When water hits these sensors it sends a signal to the head ditch which opens and shuts the appropriate gates. Although still a few years away, it is progression towards watering without leaving your office. We ve gone and identified whatever the design constraints are and then we built a system around that and I think if you were to follow that procedure, you would end up with a great result as well. It is imperative to consider using a water specialist, who can assist you identify your system constraints and design a system that suits your needs. 4

5 Acknowledgement The More Profit Per Drop team would like to acknowledge all of the information provided by Craig Saunders, Saunders Farming Pty Ltd and Justin Schultz, WaterBiz in the development of this case study. Contact Us More Profit Per Drop team members: Graham Harris, Toowoomba - (07) Bec Raymond, Goondiwindi - (07) Jenelle Hare, Dalby - (07) Nikki Pilcher & Gina Mace, St George - (07) Mary Philp, Toowoomba - (07) Simon Vriesema, Toowoomba - (07) About us The DEEDI More Profit Per Drop team is contracted to deliver the extension component of the Healthy HeadWaters Water Use Efficiency (HHWUE) project. The HHWUE project is managed by DERM and is funded by the Australian Government as part of the Sustainable Rural Water Use and Infrastructure Program under the Water for the Future initiative. The HHWUE Project is helping Queensland Murray Darling Basin irrigators invest in more efficient irrigation systems and technologies that reduce water loss, delivering long-term economic benefits. It is also returning a share of water savings to the basin s rivers, wetlands and floodplains. In addition to funding for on-farm irrigation efficiency improvements, irrigators may also access other services under the HHWUE project including information about water efficient technologies, analysis of existing practices on farms and options for improving water efficiency. Disclaimer This product has been prepared by the State of Queensland as an information-only source. The State of Queensland makes no statements, representations, or warranties about the accuracy or completeness of, and you should not rely on, any information contained in this product. Any reference to any specific organisation, product or service does not constitute or imply its endorsement or recommendation by the State of Queensland. The Queensland Government disclaims all responsibility and all liability (including, without limitation, liability in negligence) for all expenses, losses, damages and costs you might incur as a result of the information being inaccurate or incomplete in any way, and for any reason. The State of Queensland, Department of Employment, Economic Development and Innovation Copyright protects this material, inquiries should be addressed to copyright@deedi.qld.gov.au (telephone ) Pipe through the bank with valve mechanism Irrigating with PTB system, St George 5