Stormwater harvesting from Roseworthy Industrial Estate
Stormwater from development in Roseworthy Industrial Estate is captured in a 35 ML storage basin built in 2008 on Flett Road where most of it evaporates. To remain effective, the basin level has to be lowered by pumping to a drain further south, but that causes nuisance, so Bunyip Water is constructing a high-pressure pump station and 1km rising main to connect to the existing main at Thiele Highway. The pump will operate automatically to fill Eden Tank, and modifications will be made to the existing valves and controls to manage the additional flow, including when Hill Dam is already full. The amount of water is variable, and so is the quality, but the contents will be utilised for irrigation in Hewett and the western Barossa Valley in the coming summer.
Hewett Reserves are looking good
Irrigation at four reserves in Hewett were converted from drinking water to recycled water, as part of the funding commitment made to the Australian Government to harvest stormwater and reduce River Murray water use. Researchers have proven that irrigated reserves deliver strong benefits to community health by providing cool refuges, contact with nature, and exercise. Access to drinking water is often limited, but the Bunyip Water scheme provides higher flows and pressures so irrigation be achieved efficiently and quickly, at affordable prices. The reserves are looking good - it's great for the local community and the State. A 1.9km network of 'purple pipes' was constructed and pressure tested by SADB in record time in August 2016, and it includes provision for expansion to serve two schools and the neighbouring Town of Gawler.
Managed Aquifer Recharge trial complete
Managed Aquifer Recharge (MAR) is Bunyip Water's strategy for balancing flows available in winter with demand in summer. Water will be temporarily stored in an existing underground aquifer which is a thick layer of water-bearing sandy material extending from about 40m to 90m below ground.
Roseworthy Township Expansion approved (more water eventually)
The Development Plan Amendment (DPA) to include the Roseworthy Township Expansion (RTE) was approved by the Minister of Planning today.
Hill Dam is full for the first time
Once the main pumps were commissioned, we continued pumping to transfer the water from Wingate Basin to Hill Dam. After such a dry year last year and the stress of Early Water, it is very satisfying to see the dam brim full ready for the coming irrigation season. HydroPlan will operate the scheme for 12-18 months before handing over to the foundation customer's long-term operators.
The Gawler River floods and Wingate Basin fills to the brim
The Gawler River doesn't break out of its banks very often, but when it does it damages many homes and businesses. It flooded over its banks early this morning, and water cascaded into Wingate Basin. The basin was already full because we have been harvesting from the river since first commissioning pump station 1 on 7/07/2016. Full is normally about 1m from the rim, but the floods have filled it higher again - which is no surprise given the basin is a hole in the flood plain. Some very minor damage occured to the fence and terrestial plantings, but the new infrastructure held up very well and performed exactly as predicted.
Final milestone - commissioned on time, under budget
The final funding milestone was reached today - on time and under budget, completing 6 months of design/approvals and 12 months of construction. It's been a huge effort by a large number of firms and people involved - and credit must go to HydroPlan's engineering design and construction management of over 100 separate contracts. It's remarkable that the walls of pump station 3 and 4 were still being assembled 3 weeks ago, and that three pump stations (2,3,4) had to be commissioned together as they are dependent on each other.
Pump stations 3 and 4 are almost ready
With only 3 weeks to the final milestone, things are happening quickly as we race to meet the commissioning deadline. The walls went up on Pump Station 3 and 4 today, and whilst McMahon's were doing that, they swung in the 1.6 tonne pumps for Pump Technology Services. There are 10 contracts to coordinate before we can confirm the design flows are achieved when we push water 200m uphill through 28km of pipes to Hill Dam. Coordinating power authorities and retailers is very difficult, but the other contractors involved are working around them. Dematec are doing a fantastic job by preassembling and testing the electrical controls so they can minimise the time required for finishing off on site.
Hill Dam is complete - despite wet weather
This winter has been extraordinarily wet, and that made lining of Hill Dam almost impossible to complete. The lining subcontractor has been a major disappointment, causing costs for everyone far beyond what was possible. An innovation and a lot of money pulled this part of the project back from the brink. A plastic mesh was placed over the wet clay so foot-traffic didn't leave ridges that would impact the 1.5mm thick HDPE white plastic liner. The integrity of the liner has since been verified by the leak detection system. The liner covers 100,000 square metres and the industry standard defines 20 holes of 2mm diameter as acceptable. A great specialist called Geotest subsequently found only two holes smaller than that and fixed them. Finding a needle in a haystack would be much easier!
Wingate Basin is complete
McMahon Services have done a great job in completing this technically difficult project on time and within budget. The compacted clay liner has been covered with topsoil ready for planting. The embankments have a sprinkler system to assist establishment of grasses and native plantings, and the flat bottom of the basin will maintain wetland plants to protect the clay and maintain habitat. Two submersible pumps will be able to lift 52 ML/d (600 L/s) into the basin to fill it in 8 days when a flood allows harvesting to commence.
Funding milestone reached
Representatives from the Australian Government inspected the works today to confirm Milestone 10 funding under the Natonal Urban Water and Desalinaton Plan, and terms of the final Milestone in August. As progress is on track, Light Regional Council has been able to secure the full $10.7m funding for the project.
Eden Tank is complete - ready for the next fire
Eden Tank sits on the crest of the hill between Roseworthy and Shea Oak Log. It has multiple functions in transfering water and controlling multiple pumps that utilise the mainline. But although it was not in the Project Plan, it was readily given another function - of providing fire water. The tank is at the downwind edge of where the Pinery bushfires burned 86,000 hectares on 25/11/2015 next to an old tree which bears the scars of a much earlier fire. Most of our pipes had been buried at that stage, but some uninstalled pipes were burned in the fire's destructive path.
Remodelling of Wingate Basin is underway
Wingate Basin is being remodelled by McMahon Services from a 'borrow pit' into a 430 ML water storage dam. Wingate Basin is the hole left in the flood plain when the Northern Expressway needed soil to cross above the Gawler River. Light Regional Council saw the opportunity to create a stormwater harvesting facility, spawning the idea for the Gawler Water Reuse Scheme. HydroPlan's design takes the idea further by remodelling the basin into a dam so water can be pumped in quickly when floods allow harvesting to commence. A neighbour agreed to swap clay for sandier material in their paddock, and McMahon's skilled engineers created a large cutting for the large pumping manifold. The contract was awarded 27/01/2016 and it includes civil works for a large pumping chamber on the southern tip to harvest water.
Construction of Hill Dam is underway
Work is well-underway at Hill Dam. Exact Contracting were awarded the contract 23/02/2016 and within a week had a procession of floats to bring the 190 tonne excavator and 777 dump trucks to site for assembly. They are wasting no time moving over a hundred thousands tonnes of soil to build a dam on the crest of the hill on Gomersal Road, in the middle of a vineyard which hasn't been completed due to lack of water. Adelaide oval can fit comfortably inside this huge dam which will hold 680 ML and supply water for miles around using gravity.
Early Water busts the drought
The very dry conditions in this 2015-16 season have created severe water shortages for vineyards in the Barossa. But Wingate Basin needed to be drained for construction, and construction water was needed at Hill Dam - so the crazy idea of "Early Water" was born. Permission from the Principal was given to the foundation customer to temporary use the incomplete pipeline, provided that there was no impact to the cost, time or quality of the core project. At the foundation customer's cost, three diesel pumps in series were set up to lift water 200m over 28 km. A young team of 12 has kept them running day and night for 3.5 months until today, delivering 410 ML of desperately needed water. The efforts of all involved, and the generosity of neighbours and stakeholders has been legendary.
Installation of main pipeline completed
Leed commenced construction of the primary pipelines (39kms) on 28th September 2015 and completed the work by 18th December 2015. Leed’s innovative construction methodology allowed them to achieve an average installation rate of 3.75 km per week. By agreement with the Principal, the trunk main was used by others for 'Early Water' and Practical Completion was deferred until 16/02/2016 when all pipelines could be pressure tested.
Two Rivers Crossed In One Day
The importance of resources and management was highlighted today when Leed was crossing two rivers at once. The specialist crews involved in constructing and welding the polyethylene pipes were on hand to cross under the Gawler River at Hillier and the North Para River at Rosedale. Native vegetation has been identified and presevered, and the pipes will be secured against flood risks.
Stakeholders Witness Pipelaying Work
Under strict management by Leed's team, a large group of stakeholders, regulators and interested parties were allowed on site today to witness the installation process. The road closures organised with Council enables quick and safe movement of machinery and crews. Professional pipelayers have multiple teams to ensure the work goes smoothly. Advance crews expose services and prepare the ground for the trenching crew. Traffic management crews keep the site and public safe. Trenching is followed by the pipelayers, then the backfilling team, and finally a team to tidy-up and prepare for opening the road again.
Contract Awarded for Pipeline Contract
Following a tender and evaluation process, a contract for the construction of the main pipeline was awarded to Leed Engineering & Construction Pty Ltd on 28th August 2015. Leed are a South Australian owned company and Bunyip Water looks forward to working with them on this exiting project.
Five pipe-laying specialists have been invited to bid on the work to construct the pipeline. A requirement of funding is that contractors who are awarded contracts over $3m are accredited by the Federal Safety Commissioner.
Wherever the pipeline crosses a waterway a Permit for a Water Affecting Activity is required. Officers from DEWNR have inspected waterway crossings including this one at Greenock Creek. The suspended poly pipe in the foreground is not the GWRS. The GWRS will be much larger and buried!
Native Vegetation Assessment
Experts surveyed the native vegetation along the route to determine where the biodiversity risks are and how to manage them. A procedure has been developed from previous HydroPlan projects for reducing impact on native grasses where pipelines were laid on road reserves.
The Federal Minister for Agriculture, The Hon. Barnaby Joyce MP visited the Barossa Valley on Thursday, April 16 and was accompanied by Senator Sean Edwards, Senator for South Australia.
Two dams are proposed for storing the water after it is captured in winter. Geotechnical investigations have been conducted by FMG Engineering to determine the presence of clay and rock primarily.
Green Light for Scheme
On the 31st March 2015 Light Regional Council resolved to proceed with the project. For details refer to the media statement issued by Council on 8th April 2015. Articles subsequently appeared in a number of newspapers including The Bunyip, The Leader, The Barossa Herald, The Advertiser, The Stock Journal and the Barossa Valley Leader.