| Researcher(s) |
Sophie Willsher |
|---|---|
| Contact email | sophiew@southcoastnrm.com.au |
| Contact phone | 08 9845 8537 |
| Year(s) | 2021 - 2023 |
| Contributor | South Coast Natural Resource Management Inc. |
| Trial location(s) |
Dalyup, WA
Neridup, WA |
| Further information | View external link |
Understanding return on investment of sub-surface water management options for waterlogged areas in the Western Region.
This investment aims to assist growers in making informed decisions around construction of drainage to reduce the impacts of waterlogging on crop production and farm profitability. This will be achieved through grower participation in the planning, development, monitoring and maintenance of the drainage installation trial sites. Data (cost of implementation/ maintenance, water movement, establishment, biomass, yield etc.) from within the zone of influence of the drainage and outside this zone at each site will be collected
over time to give growers a better understanding of the improvements in yield and time to return on investment at each site.
Waterlogging is a serious threatening process for growers across WA, with real implications to crop health and farm profitability. The Subsurface Drainage Return on Investment trial aimed to assist growers in making informed decisions around the efficacy of subsurface drainage in reducing impacts of waterlogging on crop production systems and increasing farm profitability through yields.
Two subsurface drainage demonstration sites were established in the high rainfall zones of Neridup, and Dalyup in the Esperance Port Zone. Monitoring began in 2021 and collected data on perched water levels, yield improvements and environmental factors. The 2021 and 2022 harvests were record breaking for the area, as a result of high rainfalls, and although Neridup and Dalyup both experienced significant waterlogging, the drains performed well and produced substantial yield benefits. The drains also presented yield benefits in 2023 despite it being a decile 1 – 3 year for the trial.
The time until return on investment for subsurface drainage is determined to be between 9 – 12 years and is expected to provide internal rates of return to growers between 12 – 16%. This project finds subsurface drainage to be a profitable and effective management tool to address waterlogging. Further research and expertise is required to support broadscale adoption.
| Lead research organisation |
South Coast Natural Resource Management Inc. |
|---|---|
| Host research organisation | N/A |
| Trial funding source | GRDC SCN2005-001SAX |
| Related program | N/A |
| Acknowledgments | N/A |
| Other trial partners | Not specified |
| Crop types | Oilseed: Canola Cereal (Grain): Wheat Cereal (Grain): Barley |
|---|---|
| Treatment type(s) |
|
| Trial type | Demonstration |
| Trial design | Not applicable |
| Sow date | Unknown |
|---|---|
| Harvest date | Unknown |
| Plot size | Not specified |
| Plot replication | Not specified |
| Other trial notes |
Background to the Trial Subsurface drainage is a surface water management tool that addresses perched water in the subsoil of the paddock. Unlike open drainage systems, tile drains, or slotted polypipe, are buried to the depth of the clay layer, typically around 600mm – 800mm deep. Due to the depth that these pipes are buried, growers are able to crop overtop of the drains, increasing your arable area. Water entering into the topsoil is trapped by an impenetrable clay layer, which creates waterlogged conditions, and leads to reduced productivity, or crop drownings. The thin slits along the polypipe allow perched water to infiltrate into the pipe and therefore drain away from the root zone of the crop. This drainage action in turn alleviates waterlogging and increases productivity. The design of subsurface drainage systems is largely variable but can prove to be a valuable resource if growers choose to discharge the water into farm dams. Water exiting the root zone and draining into dams may increase water available for stock or spray, an added benefit of these systems that is being explored by South Coast NRM and others across the South Coast. |
| Sow date | Unknown |
|---|---|
| Harvest date | Unknown |
| Plot size | Not specified |
| Plot replication | Not specified |
| Other trial notes |
Background to the Trial Subsurface drainage is a surface water management tool that addresses perched water in the subsoil of the paddock. Unlike open drainage systems, tile drains, or slotted polypipe, are buried to the depth of the clay layer, typically around 600mm – 800mm deep. Due to the depth that these pipes are buried, growers are able to crop overtop of the drains, increasing your arable area. Water entering into the topsoil is trapped by an impenetrable clay layer, which creates waterlogged conditions, and leads to reduced productivity, or crop drownings. The thin slits along the polypipe allow perched water to infiltrate into the pipe and therefore drain away from the root zone of the crop. This drainage action in turn alleviates waterlogging and increases productivity. The design of subsurface drainage systems is largely variable but can prove to be a valuable resource if growers choose to discharge the water into farm dams. Water exiting the root zone and draining into dams may increase water available for stock or spray, an added benefit of these systems that is being explored by South Coast NRM and others across the South Coast. |
| Sow date | 11 March 2024 |
|---|---|
| Harvest date | Unknown |
| Plot size | Not specified |
| Plot replication | Not specified |
| Other trial notes |
Background to the Trial Subsurface drainage is a surface water management tool that addresses perched water in the subsoil of the paddock. Unlike open drainage systems, tile drains, or slotted polypipe, are buried to the depth of the clay layer, typically around 600mm – 800mm deep. Due to the depth that these pipes are buried, growers are able to crop overtop of the drains, increasing your arable area. Water entering into the topsoil is trapped by an impenetrable clay layer, which creates waterlogged conditions, and leads to reduced productivity, or crop drownings. The thin slits along the polypipe allow perched water to infiltrate into the pipe and therefore drain away from the root zone of the crop. This drainage action in turn alleviates waterlogging and increases productivity. The design of subsurface drainage systems is largely variable but can prove to be a valuable resource if growers choose to discharge the water into farm dams. Water exiting the root zone and draining into dams may increase water available for stock or spray, an added benefit of these systems that is being explored by South Coast NRM and others across the South Coast. |
| Sow date | Unknown |
|---|---|
| Harvest date | Unknown |
| Plot size | Not specified |
| Plot replication | Not specified |
| Other trial notes |
Background to the Trial Subsurface drainage is a surface water management tool that addresses perched water in the subsoil of the paddock. Unlike open drainage systems, tile drains, or slotted polypipe, are buried to the depth of the clay layer, typically around 600mm – 800mm deep. Due to the depth that these pipes are buried, growers are able to crop overtop of the drains, increasing your arable area. Water entering into the topsoil is trapped by an impenetrable clay layer, which creates waterlogged conditions, and leads to reduced productivity, or crop drownings. The thin slits along the polypipe allow perched water to infiltrate into the pipe and therefore drain away from the root zone of the crop. This drainage action in turn alleviates waterlogging and increases productivity. The design of subsurface drainage systems is largely variable but can prove to be a valuable resource if growers choose to discharge the water into farm dams. Water exiting the root zone and draining into dams may increase water available for stock or spray, an added benefit of these systems that is being explored by South Coast NRM and others across the South Coast. |
| Sow date | Unknown |
|---|---|
| Harvest date | Unknown |
| Plot size | Not specified |
| Plot replication | Not specified |
| Other trial notes |
Background to the Trial Subsurface drainage is a surface water management tool that addresses perched water in the subsoil of the paddock. Unlike open drainage systems, tile drains, or slotted polypipe, are buried to the depth of the clay layer, typically around 600mm – 800mm deep. Due to the depth that these pipes are buried, growers are able to crop overtop of the drains, increasing your arable area. Water entering into the topsoil is trapped by an impenetrable clay layer, which creates waterlogged conditions, and leads to reduced productivity, or crop drownings. The thin slits along the polypipe allow perched water to infiltrate into the pipe and therefore drain away from the root zone of the crop. This drainage action in turn alleviates waterlogging and increases productivity. The design of subsurface drainage systems is largely variable but can prove to be a valuable resource if growers choose to discharge the water into farm dams. Water exiting the root zone and draining into dams may increase water available for stock or spray, an added benefit of these systems that is being explored by South Coast NRM and others across the South Coast. |
SILO weather estimates sourced from https://www.longpaddock.qld.gov.au/silo/
Jeffrey, S.J., Carter, J.O., Moodie, K.B. and Beswick, A.R. (2001). Using spatial interpolation to
construct a comprehensive archive of Australian climate data , Environmental Modelling and Software, Vol
16/4, pp 309-330. DOI: 10.1016/S1364-8152(01)00008-1.
