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| − | {{SPIS Safeguard Water}}{{Back to SPIS Toolbox}} | + | {{SPIS Safeguard Water}}{{Back to SPIS Toolbox}}<br/> |
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| − | === '''<span style="color:#879637;">Analyze Water Extraction</span>''' === | + | === '''<span style="color: rgb(135, 150, 55);">Analyze Water Extraction</span>''' === |
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| | Water extraction must be based on a corresponding water withdrawal license that also provides for information on the allowed annual or monthly quantities/quotas and on specific conditions or restrictions such as seasonal limits. This step deals with the collection of information on the existing or planned water extraction approach (gravity, manual-lifting or motor-pump) and the water pump. Furthermore, the actual water availability must be evaluated. Both aspects are essential in determining whether an existing or planned irrigation system can be operated in a sustainable way. | | Water extraction must be based on a corresponding water withdrawal license that also provides for information on the allowed annual or monthly quantities/quotas and on specific conditions or restrictions such as seasonal limits. This step deals with the collection of information on the existing or planned water extraction approach (gravity, manual-lifting or motor-pump) and the water pump. Furthermore, the actual water availability must be evaluated. Both aspects are essential in determining whether an existing or planned irrigation system can be operated in a sustainable way. |
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| − | The '''[[:File:SAFEGUARD_WATER_–_SPIS_Water_Resource_Management_Checklist.xlsx|SAFEGUARD WATER – Water Resource Management Checklist tool]]''' tool of this manual provides for an orientation for the information and data to be collected and reviewed in Section 2. The analysis of water extraction potential from a well requires technical information that generally is provided by technical service providers (drilling contractor, pump manufacturers, irrigation system contractors and pump installers). | + | The '''[[:File:SAFEGUARD WATER – SPIS Water Resource Management Checklist.xlsx|SAFEGUARD WATER – Water Resource Management Checklist tool]]''' of this toolbox provides for an orientation for the information and data to be collected and reviewed in Section 2. The analysis of water extraction potential from a well requires technical information that generally is provided by technical service providers (drilling contractor, pump manufacturers, irrigation system contractors and pump installers). |
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| | The main aspect in this process is to evaluate the water availability in the selected water source. For surface water sources (pond/reservoir, lake and perennial river) a general assessment is undertaken as to whether the required water quantities can be provided in each month of the year. For wells and boreholes exploiting groundwater re-sources a test to estimate the hydraulic properties of the aquifer system is required in order to arrive at a sustainable abstraction rate. This is done by means of a pumping test (also called: aquifer test), which should be carried out after the installation of a pump. A pumping test is a field experiment in which a well is pumped at a controlled rate and water-level response (drawdown) is measured in one or more surrounding observation wells and optionally in the pumped well (control well) itself; response data from pumping tests are used to estimate the hydraulic properties of aquifers, evaluate well performance and identify aquifer boundaries. Typically, aquifer properties are estimated from a constant-rate pumping test by fitting mathematical models (type curves) to drawdown data through a procedure known as curve matching and taking into consideration the geological set-up of the aquifer. | | The main aspect in this process is to evaluate the water availability in the selected water source. For surface water sources (pond/reservoir, lake and perennial river) a general assessment is undertaken as to whether the required water quantities can be provided in each month of the year. For wells and boreholes exploiting groundwater re-sources a test to estimate the hydraulic properties of the aquifer system is required in order to arrive at a sustainable abstraction rate. This is done by means of a pumping test (also called: aquifer test), which should be carried out after the installation of a pump. A pumping test is a field experiment in which a well is pumped at a controlled rate and water-level response (drawdown) is measured in one or more surrounding observation wells and optionally in the pumped well (control well) itself; response data from pumping tests are used to estimate the hydraulic properties of aquifers, evaluate well performance and identify aquifer boundaries. Typically, aquifer properties are estimated from a constant-rate pumping test by fitting mathematical models (type curves) to drawdown data through a procedure known as curve matching and taking into consideration the geological set-up of the aquifer. |
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| | '''Recommendation''': Require your well contractor and pump installer to perform the analysis and provide the corresponding data before any further planning for the SPIS is undertaken. | | '''Recommendation''': Require your well contractor and pump installer to perform the analysis and provide the corresponding data before any further planning for the SPIS is undertaken. |
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| − | {| style="width:100%;" cellspacing="1" cellpadding="1" border="0" | + | {| style="width: 100%;" border="0" cellspacing="1" cellpadding="1" |
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| − | | style="background-color: rgb(225, 229, 205)" | | + | | style="background-color: rgb(225, 229, 205);" | |
| | '''Important''': If one or more of the above principles with regard to the different flow rates are not applicable in the data comparison, the system cannot be operated on a sustainable basis and its operation may result in severe negative ecological (dried out well, negative water balance in the aquifer, dropping water table) and financial impacts (over-dimensioning of system, insufficient water availability for agricultural production). A need to introduce adaptations to the system design or even abandon the project is thus apparent. | | '''Important''': If one or more of the above principles with regard to the different flow rates are not applicable in the data comparison, the system cannot be operated on a sustainable basis and its operation may result in severe negative ecological (dried out well, negative water balance in the aquifer, dropping water table) and financial impacts (over-dimensioning of system, insufficient water availability for agricultural production). A need to introduce adaptations to the system design or even abandon the project is thus apparent. |
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| | |} | | |} |
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| − | === '''<span style="color:#879637;">Outcome/Product</span>''' === | + | === '''<span style="color: rgb(135, 150, 55);">Outcome/Product</span>''' === |
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| | *Compilation of data and information on flow rates for water source, pump and system; | | *Compilation of data and information on flow rates for water source, pump and system; |
| | *Comparison of flow rates for safe yield of water source, water withdrawal license, pump and irrigation system. | | *Comparison of flow rates for safe yield of water source, water withdrawal license, pump and irrigation system. |
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| − | === '''<span style="color:#879637;">Data Requirements</span>''' === | + | === '''<span style="color: rgb(135, 150, 55);">Data Requirements</span>''' === |
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| | *Water source flow rate; | | *Water source flow rate; |
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| | *Expected water demand of the irrigation system. | | *Expected water demand of the irrigation system. |
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| − | === '''<span style="color:#879637;">Important Issues</span>''' === | + | === '''<span style="color: rgb(135, 150, 55);">Important Issues</span>''' === |
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| | *Safe yield (sustainable withdrawal) of the water source is the determining factor for a sustainable operation; | | *Safe yield (sustainable withdrawal) of the water source is the determining factor for a sustainable operation; |
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| | *Information on existing water sources and pumping installation is available with technical service providers. | | *Information on existing water sources and pumping installation is available with technical service providers. |
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| − | === '''<span style="color:#879637;">People/Stakeholders</span>''' === | + | === '''<span style="color: rgb(135, 150, 55);">People/Stakeholders</span>''' === |
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| | *Farmer and Agricultural Advisor; | | *Farmer and Agricultural Advisor; |
Water extraction must be based on a corresponding water withdrawal license that also provides for information on the allowed annual or monthly quantities/quotas and on specific conditions or restrictions such as seasonal limits. This step deals with the collection of information on the existing or planned water extraction approach (gravity, manual-lifting or motor-pump) and the water pump. Furthermore, the actual water availability must be evaluated. Both aspects are essential in determining whether an existing or planned irrigation system can be operated in a sustainable way.
The main aspect in this process is to evaluate the water availability in the selected water source. For surface water sources (pond/reservoir, lake and perennial river) a general assessment is undertaken as to whether the required water quantities can be provided in each month of the year. For wells and boreholes exploiting groundwater re-sources a test to estimate the hydraulic properties of the aquifer system is required in order to arrive at a sustainable abstraction rate. This is done by means of a pumping test (also called: aquifer test), which should be carried out after the installation of a pump. A pumping test is a field experiment in which a well is pumped at a controlled rate and water-level response (drawdown) is measured in one or more surrounding observation wells and optionally in the pumped well (control well) itself; response data from pumping tests are used to estimate the hydraulic properties of aquifers, evaluate well performance and identify aquifer boundaries. Typically, aquifer properties are estimated from a constant-rate pumping test by fitting mathematical models (type curves) to drawdown data through a procedure known as curve matching and taking into consideration the geological set-up of the aquifer.
Based on the data obtained,key values related to the water abstraction (indicated as flow rates in m3/hour or m3/day) can be compared:
