This page provides guidance for completing format MF4-F75 “Construction_supervision” regarding Spring supervision.
| PROCEED n° MF4-F27 | 1.0 | Spring supervision checklist | September 2026 |
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| V1 | Cutting walls & box foundation MF-M24 §2 and 3 |
|---|---|
| 1.1 | The spring measurements formats are filled and available MF4-F21, MF4-F22, MF4-F23 and is still up to date |
| 1.2 | Excavation dimensions are 20cm wide and 50cm deep mini, box excavation is 2.3m diameter |
| 1.3 | Soil is well compacted inside the excavations |
| 1.4 | Rebar mesh 20x20cm 8mm diameter is installed for the cutting wall |
| V2 | Box slab preparation MF-M24 §4 and 5 |
|---|---|
| 2.1 | Clean 4-5cm high lean concrete (1:3:6) is casted on masonry work |
| 2.2 | Lean concrete is 25-30cm under natural ground upstream |
| 2.3 | The PVC assembly for overflow, inlet and outlet pipes size match the design or standard and is pre-installed |
| 2.4 | Slab rebar mesh is supported by 2-3cm gravel above lean and conform to dimensions (60cm high, 162cm diam…) |
| 2.5 | Concrete preparation, tools and conditions are as methdology MF4-M13 §1 |
| 2.6 | Water agent knows he has to water the slab 2 times a day for 7 days |
| V3 | Spring box masonry validation MF-M24 §6 |
|---|---|
| 3.1 | Inside mold is installed and centered |
| 3.2 | The banana trunk are touching the mold, going above flat stones and filling the space between |
| 3.3 | The flat stones are well installed to give the maximum water channel possible |
| 3.4 | Gap between masonry and mold is at least 10cm all around |
| 3.5 | No water trapped visible upstream of cutting wall |
| 3.6 | Concrete preparation, tools and conditions are as methdology MF4-M13 §1 |
| V4 | Wall casting day MF-M24 §7 |
|---|---|
| 4.1 | Wall casting starting before 9am, the entire wall must be cast in one day in presence of the supervisor |
| 4.2 | Rebar mesh is as per methodology |
| 4.3 | False banana trunk are well installed for steps (40cm from left to right every 30cm) |
| 4.4 | Concrete preparation, tools and conditions are as methdology MF4-M13 §1 |
| 4.5 | Concrete is laid from one end, then progressively all around the mould |
| 4.6 | 15 minutes maximum between 2 concrete batches |
| 4.7 | Uninterrupted vibration is done with a steel GI pipe inside and woodden hammer on both sides of reservoir |
| 4.8 | If a 2nd or a 3rd ring is necessary, check installation of mould (centering, level, oil, bolts&nuts, cleanliness) |
| 4.9 | Call the Water agent the day after casting to ensure the spring box has been watered and covered |
| 4.10 | Water agent knows he has to water the spring box 2 times a day for 7 days |
| V5 | Cover slab preparation MF-M24 §8 |
|---|---|
| 5.1 | Catchment area filling is as per methodology (gravels-stones-gravels) |
| 5.2 | The level of the filling is up to cutting walls level |
| 5.3 | Rebar mesh (20x20cm 8mm) is covering whole area 2-3cm above filling and linked with wire to cutting wall bended rebar |
| 5.4 | Concrete preparation, tools and conditions are as methdology MF4-M13 §1 |
| 5.5 | Water agent knows he has to water the slab 2 times a day for 7 days |