Peilstok/peilhengel
Met deze handmatige techniek kan de diepte van de waterbodem worden gemeten. De peilstok heeft een voet. Deze wordt verticaal naar beneden gelaten tot op de waterbodem. Vervolgens wordt de hoogte van de waterkolom boven de voet gemeten.
Een peilhengel is een peilstok aan een hengel. Het verschil tussen een stok en een hengel ligt in de benadering van de waterbodem via de kant (hengel) of vanuit een boot (stok). Indien de voet wordt uitgewisseld voor een punt kan ook de dikte van het ‘slappe’ (niet-geconsolideerde) sediment of sliblaag worden bepaald.
| General information | |||
| Name | Dipstick / sounding rod | ||
| Unit of measure and parameter | Height of water column in centimeters or thickness of the sludge layer | ||
| Nature technique | Physical | ||
| Place of application | in situ | ||
| Detection Mode | Drilling / stabbing or measurement at ground level/water bottom | ||
| Applicable in separate layers | new | ||
| Land soil/water bottom | water bottom | ||
| Step in the data collection chain |
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| Moment of availability results | Measurement results are available in the field | ||
| Technology development phase | Applied routinely | ||
| Method of purchasing | as service or as a device | ||
| General description of the implementation method | The dipstick with foot is sunk down to the sludge. There is a light version that is placed with a fishing rod or a heavier version that is carefully placed from a boat or into the water. The height of the water column can then be read on the basis of a measurement on the stick. This means that the depth at which the water bed is located is known on site. With a sounding rod the same can be done from the side up to a maximum waterway width of 6 m. If foot is exchanged for a point, the thickness of sediment or silt layers can also be determined. | ||
| Working principle | The height of the water column can be measured by means of a graduation on the stick. A fishing rod provides a good vertical measurement from the shore. | ||
| Point / line measurement / volume measurement | Point measurement | ||
Technical specifications (including accuracy) | Dipstick is made of aluminum; periodic calibration prevents measurement errors. Accuracy: ± 1 to 2 centimeters (depending on the wave action) | ||
| Typical depth range | Dipstick maximum 5 meters Leveling rod maximum 2 meters. | ||
| Time properties | A single measurement can be performed in a short time. | ||
| Measuring rate | From 1 minute per measurement | ||
| Presentation results | Observation is directly readable on the dipstick; several measurements form a cross section. | ||
| Cost | Vary very strongly per provider and conditions in the field: from € 20 to € 150 per measurement | ||
User information | |||
| availabilty | large number of providers | ||
| Is technology often used? | Very organized | ||
| Research phase in which technology can be applied |
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| Verification measurements / calibration measurements | are often used | ||
| Frequently used application in practice | Gauging in and out of smaller waterways and of sediment or sludge layer thickness | ||
| Suitability | Suitable for manually sounding waterways that are not too large. | ||
| Practical experiences in the Netherlands | It is used very regularly, mainly by water boards or consultancy firms throughout the Netherlands. Experience shows that the accuracy strongly depends on the circumstances and the sounder. Manual gauging usually gives a good idea of the thickness of the sludge layer. | ||
| “Dos“ | Measuring level with a higher measurement density at the slopes | ||
| “Don'ts” | Use as little pressure as possible when probing to press the foot into the sludge layer. | ||
References
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