Het Waterlaboratoirum is specialized in advanced sampling techniques. In addition to "normal" sampling by filling water bottles, we also perform more complex sampling. Examples are sampling of groundwater flows via monitoring wells, and sampling large volumes by using Grovols and Hemoflows.
With Grovol sampling, a complete filtration is carried out at the location site. Using a large-volume set-up consisting of a stainless steel set-up with a flow meter and a number of valves to regulate the set-up, approximately 50 to 100 liters of water is passed over a membrane filter. ‘Trapped’ bacteria from sampling are being cultured in the laboratory. With large volume sampling, the change on finding bacteria increases. This type of sampling is often used for a specific process to gain more knowledge into hygienic parameters.
Even more complex is Hemoflow sampling. Het Waterlaboratorium has developed a sampling method for investigating large volumes (50-3000 liters) of water over long periods for specific bacteria. At drinking water locations, even a few thousand liters can be sampled within 24 hours. The water is filtered through a so-called Hemofilter which is also used in the medical world, for example for dialysis. With this technique, microorganisms and/or viruses present are concentrated in the filter. The Hemoflow setup can be used for research on E. coli, Cryptosporidium, Giardia, Somatic and F-specific bacteriophages