The Biology And Physiology Of Macroinvertebrates Associated With A Public Water Supply

The work described is the result of research Carried out on some aspects of the biology of the ,Macroinvertebrates (principally crustaceans, insects and water mites) which have caused infestation problems in a water distribution system. A survey of the literature was carried out to determine the occurrence of macroinvertebrates in the water mains and the treatment methods used by other authorities with similar problems. The laboratory culture of the organisms, and the determination of the larval instars of Paratanytarsus sp. nov. (Diptera: Chironomidae) is described. Surveys of the macroinvertebrates at the treatment works and in the water distribution system were carried out over one and two year periods respectively, to determine the efficiency of the treatment, the extent of the infestations and the annual variations within the populations. Experiments were carried out to determine the effects of flow, food, chlorine and two pesticides, pyrethrins and Abate, on selected members of the mains fauna. Experiments were also carried out using a model rapid sand filter to determine the extent of penetration of the micro-organisms used as food. A discussion of the results and reasons for the success of certain organisms is given.