What is eWQMS?

Emanti Management's Water Quality Management System (eWQMS) can be used to guide the tracking, reviewing and improving of water quality.

E.coli

Escherichia coli (E.coli) is used as an indicator of faecal pollution by warm blooded animals (often interpreted as human faecal pollution). The presence of faecal pollution by warm blooded animals may indicate the presence of pathogens responsible for infectious disease such as gastroenteritis, cholera, dysentery and typhoid fever after ingestion of contaminated water.

Effect and possible implications of failure

  • Health

The risks of being infected correlates with the level of contamination of the water and the amount of contaminated water consumed. Higher concentrations of E.coli in water will indicate a higher risk of contracting waterborne disease, even if small amounts of water are consumed. Any bacteriological failure with regards to E.coli can therefore be considered a direct indication of risk to health.

SANS 241 Standards

  • SANS 241 Table 1 (Microbioloigical safety requirements) column 3 Allowable Compliance Contribution (95% of samples min) Upper Limit: Not detected (count per 100 ml)
  • SANS 241 Table 1 (Microbioloigical safety requirements) column 4 Allowable Compliance Contribution (4% of samples max) Upper Limit: Not detected (count per 100 ml)
  • SANS 241 Table 1 (Microbioloigical safety requirements) column 5 Allowable Compliance Contribution (1% of samples max) Upper Limit: 1 (count per 100 ml)

Possible reason/s for failure

  • No disinfection (e.g. no chlorine dosing, no ozone dosing, no UV system)
  • No residual chlorine or low level of residual chlorine (e.g. chlorine not added at plant, residual chlorine below 0.2 mg/L at point of consumption)
  • Contamination (e.g. from pipe breaks and bursts, from repairs to network, infiltration or seepage from a contaminated source, sewage near groundwater sources, contamination from pit latrines/septic tanks, rubbish and faecal matter around standpipes)
  • Lack of maintenance (e.g. reservoirs and pipes not cleaned/flushed)
  • Poor design (e.g. long retention times in reservoir and distribution network, open reservoirs, large reticulation network with no additional chlorine dosing at reservoirs)
  • Sabotage/vandalism

Faecal Coliforms

Faecal coliform bacteria are found in water wherever the water is contaminated with faecal waste of human or animal origin. Faecal coliforms are primarily used to indicate the presence of bacterial pathogens such as Salmonella spp., Shigella spp., Vibrio cholerae, Campylobacter jejuni, Campylobacter coli, Yersinia enterocolitica and pathogenic E. coli. These organisms can be transmitted via the faecal/oral route by contaminated or poorly treated water and may cause diseases such as gastroenteritis, salmonellosis, dysentery, cholera and typhoid fever.

Effect and possible implications of failure

  • Health

The risks of being infected correlates with the level of contamination of the water and the amount of contaminated water consumed. Higher concentrations of faecal coliforms in water will indicate a higher risk of contracting waterborne disease, even if small amounts of water are consumed. Any bacteriological failure with regards to faecal coliforms can therefore be considered a direct indication of risk to health.

SANS 241 Standards

  • SANS 241 Table 1 (Microbioloigical safety requirements) column 3 Allowable Compliance Contribution (95% of samples min) Upper Limit: Not detected (count per 100 ml)
  • SANS 241 Table 1 (Microbioloigical safety requirements) column 4 Allowable Compliance Contribution (4% of samples max) Upper Limit: Upper Limit: 1 (count per 100 ml)
  • SANS 241 Table 1 (Microbioloigical safety requirements) column 5 Allowable Compliance Contribution (1% of samples max) Upper Limit: 10 (count per 100 ml)

Possible reason/s for failure

  • No disinfection (e.g. no chlorine dosing, no ozone dosing, no UV system)
  • No residual chlorine or low level of residual chlorine (e.g. chlorine not added at plant, residual chlorine below 0.2 mg/L at point of consumption)
  • Contamination (e.g. from pipe breaks and bursts, from repairs to network, infiltration or seepage from a contaminated source, sewage near groundwater sources, contamination from pit latrines/septic tanks, rubbish and faecal matter around standpipes)
  • Lack of maintenance (e.g. reservoirs and pipes not cleaned/flushed)
  • Poor design (e.g. long retention times in reservoir and distribution network, open reservoirs, large reticulation network with no additional chlorine dosing at reservoirs)
  • Sabotage/vandalism

Heterotrophic Plate Count

The Heterotrophic Plate Count detects a wide range of bacteria and is used to assess the general bacterial quality of water. Pollution can give rise to conditions conducive to bacterial growth leading to high heterotrophic plate counts.

Effect and possible implications of failure

  • Health

High Heterotrophic Plate Counts in treated drinking-water indicate inadequate treatment of the water, post-treatment contamination or bacterial after growth in the distribution system. Therefore, pathogenic micro organisms could possibly be present in the water and pose a health risk when the water is used for domestic consumption.

SANS 241 Standards

  • SANS 241 Table C.3 (Operational water quality alert values) Column 3, Alert level (Upper Limit): 5000 (count per mL)

Possible reason/s for failure

  • No disinfection (e.g. no chlorine dosing, no ozone dosing, no UV system)
  • No residual chlorine or low level of residual chlorine (e.g. chlorine not added at plant, residual chlorine below 0.2 mg/L at point of consumption)
  • Contamination (e.g. from pipe breaks and bursts, from repairs to network, infiltration or seepage from a contaminated source, sewage near groundwater sources, contamination from pit latrines/septic tanks, rubbish and faecal matter around standpipes)
  • Lack of maintenance (e.g. reservoirs and pipes not cleaned/flushed)
  • Poor design (e.g. long retention times in reservoir and distribution network, open reservoirs, large reticulation network with no additional chlorine dosing at reservoirs)
  • Sabotage/vandalism

[Total] coliform bacteria

The total coliform group includes bacteria of faecal origin and several other bacterial groups.

Effect and possible implications of failure

  • Health

Total coliforms are indicative of the general hygienic quality of water and are primarily used in the evaluation of the operational efficiency of water treatment processes. They also indicate microbial growth in the distribution system or post-treatment contamination of drinking water. As the total coliform group includes bacteria of faecal origin and indicates the possible presence of bacterial pathogens such as Salmonella spp., Shigella spp., Vibrio cholerae, pathogenic E. coli, etc, high total coliform counts can be responsible for diseases such as gastroenteritis, salmonellosis, dysentery, cholera and typhoid fever.

SANS 241 Standards

  • SANS 241 Table C.3 (Operational water quality alert values) Column 3, Alert level (Upper Limit): 10 (count/100 mL)

Possible reason/s for failure

  • No disinfection (e.g. no chlorine dosing, no ozone dosing, no UV system)
  • No residual chlorine or low level of residual chlorine (e.g. chlorine not added at plant, residual chlorine below 0.2 mg/L at point of consumption)
  • Contamination (e.g. from pipe breaks and bursts, from repairs to network, infiltration or seepage from a contaminated source, sewage near groundwater sources, contamination from pit latrines/septic tanks, rubbish and faecal matter around standpipes)
  • Lack of maintenance (e.g. reservoirs and pipes not cleaned/flushed)
  • Poor design (e.g. long retention times in reservoir and distribution network, open reservoirs, large reticulation network with no additional chlorine dosing at reservoirs)
  • Sabotage/vandalism

Somatic Coliphages

Somatic coliphages are a diverse group of phages which infect E.coli and certain closely related bacteria. These phages occur in large numbers in sewage and therefore the presence of somatic coliphages indicates faecal pollution.

Effect and possible implications of failure

  • Health

Viruses are important causative agents of waterborne disease and can cause illness such as gastroenteritis, hepatitis, poliomyelitis and respiratory illness.

SANS 241 Standards

  • SANS 241 Table C.3 (Operational water quality alert values) Column 3, Alert level (Upper Limit): 1 (count/10 mL)

Possible reason/s for failure

  • No disinfection (e.g. no chlorine dosing, no ozone dosing, no UV system)
  • No residual chlorine or low level of residual chlorine (e.g. chlorine not added at plant, residual chlorine below 0.2 mg/L at point of consumption)
  • Contamination (e.g. from pipe breaks and bursts, from repairs to network, infiltration or seepage from a contaminated source, sewage near groundwater sources, contamination from pit latrines/septic tanks, rubbish and faecal matter around standpipes)
  • Lack of maintenance (e.g. reservoirs and pipes not cleaned/flushed)
  • Poor design (e.g. long retention times in reservoir and distribution network, open reservoirs, large reticulation network with no additional chlorine dosing at reservoirs)
  • Sabotage/vandalism

Cytopathogenic Viruses

Human viruses require man as their specific host and are primarily transmitted by the faecal-oral route (transmission by faecally contaminated water or food). The virus group includes enteroviruses (polio, coxsackie A and B and echo viruses), enteric adenoviruses, reoviruses, rotaviruses, hepatitis A and E viruses, calciviruses and astroviruses.

Effect and possible implications of failure

  • Health

Possible health effects associated with the presence of such viruses in water includes paralysis, meningitis, hepatitis, respiratory illness and diarrhoea.

SANS 241 Standards

  • SANS 241 Table C.3 (Operational water quality alert values) Column 3, Alert level (Upper Limit): 1 (count/100 mL)

Possible reason/s for failure

  • No disinfection (e.g. no chlorine dosing, no ozone dosing, no UV system)
  • No residual chlorine or low level of residual chlorine (e.g. chlorine not added at plant, residual chlorine below 0.2 mg/L at point of consumption)
  • Contamination (e.g. from pipe breaks and bursts, from repairs to network, infiltration or seepage from a contaminated source, sewage near groundwater sources, contamination from pit latrines/septic tanks, rubbish and faecal matter around standpipes)
  • Lack of maintenance (e.g. reservoirs and pipes not cleaned/flushed)
  • Poor design (e.g. long retention times in reservoir and distribution network, open reservoirs, large reticulation network with no additional chlorine dosing at reservoirs)
  • Sabotage/vandalism

Protozoan Parasites (Giardia/Cryptosporidum)

Giadia and Cryptosporidium are pathogenic parasites that are commonly found in lakes and rivers, particularly those contaminated by sewage and animal wastes. They exist as a cyst; an egg-shell-like covering that protects the micro organism from hazards (e.g. conventional disinfection methods using chlorine may be ineffective). The cyst also protects the micro organism from destruction outside the host, leaving it viable. When this is ingested, viable cysts can infect their new hosts.

Effect and possible implications of failure

  • Health

Cryptosporidium/Giardia has been recognised as a waterborne pathogen in recent years, with the oocysts of Cryptosporidium and cysts of Giardia being infective to man. Infection occurs by ingestion of oocysts/cysts and disease takes the form of gastroenteritis, diarrhoea, vomiting, etc. Acute, chronic and asymptotic manifestations of infection are known. The infective dose for parasites is extremely low. Theoretically, one oocyst/cyst would be sufficient to cause infection.

SANS 241 Standards

  • SANS 241 Table C.3 (Operational water quality alert values) Column 3 Alert level (Upper Limit): 1 (count/10 mL)

Possible reason/s for failure

  • Selection of ineffective treatment process (e.g. disinfectants such as chlorine, hydrogen peroxide, chlorine dioxide and ozone are not really effective for the inactivation of protozoan parasites, no UV system, no slow sand filters)
  • Contamination (e.g. from pipe breaks and bursts, from repairs to network, infiltration or seepage from a contaminated source, sewage near groundwater sources, contamination from pit latrines/septic tanks, rubbish and faecal matter around standpipes)
  • Sabotage/vandalism

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