25th June 20192nd July 20199th July 201916th July 201923rd July 201930th July 20196th August 201913th August 2019
uMsunduzi at Caluza Bridge435221873076290919863292029205794
uMsunduzi below Kwapata345034105172517223102419657947760
uMsunduzi at Edendale Weir3282365414830663049605830906010500
Slangspruit above Duzi confluence2063026130285102851051720198630836027550
Duzi at Camps Drift Bridge63801046211199613110462686716693076
uMsunduzi above Dorpspruit confl24009091160816436544959071236
Dorpspruit just above Townbush stream16009591039228251721413668671789
Townbush Stream just above Dorpspruit160056541061732938730387304101956
Dorpspruit Ohrtmann Road / just above Duzi confluence77106830677020350111907380275508010
uMsunduzi above Refuse Dump37843654148321876867727014012489
uMsunduzi above Darvill WWW26021607920832554352172334486131
uMsunduzi U/S Baynespruit307618502063206351741413614805794
Baynespruit at Greytown Road344804460759057104611064406440487
Baynespruit behind Epol43520235901299701187057940135401081030760
Baynespruit at Sobantu131700201400648800344800307600307600727000488400
uMsunduzi U/S Darvill mat river648806867068670579407701086640>24196129970
Darvill Final Effluent normal discharge site15292953784311483311012
uMsunduzi D/S Darvill mat river3255086640
uMsunduzi at Motorcross weir103909070798043205810630441>24196

 


WHAT DO E. COLI NUMBERS MEAN?

DUCT’s River Water Quality Assessment Guidelines updated 27 October 2013

E. coli bacteria occur naturally within mammal digestive systems and most of them are not harmful in any way. However, because they are so common E. coli data are considered useful as a general indicator of a wide range of other potential human pathogens, and thus also of the possible presence of sewage related water quality problems. In the absence of other data, E. coli numbers are useful in allowing a general assessment of other potential water quality risks.

E. coli count/100mL
Water quality “assessment”
Assessment of probable risk to canoeists

*0 – 130
  WaterExcellent Excellent – Considered acceptable for full contact recreation – excellent / likely natural catchment.
Extremely low risk.

130 – 1000
WaterGood Good – within the range expected for quite good catchment conditions, but significant / increasing risk of illness if used for full contact recreation (e.g. swimming). Very low risk.

1001 – 4000
WaterFair Fair resource condition, natural sources (i.e. not sewage related) are still possibly the E. coli source, but increasing likelihood of human faecal / sewage contamination at the upper end of this range. Unacceptable for swimming. Low, but increasing risk.

4 001 – 10 000
WaterPoor Degraded – Significant faecal input or some sewage contamination is indicated. Other water quality parameters are likely to be poor.
Moderate risk (approx. 1 in 10 may get sick).

10 001 – 25 000
WaterVeryPoor Unacceptably Poor, sewage contamination definitely present.
Moderately high canoeing risk (approx. 1 in 5 may get sick) – some likelihood of illness esp. in white water.

25 001 – 50 000
WaterDangerous Bad, with significant sewage contamination and negative environmental consequences.
High risk (approx. 1 in 3 may get sick) – consider not canoeing or paddle on flat water only, with no risk of falling out.

>50 000
WaterVeryDangerous Severely contaminated with significant sewage contamination and negative environmental consequences.
Very High canoeing risk – (approx. 1 in 2 paddlers may get sick). Avoid canoeing!

*Note, the only acceptable value for drinking water quality is ZERO E.coli counts per 100 mℓ. No naturally occurring surface water should be expected to have E. coli this low (even in large dams). If zero E. coli results are achieved for a natural water, contamination by disinfectants is the likely cause and this may be masking other significant potential pollutants.