FNB Dusi Canoe Marathon

15-17 February 2018

Water Quality

Site2 Jan9 Jan16 Jan23 Jan30 Jan6 Feb13 Feb20 Feb
uMsunduzi at Caluza Bridge22472310579475406488173082002755
uMsunduzi below Kwapata6970139601553119863>241964611014136092080
uMsunduzi at Edendale Weir62408130259013760238201145061310310
Slangspruit above Duzi confluence435207270019863027230115305370241960>241960
Duzi at Camps Drift Bridge123304106>241966830359022470218702060
uMsunduzi above Dorpspruit confl2990112654518506694884173290959
Dorpspruit just above Townbush stream2755062002359012033025602010238001100
Townbush Stream just above Dorpspruit7080464038730744075402780171001090
Dorpspruit Ohrtmann Road / just above Duzi confluence22820290901169077010>24196032700402004640
uMsunduzi above Refuse Dump4884547538731299736545794920802481
uMsunduzi above Darvill WWWno accessno accessno access437019356270980403680
uMsunduzi U/S Baynespruit396863109804020980443024901119902460
Baynespruit at Greytown Road1460043520776014210960012010517204410
Baynespruit behind Epol109029870932016640932035903076011120
Baynespruit at Sobantu3140088200579400686700435200727000233300133400
uMsunduzi U/S Darvill mat river>24196387301203301553101732902098011199024000
Darvill Final Effluent normal discharge site19863187201528108193120437
uMsunduzi D/S Darvill mat river2419668670
uMsunduzi at Motorcross weir11199198637270>24196648826021553105910

 


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.

Dusi Canoe Marathon © 2017 A Gameplan Media website