FNB Dusi Canoe Marathon

16-18 February 2017

Water Quality

Site29 Dec 165 Jan 1710 Jan 1717 Jan 1724 Jan 1731 Jan 177 Feb
uMsunduzi at Caluza Bridge4101190260234482481770112033
uMsunduzi below Kwapata<1000<10001119919863648851728664
uMsunduzi at Edendale Weir41086015290133405830155317270
Slangspruit above Duzi confluence5207405040240020109334884
Duzi at Camps Drift Bridge4226095172141367541732909
uMsunduzi above Dorpspruit confl1299759890678960124009804
Dorpspruit just above Townbush stream17329768027552755191848844884
Townbush Stream just above Dorpspruit13130248916641732914833890090700
Dorpspruit Ohrtmann Road / just above Duzi confluence17329085501497026020307601223027550
uMsunduzi above Refuse Dump155316867579448842909241967270
uMsunduzi above Darvill WWW129978164No accessNo accessNo accessNo accessNo access
uMsunduzi U/S Baynespruit1203310462313048842481365424196
Baynespruit at Greytown Road>2419667601374088205290820010460
Baynespruit behind Epol>2419603103230754018500789023820
Baynespruit at Sobantu203002000>241960307600906001203300435200
uMsunduzi U/S Darvill mat river26025794461138735475435217329
Darvill Final Effluent normal discharge site2593141912637974>4800
uMsunduzi D/S Darvill mat river260219863
uMsunduzi at Motorcross weir1918034482723360938731209804

 


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.

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