 |
Liffey Stream Test Results
Date: Thursday 6th Oct 2011
Weather: Overcast, no wind, air temperature 11 degrees, rain in the previous few days. Place of test: 2468453E, 5729808N Near North Belt Bridge
| Test |
Excellent |
Satisfactory |
Unsatisfactory |
 |
Results |
Quality |
| pH |
7.8 |
6.5 - 8.9 |
Less than 6.5 or more than 9 |
6.90 |
Satisfactory |
| Conductivity (µS/cm) |
Less than 100 |
100 - 500 |
More than 500 |
263 |
Satisfactory |
| Dissolved Oxygen (mg/L) |
|
|
|
8.20 |
|
| Oxygen Saturation (%) |
More than 90 |
80 - 90 |
Less than 80 |
72.10 |
Unsatisfactory |
| Nitrate (mg/L) |
Less than 0.15 |
0.15 - 0.5 |
More than 0.5 |
3.10 |
BAD Very Degraded |
| Phosphate (mg/L) |
Less than 0.01 |
0.01 - 0.03 |
More than 0.03 |
0.45 |
Unsatisfactory |
| Turbidity (NTU) |
Less than 2 |
2.5 |
More than 5 |
0.14 |
Excellent |
| Temperature (°C) |
|
|
|
12.20 |
|
| Coliformes |
0-50 |
201-600 |
601-2000 |
413 |
Satisfactory |
| E.Coli |
|
|
|
72 |
Excellent |
| Salmonella |
|
|
|
36 |
Excellent |
| |
|
|
|
|
|
Conclusions:
Overall water quality ranking using macro invertebrate indicators: medium
Overall water quality ranking: Satisfactory
|
Additional
Comments:
The Lincoln Environmental Organisation (LEO) helped by WaterWatch tested the Liffey stream on the 6th October 2011. We have been testing it for the last few years. We found that from the indicator invertebrates, the longer term water quality was “medium”, the dissolved nitrate level was 3.1mg/L which was lower than in April when it was 5.1 mg/L but it was still more than 6 times worse than unsatisfactory and the phosphate level was also was very high at 0.45 mg/L. Last year the indicator invertebrates showed the lowest number of species we had ever seen (only 2), this year in April, 6 species were found, this time, in October, 5 species were found.
Note: The oxygen level depends a lot on the conditions on the day, such as how fast the water is flowing and how windy it is.
Note: The E.coli count (with each colony corresponding to one bacterium in the sample) were graded using the Microbiological Water Quality Guidelines for Marine and Freshwater Recreational Areas, although only one sample was tested.
Published in June 2002 by the Ministry for the Environment Manatu Mo Te Taiao PO Box 10-362, Wellington, New Zealand. Updated in June 2003. ISBN: 0-478-24091-0 ME number: 474.This document is available under publications on the Ministry for the Environment’s website: www.mfe.govt.nz
E. coli is used as an indicator of contamination of drinking-water by faecal material. The Maximum allowed for E. coli is less than 1 E. coli in 100 mL of sample. Drinking-water Standards for New Zealand 2005
|
Date: Wednesday 11th May 2011
Weather: Overcast
| Test |
Excellent |
Satisfactory |
Unsatisfactory |
|
Results |
Quality |
| pH |
7.8 |
6.5 - 8.9 |
Less than 6.5 or more than 9 |
6.90 |
Satisfactory |
| Conductivity (µS/cm) |
Less than 100 |
100 - 500 |
More than 500 |
260 |
Satisfactory |
| Dissolved Oxygen (mg/L) |
|
|
|
8.90 |
|
| Oxygen Saturation (%) |
More than 90 |
80 - 90 |
Less than 80 |
90.00 |
Satisfactory |
| Nitrate (mg/L) |
Less than 0.15 |
0.15 - 0.5 |
More than 0.5 |
5.10 |
BAD Very Degraded |
| Phosphate (mg/L) |
Less than 0.01 |
0.01 - 0.03 |
More than 0.03 |
0.05 |
Unsatisfactory |
| Turbidity (NTU) |
Less than 2 |
2.5 |
More than 5 |
0.00 |
Excellent |
| Temperature (°C) |
|
|
|
14.70 |
|
| Coliformes |
0-50 |
201-600 |
601-2000 |
138 |
Excellent |
| E.Coli |
|
|
|
13 |
Excellent |
| Salmonella |
|
|
|
13 |
Excellent |
| |
|
|
|
|
|
Conclusions:
The Lincoln Environmental Organisation (LEO) helped by WaterWatch tested the Liffey stream on the 11th April. We have been testing it for the last few years. We found that from the indicator invertebrates, the water was “good”, as were most of the indicators, which was quite a difference form previous years. This might have been due to no recent rain and to the fact the sampling was done near a spring. However the dissolved nitrate level was 5.1 mg/L which is more than 10 times worse than unsatisfactory and the phosphate level was also was very high at 0.05 mg/L. The coli count was the lowest we have ever found it at 137.5 CFU’s per 100mL. Last year the results were 3281 CFU’s per 100mL, where over 2000 is counted as degraded.
Overall water quality ranking: Satisfactory
|
Additional
Comments:
Last year the indicator invertebrates showed the lowest number of species we had ever seen (only 2), this year 6 species were found. |
Date: Monday 3rd May 2010
Weather: Overcast, no wind, There had been below average rain all summer, and no recent rain.
| Test |
Excellent |
Satisfactory |
Unsatisfactory |
|
Results |
Quality |
| pH |
7.8 |
6.5 - 8.9 |
Less than 6.5 or more than 9 |
6.80 |
Satisfactory |
| Conductivity (µS/cm) |
Less than 100 |
100 - 500 |
More than 500 |
303 |
Satisfactory |
| Dissolved Oxygen (mg/L) |
|
|
|
7.36 |
|
| Oxygen Saturation (%) |
More than 90 |
80 - 90 |
Less than 80 |
69.90 |
Unsatisfactory |
| Nitrate (mg/L) |
Less than 0.15 |
0.15 - 0.5 |
More than 0.5 |
4.90 |
BAD Very Degraded |
| Phosphate (mg/L) |
Less than 0.01 |
0.01 - 0.03 |
More than 0.03 |
0.15 |
Unsatisfactory |
| Turbidity (NTU) |
Less than 2 |
2.5 |
More than 5 |
7.89 |
Unsatisfactory |
| Temperature (°C) |
|
|
|
12.80 |
|
| Coliformes |
0-50 |
201-600 |
601-2000 |
3281 |
Degraded |
| E.Coli |
|
|
|
24 |
Excellent |
| Salmonella |
|
|
|
19 |
Excellent |
| |
|
|
|
|
|
Conclusions:
The Lincoln Environmental Organisation (LEO) helped by LET and WaterWatch tested the Liffey stream on the 3rd May 2010. We have been testing it for the last few years. We found that from the indicator invertebrates, the water was “degraded”, the Dissolved Oxygen was only 69.9% which is “unsatisfactory”, the dissolved nitrate level was 4.0 mg/L which is 10 times worse than unsatisfactory, the dissolved phosphate levels were 0.15mg/L (anything higher than 0.5 is unsatisfactory).
The coli count was 3281 CFU’s per 100mL, where over 2000 is counted as degraded, however the count of E.coli and salmonella was very low, which was unusual, as it is usually high. This was probably because it has been very dry with no water runoff. The water in the stream would have come from the springs.
The indicator invertebrates showed the lowest number of species we had ever seen (only 2)
Overall water quality ranking: Degraded Poor
|
Additional
Comments:
|
Date: Saturday 4th Apr 2009
Weather: Fine with a light NE wind
| Test |
Excellent |
Satisfactory |
Unsatisfactory |
|
Results |
Quality |
| pH |
7.8 |
6.5 - 8.9 |
Less than 6.5 or more than 9 |
6.80 |
Satisfactory |
| Conductivity (µS/cm) |
Less than 100 |
100 - 500 |
More than 500 |
303 |
Satisfactory |
| Dissolved Oxygen (mg/L) |
|
|
|
8.47 |
|
| Oxygen Saturation (%) |
More than 90 |
80 - 90 |
Less than 80 |
77.50 |
Unsatisfactory |
| Nitrate (mg/L) |
Less than 0.15 |
0.15 - 0.5 |
More than 0.5 |
7.00 |
BAD Very Degraded |
| Phosphate (mg/L) |
Less than 0.01 |
0.01 - 0.03 |
More than 0.03 |
0.04 |
Unsatisfactory |
| Turbidity (NTU) |
Less than 2 |
2.5 |
More than 5 |
2.98 |
Satisfactory |
| Temperature (°C) |
|
|
|
14.80 |
|
| Coliformes |
0-50 |
201-600 |
601-2000 |
0 |
Not Tested |
| E.Coli |
|
|
|
0 |
Not Tested |
| Salmonella |
|
|
|
0 |
Not Tested |
| |
|
|
|
|
|
Conclusions:
Aquatic invertrabrates: Pollution tolerance rating: Poor
These results could point to the spring discharge coming from a shallow aquifer. As the nitrate levels from deeper wells are nowhere near this level.
Overall water quality ranking: Degraded Poor
|
Additional
Comments:
|
Date: Thursday 13th Nov 2008
Weather: Fine with light NE wind, no rainfall at least week before if not longer.
| Test |
Excellent |
Satisfactory |
Unsatisfactory |
|
Results |
Quality |
| pH |
7.8 |
6.5 - 8.9 |
Less than 6.5 or more than 9 |
7.00 |
Satisfactory |
| Conductivity (µS/cm) |
Less than 100 |
100 - 500 |
More than 500 |
230 |
Satisfactory |
| Dissolved Oxygen (mg/L) |
|
|
|
7.90 |
|
| Oxygen Saturation (%) |
More than 90 |
80 - 90 |
Less than 80 |
77.50 |
Unsatisfactory |
| Nitrate (mg/L) |
Less than 0.15 |
0.15 - 0.5 |
More than 0.5 |
2.00 |
BAD Very Degraded |
| Phosphate (mg/L) |
Less than 0.01 |
0.01 - 0.03 |
More than 0.03 |
0.37 |
Unsatisfactory |
| Turbidity (NTU) |
Less than 2 |
2.5 |
More than 5 |
2.00 |
Satisfactory |
| Temperature (°C) |
|
|
|
14.50 |
|
| Coliformes |
0-50 |
201-600 |
601-2000 |
1400 |
Unsatisfactory |
| E.Coli |
|
|
|
885 |
Excellent |
| Salmonella |
|
|
|
77 |
Excellent |
| |
|
|
|
|
|
Conclusions:
Aquatic invertrabrates used as environmental indicators:
Most dominant group: amphipods - Tolerance rating = Medium
Next most dominant group: segmented worms - Tolerance rating = Low
Overall water quality ranking: Degraded Poor
|
Additional
Comments:
As we have found last year a big increase in the nitrate levels from the small spring ! |
Date: Tuesday 22nd Apr 2008
Weather: Chilly southerly, fine with some cloud. Rained recently
| Test |
Excellent |
Satisfactory |
Unsatisfactory |
|
Results |
Quality |
| pH |
7.8 |
6.5 - 8.9 |
Less than 6.5 or more than 9 |
7.20 |
Satisfactory |
| Conductivity (µS/cm) |
Less than 100 |
100 - 500 |
More than 500 |
100 |
Satisfactory |
| Dissolved Oxygen (mg/L) |
|
|
|
8.64 |
|
| Oxygen Saturation (%) |
More than 90 |
80 - 90 |
Less than 80 |
78.30 |
Unsatisfactory |
| Nitrate (mg/L) |
Less than 0.15 |
0.15 - 0.5 |
More than 0.5 |
1.00 |
Unsatisfactory degraded |
| Phosphate (mg/L) |
Less than 0.01 |
0.01 - 0.03 |
More than 0.03 |
0.04 |
Unsatisfactory |
| Turbidity (NTU) |
Less than 2 |
2.5 |
More than 5 |
12.00 |
Unsatisfactory |
| Temperature (°C) |
|
|
|
10.60 |
|
| Coliformes |
0-50 |
201-600 |
601-2000 |
1400 |
Unsatisfactory |
| E.Coli |
|
|
|
885 |
Excellent |
| Salmonella |
|
|
|
77 |
Excellent |
| |
|
|
|
|
|
Conclusions:
Aquatic invertrabrates used as environmental indicators:
Most dominant group: amphipods - Tolerance rating = Medium
Next most dominant group: segmented worms - Tolerance rating = Low
Overall water quality ranking: Degraded Poor
|
Additional
Comments:
The water testing was arranged as part of the Lincoln Envirotown monitoring of Lincoln township.
The equipment and expertise was supplied by Lincoln University Waterwatch team run by Kelvin Nicolle.
Local residents, children, and visitors from Christchurch (Mr and Mrs Cargo aged 86) carried out the testing with help from the Lincoln University team and the High school LEO (Lincoln Environmental Organisation).
The results were generally very disappointing, although there was less phosphate than the previous testing, possibly because the recent rain diluted the water. The high nitrate and phosphate levels probably come from the spring water. |
Date: Tuesday 7th Aug 2007
Weather: Cloudy
| Test |
Excellent |
Satisfactory |
Unsatisfactory |
|
Results |
Quality |
| pH |
7.8 |
6.5 - 8.9 |
Less than 6.5 or more than 9 |
6.80 |
Satisfactory |
| Conductivity (µS/cm) |
Less than 100 |
100 - 500 |
More than 500 |
187 |
Satisfactory |
| Dissolved Oxygen (mg/L) |
|
|
|
9.30 |
|
| Oxygen Saturation (%) |
More than 90 |
80 - 90 |
Less than 80 |
87.10 |
Satisfactory |
| Nitrate (mg/L) |
Less than 0.15 |
0.15 - 0.5 |
More than 0.5 |
2.10 |
BAD Very Degraded |
| Phosphate (mg/L) |
Less than 0.01 |
0.01 - 0.03 |
More than 0.03 |
0.18 |
Unsatisfactory |
| Turbidity (NTU) |
Less than 2 |
2.5 |
More than 5 |
5.40 |
Unsatisfactory |
| Temperature (°C) |
|
|
|
11.70 |
|
| Coliformes |
0-50 |
201-600 |
601-2000 |
284 |
Satisfactory |
| E.Coli |
|
|
|
157 |
Excellent |
| Salmonella |
|
|
|
77 |
Excellent |
| |
|
|
|
|
|
Conclusions:
Aquatic invertrabrates used as environmental indicators:
Most dominant group: amphipods - Tolerance rating = Medium
Next most dominant group: segmented worms - Tolerance rating = Low
Overall water quality ranking: Degraded
|
Additional
Comments:
There had been heavy rain the previous day before this test. |
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