Compiled by Mercia Volschenk on behalf of Scientific Services
| Name | Description | CSS Longitude | CSS Latitude |
|---|---|---|---|
| DR01 | Disa River near Princess St | 18.35615 | -34.041973 |
| DR02 | Disa River at Victoria Road | 18.353663 | -34.030312 |
| DR04 | Disa River at Longkloof Road | 18.388277 | -34.01142 |
| DR05 | Hout Bay River estuary | 18.355065 | -34.045425 |
| DR06 | Disa River at Bethal Road | 18.366313 | -34.019345 |
| Sampled Date | DR01 | DR02 | DR04 | DR5 | DR06 |
|---|---|---|---|---|---|
| 09/01/2018 | 250000 | 2900 | 90 | 710 | |
| 06/02/2018 | 1400 | 100000 | 65 | 69000 | 65 |
| 06/03/2018 | 600 | 1300 | 220 | 286 | 74 |
| 08/05/2018 | 82000 | 36000 | 490 | 13400 | 3200 |
| 28/06/2018 | 35 | 36000 | 40000 | 180 | 110 |
| 26/07/2018 | 4400 | 15000 | 150 | 20 | 2700 |
| 28/08/2018 | 20000 | 46000 | 6500 | 78 | 240 |
| 18/09/2018 | 27000 | 34000 | 190 | 10000 | 2400 |
| 02/10/2018 | 100000 | 1000000 | 100 | 10000 | 2100 |
| 08/11/2018 | 2700 | 16000 | 71 | 40000 | 92 |
| 06/12/2018 | 680000 | 470000 | 10000 | ||
| 10/01/2019 | 3500 | 60000 | 150 | 10 | 18 |
| 07/02/2019 | 1200 | 900 | 370 | 140 | 1400 |
| 05/03/2019 | 4000 | 860 | 200 | 2900 | 410 |
| 02/04/2019 | 41000 | 6900 | 240 | 16000 | 210 |
| 07/05/2019 | 330000 | 69000 | 580 | 2100 | 60 |
| 04/06/2019 | <100 | 700 | 800 | 3900 | 340 |
| 02/07/2019 | 2100 | 2800 | 50 | 4100 | 54 |
| 06/08/2019 | 10000 | 100000 | 130 | 25000 | 150 |
| 03/09/2019 | 36000 | 100000 | 30 | 5400 | 7600 |
| 01/10/2019 | 7200 | 6000 | 140 | 3500 | 340 |
| 05/11/2019 | 4300 | 4400 | 40 | 840 | 170 |
| 02/12/2019 | 4300 | 1600 | 1800 | ||
| 02/01/2020 | 1000000 | 1000000 | 530 | 2200 | 210 |
| 04/02/2020 | 100000 | 100000 | 99 | 80 | 68 |
| 03/03/2020 | 7400 | 1000000 | 240 | 100000 | 81 |
| 08/04/2020 | 710000 | 100000 | 98000 | ||
| 13/05/2020 | 2100 | 4600 | 100 | 1000 | 70 |
| 01/06/2020 | 9200 | 1000 | 190 | 6000 | 170 |
| 02/07/2020 | 5400 | 1500 | 200 | 1300 | 300 |
| 04/08/2020 | 1900 | 21000 | 180 | 3300 | 140 |
| 01/09/2020 | 100000 | 35000 | 50 | 10000 | 45 |
| 01/10/2020 | 67000 | 9000 | 50 | 75000 | 65 |
| 05/11/2020 | 100000 | 24000 | 210 | 100000 | 470 |
| 07/12/2020 | 1000000 | 100000 | 960 | 1000000 | 570 |
| 11/01/2021 | 1000000 | 100000 | 90 | 510000 | 50 |
| 08/02/2021 | 360000 | 2500 | 47 | 420000 | 340 |
| 08/03/2021 | 660000 | 10000 | 3400000 | 200 | 200 |
| 10/03/2021 | 100000 | 5000 | |||
| 08/04/2021 | 7000 | 8400 | 1000 | 10000 | 380 |
| 06/05/2021 | 10000 | 100000 | 9600 | 100000 | 10000 |
| 03/06/2021 | 320000 | 67000 | 80 | 41000 | 110 |
| 01/07/2021 | 86000 | 72000 | 520 | 390000 | 1900 |
| 05/08/2021 | 1000000 | 100000 | 270 | 660000 | 480 |
| 02/09/2021 | 720000 | 100000 | 520 | 460000 | 300 |
| 14/10/2021 | 1000000 | 330000 | 1060 | 1000000 | 7100 |
The National Resource Water quality objectives for the Berg Catchment was promulgated in November 2020. Section B (iv): RQOs will apply from the date signed off as determined in terms of Section 13(1) of the National Water Act, 1998, unless otherwise specified by the Minister.
The NRQO stipulates for the Houtbay catchment that for Escherichia coli concentrations of waterborne pathogens for full contact recreation should be maintained at ≤ 1065 counts/100ml (95th percentile).
The Table below provides the compliance summary with the NRQO limits.
| Sampling Site | DR01 | DR2 | DR04 | DR05 | DR06 |
|---|---|---|---|---|---|
| Percentile | 95 | 95 | 95 | 95 | 95 |
| Minimum data points needed | 10 | 10 | 10 | 10 | 10 |
| Number data points you have | 45 | 46 | 43 | 44 | 42 |
| Data minimum | 35 | 700 | 30 | 10 | 18 |
| Data maximum | 1000000 | 1000000 | 3400000 | 1000000 | 10000 |
| Hazen result | 1000000.00 | 1000000.00 | 20239.95 | 761999.74 | 7300.00 |
Table 3: Houtbay Catchment Hazen results January 2018 – October 2021
