Tobie Louw attended the Quarterly Hermanus Monitoring Committee (HMC) as representative of HRA, and shares high level feedback on the management of this important water source.
Attendance to Quarterly Hermanus Monitoring Committee (HMC)
I regularly attend these meetings as representative of Hermanus Ratepayers Association, with the objective to share high level feedback on the management of this important water source.
Wellfields need very regular monitoring to ensure sustainable delivery. Umvoto, an earth-science consultancy are responsible for the establishment of these wellfields. They still perform ongoing monitoring duties of the boreholes. On a quarterly basis Umvoto gives feedback via a selected committee, the Hermanus Monitoring Committee (HMC), on the monitoring and performance of the wellfields.
A short summary on the report back:
Water demand projections for Greater Hermanus
The Preekstoel Water Treatment Works (WTW) currently receives about 64% of its annual raw water from the De Bos Dam. The remaining 36% is being supplied from groundwater. This is drawn from two wellfields. Gateway Wellfield currently contributes about 16% of the total volume and Hemel and Aarde Wellfield 20%. Each wellfield includes several production and monitoring boreholes. The wellfield contribution has over the past year therefore increased from 27% to 36%.
Gateway Wellfield
It entails 3 production boreholes with an approximate total 9-month yield to end July 2026 of 695 000 cubic meter. This represents 43% of the allocated Water Use Licence for the Gateway Wellfield. Implying that there can be more abstraction, provided the yield proves sustainable.
Additionally, there are some 22 monitoring boreholes that serve the Gateway Wellfield, some near- and other far-field. Groundwater levels within the vicinity of the Gateway Wellfield remain stable and do not indicate any significant impacts on other groundwater users in the area.
Lastly, as for 2025, an overview of the Gateway Wellfield hydrochemistry (metals and microbiology) did not reveal any concerning results from monitoring over this period.
Hemel and Aarde Wellfield
This is in fact a collective name for two wellfields, ie the Camphill and the Volmoed wellfields. Together they include 8 production boreholes with an approximate total 9-month yield to end July 2026 of 843 000 cubic meter. This represents 70% of the Stage 2 Water Use Licence for the Hemel and Aarde Wellfield.
There are 7 monitoring boreholes that serve the Hemel and Aarde Wellfield. There were no issues of concern noted regarding flow rates and ground water levels in the 8 production boreholes across the Hemel en Aarde Wellfield.
These wellfields’ hydrochemistry also did not reveal any concerning results during monitoring.
Treated Wastewater used for Irrigation.
Overstrand Municipality distribute treated wastewater for the irrigation of various sports fields and the golf course in Hermanus. Overstrand Municipality has a Water Use Licence to allow the irrigation of treated effluent to these various sports fields. Umvoto monitors the impact of these applications via 12 monitoring boreholes, together with several private boreholes, spread across the areas of application.
Similar to 2025 there were some minor exceedances from National Standards, however these were geogenic and no clear indication of upper aquifer groundwater contamination was identified.
Ecological Monitoring of Fernkloof Nature Reserve
Umvoto also does ecological monitoring in the Fernkloof Nature Reserve, which is the Peninsula Aquifer recharge area for both Gateway and Volmoed Wellfields. Three ecological wetland sites were selected for this monitoring. These sites are linked to springs and seeps within Fernkloof Nature Reserve. Several parameters are monitored at these three sites to assist in tracking any impacts of large-scale abstraction for Hermanus municipal use. This includes tracking of the health of Berzelia communities (an indicator species typical to Fernkloof montane wetlands) across three defined monitoring transects.
From these reviews, it was found that that there were no significant trends or anomalies noted at the Fernkloof Nature Reserve ecological monitoring transects. Monitoring is based on satellite and drone imagery, as well as on site surveys.
Quality monitoring of treated water downstream of Preekstoel water treatment works
Umvoto also reported on the quality of Hermanus drinking water and presented the tests results compared to the statutory limits. The water treated at the Preekstoel water treatment works complies with the stipulated norms.
Closing remarks
The meeting was well attended by representatives of Overstrand Municipality’s infrastructure directorate as well as the Overberg Geoscientists group. Also, several representatives of some Hemel en Aarde properties and farms. Peter van Niekerk of Onrus Estuary Forum is the chairperson of the HMC.
As before I found the feedback information very well prepared and professionally presented by Umvoto.
The monitoring of our well fields is in my view still under good management. From the current usage data, it is evident that there is still additional capacity within the two groundwater use licences, which can be utilised through increased extraction.
However, I do feel that the development of the third source, that is a plant to desalinate sea water, needs to get high priority from Overstrand Municipality. It requires several items that need to be in place before construction can commence. These include aspects such as securing of land, servitudes and other statutory approvals, which often tend to take longer than anticipated.
Prepared by Tobie Louw for HRA
