Established in 1987, GCS (Pty) Ltd is an independent consultancy offering a wide range of professional services within the fields of water and environmental sciences. As an employee-owned company GCS is committed to providing clients with quality services and leading products. With offices in Johannesburg, Durban and Pretoria ( South Africa ), Gaborone ( Botswana ), Windhoek ( Namibia ), Lusaka ( Zambia ) and Ostrava ( Czech Republic ), GCS boasts international experience, including 29 African countries.

GCS has 70 professional staff and a total staff compliment of 100. Its highly trained employees are skilled, committed and registered with the relevant industry associations to ensure appropriate standards, ethics, accountability and integrity.


Vision & Mission

GCS’s vision is to provide professional and cost-effective consulting services. Since its inception the company has established long-standing relationships with many of its clients and continuously delivers client satisfaction in terms of quality and product delivered on time and on budget. GCS aims to continuously grow and adapt according to the needs of both the market and the clients.


  • GCS was founded in 1987 by Andrew Johnstone after Dames and Moore South Africa had disinvested from South Africa.
  • The company was initially established to provide groundwater-related studies. It has subsequently expanded its focus and now also offers Hydrology, Hydrogeology, Pedology, Geology, Engineering, Geotechnical and Environmental Sciences.
  • Our head office is based in Johannesburg, with other operations in Durban and Pretoria as well as in Lusaka (Zambia), Windhoek (Namibia) and Ostrava (Czech Republic).
  • GCS operates throughout Africa.
  • While the majority of our work comes from the mining sector, GCS also operates in the private, industrial and oil and gas sectors, as well as government industries.

Social Responsibility

GCS does far more than merely paying lip service to corporate social responsibility and investment, and over the years have been involved in a number of meaningful, impactful  and sustainable CSI initiatives. We have endeavoured over the last few years to make our presence felt in the community in terms of positive environmental training.

GCS Internal Training and Awareness Programme

Employees are required to provide in-house training to the rest of the staff compliment to ensure all staff members are aware of the latest development in our field. These training sessions occur on a Friday and are generally informal. Topics have included a though coverage of the Department of Water Affairs Best Practice Guidelines (over a number of sessions), Environmental Sustainability training, updates on the new waste legislation and other relevant legislation coming into effect, latest developments in terms of Geographic Information Systems (GIS) and many more.

These talks allow for staff from different units within GCS, namely Water, Environmental and GIS, to get a more holistic view on the field of environmental consulting and all the latest legislative and other developments.

Molweni River Water Health Project

The company has a long-standing partnership with the Kloof Conservancy where it is involved in a River Water Health Project in the Molweni RIver catchment area. The project initially involved seven high schools in the Kloof/Hillcrest area as well as the Molweni. GCS was one of a number of organisations involved in this project. Its role involved bi-annual hands on training at the river sites in terms of bio-monitoring and general water quality issues. More recently, GCS sponsored a water table at the 2016 Kwa-Ximba Trail Run, an event run in aid of local environmental projects.

Golden Harvest Park River Clean-Up

In 2013, staff volunteered for the annual Golden Harvest Park Clean-Up day where it was involved in the clearing of the park in terms of the litter and alien invasive plants. Part of the GCS team included qualified hydrologists who provided advice on water management and dam maintenance. The company also assisted with advice on the water quality results previously received by the community and took in-situ measurements on the day. An accredited biomonitoring practitioner from GCS conducted a basic invertebrate assessment (SASS5) for the community.

Noah’s Ark Orange Farm

GCS has been involved with Noah’s Ark Orange Farm, an aftercare facility for children in the Orange Farm community, since June 2012 when we developed a vegetable garden through Food and Trees for Africa and helped connect the toilet facilities at the site. The daily meal provided to the children has been supplemented by the vegetable garden. In 2013, we supplied back to school stationary packs for each of the children while a golf day celebrating the company’s 25th anniversary raised money for Noah’s Ark Orange Farm.

Barnato High School

Over the years, GCS has made various monetary contributions to Barnato High School in Berea, Johannesburg. In 2012, its contribution went towards fixing a damaged roof while 2013’s contribution contributed to buying benches for the school hall and new desktops for desk frames.

Nelson Mandela Day and Santa Shoebox

Since 2011, GCS staff have participated in the Knit-a-Square project on Nelson Mandela Day (18 july). In 2017, GCS donated chairs and tables to the Alexandra Disability Home on Mandela Day. In October of each year, GCS does a collection for Santa Shoebox.

Education Sponsorship

Since 2016, GCS has funded the education of an under privileged child attending the iThemba Academy situated near the valley of the 1000 Hills.

Company culture

GCS employs a high calibre of professional staff and encourages a culture of continuous learning and development. As a result,  the company has developed leading edge specialists in numerous areas of expertise, many of whom are recognised as amongst the most knowledgeable in their fields both locally and internationally.

Since 1987, GCS specialists have presented papers and presentations at more than 34 conferences and symposiums locally and globally, including numerous groundwater, mining and environmental conferences. Employees have also submitted a number of papers to reputable industry publications.

“We are a dynamic company that adapts quickly to market needs and aims to create a company culture that encourages professional growth and development. GCS employs staff who share this vision and who are assured in the knowledge that creativity, drive and their own standards of personal excellence are only limited by how far and fast they can move. Our core values are honesty, trust and commitment. We believe in treating others with dignity and respect and expect our people to walk the talk in terms of quality, standards, ethics, professionalism, morals and integrity”