Paarl is the largest town in the Drakenstein Municipality, Western Cape. The area also includes that also encompasses Wellington, Gouda and Saron. The town is situated at the foot of the Paarl Mountain, 60kms outside Cape Town, and is cut through by the Berg River. Vineyards, orchards, and wheat lands surround the area. In recent years the population has grown, businesses have expanded, expand, the population grows, and along with a concomitant growth in it the residential areas.
Previously, Paarl purchased 95% of its clean water from the City of Cape Town, which is sourced from the Wemmershoek Dam. Almost entirely dependent on this single water supply, but this proved to be is very expensive. and they were. Paarl did have its own water supply scheme in place – which consisted of two bulk dams that captured natural run-off water from the Paarl Mountain – however no water treatment facilities existed, meaning that the water was unsafe for residents to drink. This natural water supply from Paarl Mountain had been supplying residents and farmers since early settlement days. The Meulwater Water Treatment Works program tackled the issue of taking local water supplies and finding a way to treat with a cost-effective and efficacious programme.
In May 2012, the Drakenstein Municipality commissioned the construction of an 8Ml/day water treatment works on Paarl Mountain. The plant’s facilities include process units, laboratory facilities, chemical dosing and machine room, a raw water pipeline, a treated water pipeline, a pipeline to convey residual solids down the mountain, a sewage system, landscaping, roadwork’s, and ancillary work.
This treatment plant is notable for a variety of various ingenious methods and unique features. One of the more rarer practices found here is the direct filtration process that allows the plant’s environmental footprint to be minimised. The reduced footprint is an important factor, taking that takes into account that fact that the facility is built on the border of the Paarl Mountain Nature Reserve. The environmentally friendly design has also led to substantial savings in initial capital cost.
This innovative cost-saving mindset was extended to the issue of water losses, which is the amount of treated water that does not reach the customer. In 1999, within the Drakenstein Municipality, 34% was mislaid in water losses. An action plan was created to reduce this level within the municipality through several administrative tasks. This plan utilized pressure management to reduce losses on leaks during certain times of the day, expanded metering to all un-metered water connections, placed an emphasis on detecting and quickly repairing leaks, and a led public awareness campaign on ways to reduce losses in water supplies. This coordinated action plan reduced the water losses to 12.1% in 2013, which is substantially lower than the national average of 36.2%
One of the most important aspects of the design at Meulwater is the design of the system for cleaning the filter. This feature is especially important for the deep-bed direct filtration plant, ensuring that the entire depth of the bed is cleaned with minimal loss of water. Other notable design firsts for a South African water treatment plant are enhanced dosing controls mechanisms, ‘green’ roofs, an operator-friendly layout, and environmentally sensitive aesthetics which allow the plant to further blend into the environment around it.
Estimates from the municipality show that the treatment costs at the plant are at R2.11/kl, which is significantly lower than the R3.42/kl that the City of Cape Town charges the municipality for the sale of water. This new water supply is able to treat between 1650Ml and 2900Ml annually, providing 15%-26% of Paarl’s water. Due to these drastic successes and innovative designs, this plant has received numerous accolades and awards like the Institute for Mechanical Engineering South Africa (IMESA) environmental award; it also was a finalist in the technical excellence category in Civil Engineering magazine. Meulwater Treatment Works is conceivably the most technologically advanced, cost-effective, and environmentally friendly small-scale water treatment process in South Africa.