The Kaaimans Raw Water Pump Station pumps water from the Kaaimans River to the Garden Route Dam. The Pump Station is situated adjacent to a 7m deep weir in the Kaaimans River. This weir forms a pool and water flows from the pool through two coarse screen openings into the pump sump.
The George Municipality replaced the existing six borehole pumps that were prone to blockage and damage caused by the sand pebbles, leaves, twigs and other fine river debris.
The required flow range for the Kaaimans Pump Station is a minimum of 15 l/s and a maximum of 230 l/s at 120 m total head and still allowing a minimum environmental flow of 35 l/s down the river.
The six borehole pumps were replaced by six 15kW Grundfos submersible pumps with Open S-tube impellers with the ability to handle large compressible solids. Each of the submersible pumps handles a flow rate of 15 l/s to 55l/s and at a maximum flow rate of 230 l/s four duty pumps will be utilized with two pumps as standby.
Some of the existing pipework was refurbished and the valves, reflux valves, pressure gauges and packings were replaced.
The raw river water is pumped through two strainers installed in parallel configuration. An-adjustable pre-selected pressure loss over each strainer initiates an automatic cleaning cycle new pipework with valves, automatic actuators and specials were installed to accommodate the filters.
Six new Grundfos CR type centrifugal pumps were installed, two 37kW pumps each capable of handling a flow rate of 15 l/s to 25 l/s and four 90kW pumps each capable of handling a flow rate of 25 l/s to more
than 60 l/s.
Refurbishment of the existing pipework and specials were done to accommodate the new centrifugal pumps.
The pump sets are controlled with Grundfos model CUE variable speed drives and Grundfos CU362 controllers.
The following civil and building works were also performed under this contract:
- Modifications to the electrical building to accommodate the new Motor Control Centre.
- Manufacture, fabricate and install galvanized steel pumphouse structure including steel single door, ventilation and louvres including roll-up door and electrical hoist, all on a cast concrete floor.
- Construction of strainer slab and thrust blocks.
- Re-construction of Stormwater channel.
- Reinstatement of stormwater system, unblocking scour valve and improvement of stormwater runoff.
- Construction of walkways, steps and new fence access gate.
- Construction of new concrete road.
Website: https://www.tricomafrica.co.za
