REHABILITATION OF VERULAM AND LA MERCY PUMP STATION

Located in Verulam, 24 km north of Durban, KwaZulu-Natal, the Hazelmere WTW treats an average of 72 Mℓ/day of water, which it supplies to eThekwini Metro, iLembe District Municipality and Siza Water.

The Verulam and La Mercy Pump Station is part of the Hazelmere Water Treatment Works (WTW) system and has seven pumps –four pumps dedicated to the La Mercy area and three for the Verulam area.

Water from the Verulam side of the pump station is pumped to a holding tank at Grange that distributes to surrounding areas. The La Mercy side of the pump station also acts as a backup to the Avondale Pump Station that supplies Ballito. Water from the Verulam side services a population of 70 000 people.

Scope of works

In order to meet all pumping requirements to iLembe District Municipality, APE Pumps was appointed by Umgeni Water to replace all damaged electrical, mechanical and instrumentation equipment, as well as attend to supporting infrastructure and facilities at the Verulam and La Mercy Pump Station.

The scope of works included:

• repair of faulty variable-speed drive (VSD) equipment for pump set 4

• repair of faulty La Mercy pump set 2 and 3

• refurbishment of faulty Verulam pump set 1 and 2

• supply of new La Mercy pump set 1

• supply of new Verulam pump set 3

• replacement of motors (La Mercy 1, 2 and 3, as well as Verulam 1 and 2)

• replacement of damaged delivery valves (La Mercy 1, 2 and 3) and (Verulam 1 and 2)

• replacement of blower room equipment’s pump and motor

• supply of drainage pump and motor control for flood prevention

• roof repairs to La Mercy Pump Station

• commissioning of all pump sets at La Mercy and Verulam Pump Station.

With the aim to pump 30 Mℓ/day of water from the Verulam pumping station to the Grange reservoir, pump set 3 was added to the two existing pumps at Verulam. Suction valves and piping were added, along with non-return valves, gate valves and actuators.

“Pump set 3 is bigger (500 kW) than the two other ones (185 kW) due to a new bulk water pipeline being built for the Grange area. Since we are ahead of the schedule and the pipeline is not complete, we have had to throttle the flow and reduce the pressure for the old line,” explains Peter Robinson, director at APE Pumps.

The pump station was also fitted with a Scada system, enabling it to be remotely operated and monitored from the Hazelmere WTW Office Block.

All pumps at the Verulam and La Mercy Pump Station are APE vertical turbine pumps. Vertical turbine pumps are centrifugal pumps that are designed to operate in a vertical orientation, with the impeller located below the water level. APE Pumps offers a range of vertical turbine pumps designed to meet various flow and head requirements. These pumps are known for their high efficiency, durability and long service life. They are especially well suited for installation within smaller footprints like pump stations, saving on construction costs, or where space is too restricted for a multistage pump setup. Another major advantage of vertical pump systems is that they are relatively simple to strip and maintain.

The company worked with OBS Mechanical Electrical Turnkey Projects – a Level 1 BBBEE company – for transformation purposes. OBS has already partnered with APE Pumps on a number of Umgeni Water projects (including the installation of pump 4 at the Verulam pumping station). The company has expertise in many areas of engineering, including water movement and treatment.

Pump 4 at La Mercy

“APE Pumps has previously worked on the pump station. Two years ago,

APE Pumps replaced a split-case pump with a new vertical turbine pump (APE

18 HC) – complete with piping, auxiliaries, valves, instrumentation and a motor. The pump was specifically designed to fit into the footprint of the old one. It was fitted with a 650 kW VSD, where, instead of running two pumps in line, only one pump would be used. This is because pump 4 can deliver in excess of what the two pumps could currently achieve,” states Robinson.

After problems were experienced with the switchgear and induction motors, APE Pumps was further tasked with replacing the medium-voltage switchgear from the 6.6 kV 2 off 1.6 MVA 11/66 kV transformer. Six 6.6 kV 500 kW soft starters were installed – an extra one was included for future expansion plans.

“The APE Projects Division has managed and implemented the design, installation and commissioning of VSDs switchgear, motors, transformers, valves, distribution boards, cabling, pipework and pipelines, as well as, of course, pumps for both projects. This division takes responsibility for mechanical, electrical and civil works, and is currently graded as an 8 ME contractor by the Construction Industry Development Board. APE’s pumps are only guaranteed if the project team completes the installation,” adds Robinson. He states that APE Pumps is a proudly South African company that is committed to and invested in South Africa. “Our products are 100% locally cast by South African foundries using local materials. That has major advantages for our clients because we are not reliant on imports and can design and fabricate pump systems within remarkably short turnaround periods. If well maintained, our pumps will last a lifetime – across Southern Africa, there are hundreds of working examples.”