Flood bypass measures

The huge, devastating floods that tore through Somerset West in August and November 2013, when the Lourens River burst its banks, galvanised the City of Cape Town to implement flood mitigation measures.

A study conducted by the Institute of Water Engineering at the University of Stellenbosch, made key long-term recommendations which included a combination of a flood bypass canal, with floodplain walls or berms, upstream of the main urban area, with berms in critical locations along the main river channel.

The work has progressed in phases since then, and phase 1h is currently underway, according to City of Cape Town mayoral committee member for transport, Brett Herron.

“This is part of an ongoing project aimed at mitigating the risk of flooding caused by the Lourens River during heavy downpours. The project was initiated as far back as 2001 and is being implemented in a phased manner, subject to the availability of funding,” Mr Herron told Bolander.

According to Mr Herron, the work being done as part of the current phase covers the section of the Lourens River from Main Road, Somerset West to more or less Hathersage Farm and includes such work as the improvement of the underground stormwater system in Voortrekker Street; the construction of a stormwater retention facility in Somerset Street; and the construction of flood control walls on Penny and Meadow lanes.

It also includes the improvement of the underground stormwater management system serving Gordon Road; the widening of the river channel in order to increase its capacity to 120 cubic metres per second; river bank stabilisation by means of gabion walls, reno mattresses and retaining walls; the construction of levees and earth berms to retain the flow in the river channel, and rehabilitation of the disturbed areas in the river channel by means of landscaping using plants prevalent in the river.

Mr Herron added that the work being done includes the rehabilitation of the historic bridge just off Main Road adjacent to the Old Bridge Tavern which was recently completed.

“The tender was awarded to a contractor for an estimated contract value of R37 803 000. The work commended on June 13 last year and completion is anticipated by August 14, 2018, weather permitting,” Mr Herron said.

Bolander spoke to sub-council 8 chairperson, and Ward 84 councillor, Stuart Pringle, about the current project.

“I am very pleased with the work being done by the City in terms of the Lourens River Flood Alleviation Measures, which were proposed and discussed as long ago as the early 1980s, but which previous administrations didn’t have the financial means to attempt.

“Mitigation measures against flood damage are very important as the number of developments, particularly close to the Lourens River, have increased dramatically over the past few decades and protecting residents and their property is a primary function of any government,” he said.

“I am also very pleased that this project is being used to upgrade our heritage, such as the Old Bridge, which is an important monument to Somerset West’s history and has long been in need of an upgrade.

“This flood alleviation work indicates that we are benefiting from major capital work by the municipality and I’m grateful to Mr Herron for being such a strong advocate for these projects,” said Mr Pringle.