The Montagu area has experienced at least 10 major floods since the town’s establishment in the early 1850s.
The first recorded flood was in 1867, when the Keisie River burst its banks and swept away vineyards below the town. Twelve people died in this event. This flood left the kloof impassable for weeks, which prompted the Cape government to commission the construction of the pass.
The most severe flood to affect the Montagu area occurred on January 25, 1981, a date remembered in South Africa for one of the worst natural disasters in the country’s history. Torrential rain across parts of the Western Cape caused widespread flooding. In Laingsburg, 100km northeast of Montagu, a major part of the town was swept away and more than 100 people lost their lives.
In Montagu a flood of water and debris tumbled down the Keisie River, obliterating parts of the Montagu hot springs before inundating lower parts of the town. Thirteen people lost their lives and millions of Rands worth of property was damaged. The ferocity of the flood was such that bodies were swept through Cogmans Kloof and recovered downstream of Ashton. The road through the gorge was impassable. Left without electricity, drinking water and telephone connections, Montagu was effectively cut off from the rest of the country for days.
Another disastrous flood struck on March 24, 2003. Between 200mm and 300mm of rain had fallen over the Keisie and Kingna rivers’ catchment areas in the preceding 18 hours. Both rivers broke their banks, and the inundation of a large part of the lower town and adjoining agricultural lands and infrastructure caused significant damage. This was so severe that Cogmans Kloof was closed for 16 days. Montagu was declared a disaster area and helicopters ferried emergency supplies to the town.
The most recent flood occurred on November 12, 2008. 120mm of rain fell on the town over three days, while the Koo Valley to the north‑west received between 360mm and 500mm. This water was channeled down the Keisie River and through the town, causing extensive damage and sweeping away the footbridge linking the suburb of Montagu West to the rest of the town. On this occasion, the town was cut off for three days.
The severity of flooding in the Montagu area is due to a variety of factors, but mainly to geography and weather.
The town itself is located just upstream of the confluence of the Kingna and Keisie rivers on the northern side of Cogmans Kloof. When a cut‑off low pressure weather system forms, it results in very heavy rainfall across the normally dry Klein Karoo and adjoining mountain ranges. The run‑off water is channeled into the catchments of these rivers and turns them into raging torrents, encircling the town