Mariental floods unavoidable, maintains Minister Iyambo

FOR the first time since the Mariental floods more than two weeks ago, Minister of Agriculture, Water and Forestry, Dr Nickey Iyambo, yesterday commented on events at the town and said the floods could not have been prevented.

Speaking in the National Assembly, Iyambo defended NamWater’s decision to release water from the Hardap Dam in the manner that it did. He said that assessments done with hindsight, to determine whether it could have acted more proactively by releasing water earlier, showed that this would still have flooded the town.Iyambo said had NamWater known a day earlier how much it would rain in the catchment area, and released 2 000 cubic metres of water per second from 10h00 on February 24, the dam level would still have peaked at 110 per cent.”By now we also know that such [a] discharge rate would in any case have resulted in extensive flooding of the entire western part of town,” said Iyambo.The Minister said he was satisfied that sufficient warning was given by the Department of Water Affairs that the petrol station west of the tar road would flood.He said NamWater officials had also warned the pig farm outside Mariental that they were at risk because they were situated within the flood plain of the Fish River.Iyambo said the Emergency Management Committee and Flood Management Committee were informed at 08h00 on Friday that the sluice gates would be opened two hours later.”This gave them approximately four to five hours before the water reached the town,” said Iyambo.Iyambo’s statement was prompted by a motion tabled last week by the Republican Party’s Henk Mudge: that Parliament should discuss the reasons for the flood and that Government should take steps to prevent future flooding.Mudge said the riverbed had to be cleared of obstructions because its capacity had diminished dramatically from approximately 2 000 cubic metres per second to only 450 cubic metres per second.Mudge contended that the early warning and monitoring systems were inadequate and contributed to the flooding.Iyambo, and Swapo MPs who took the floor after him, all discouraged criticism of the water utility NamWater and Government and said the focus should instead be on restoring the town and assisting the affected.”My reason for making this statement is not to point a finger at anybody but rather to point out why such a flood could not have been prevented under the conditions and circumstances [that] prevailed at the time and to inform honourable members of the National Assembly and members of the public,” said Iyambo.He said that even before the dam was built in 1961, the then Director of Works advised the Townships Board not to develop the area west of the railway line because it would be prone to flooding.Flooding in 1923, 1934, 1949 and 1950 occurred with such intensity (1 990 cubic metres per second), that it flooded the town up to window height on First Street.”I am not mentioning these things as an effort to blame those who approved or constructed buildings and houses in an area which should not have been inhabited.It is rather to reflect on what happened,” said Iyambo.Iyambo further defended NamWater’s decision to maintain the level of the Hardap Dam at 80 per cent of capacity, saying it was to ensure an adequate supply of irrigation water for at least two years, in the event of no rain.”Maintaining the dam at a lower level will not help if floods like the ones in 2000 or 2006 occur,” said Iyambo.”Dam safety can never be compromised, because the dam is irreplaceable and the town of Mariental will be wiped off the map if the dam breaks.”During the recent flood at Mariental, 500 million cubic metres of water was released from the dam, an amount equivalent to three-quarters of the dam’s capacity, over a period of three days.”This gives one an idea of the volumes of water which had to be managed and the impossibility under the circumstances to prevent the extensive and much-regretted flooding of Mariental,” said Iyambo.He said that assessments done with hindsight, to determine whether it could have acted more proactively by releasing water earlier, showed that this would still have flooded the town.Iyambo said had NamWater known a day earlier how much it would rain in the catchment area, and released 2 000 cubic metres of water per second from 10h00 on February 24, the dam level would still have peaked at 110 per cent.”By now we also know that such [a] discharge rate would in any case have resulted in extensive flooding of the entire western part of town,” said Iyambo.The Minister said he was satisfied that sufficient warning was given by the Department of Water Affairs that the petrol station west of the tar road would flood.He said NamWater officials had also warned the pig farm outside Mariental that they were at risk because they were situated within the flood plain of the Fish River.Iyambo said the Emergency Management Committee and Flood Management Committee were informed at 08h00 on Friday that the sluice gates would be opened two hours later.”This gave them approximately four to five hours before the water reached the town,” said Iyambo.Iyambo’s statement was prompted by a motion tabled last week by the Republican Party’s Henk Mudge: that Parliament should discuss the reasons for the flood and that Government should take steps to prevent future flooding.Mudge said the riverbed had to be cleared of obstructions because its capacity had diminished dramatically from approximately 2 000 cubic metres per second to only 450 cubic metres per second.Mudge contended that the early warning and monitoring systems were inadequate and contributed to the flooding.Iyambo, and Swapo MPs who took the floor after him, all discouraged criticism of the water utility NamWater and Government and said the focus should instead be on restoring the town and assisting the affected.”My reason for making this statement is not to point a finger at anybody but rather to point out why such a flood could not have been prevented under the conditions and circumstances [that] prevailed at the time and to inform honourable members of the National Assembly and members of the public,” said Iyambo.He said that even before the dam was built in 1961, the then Director of Works advised the Townships Board not to develop the area west of the railway line because it would be prone to flooding.Flooding in 1923, 1934, 1949 and 1950 occurred with such intensity (1 990 cubic metres per second), that it flooded the town up to window height on First Street.”I am not mentioning these things as an effort to blame those who approved or constructed buildings and houses in an area which should not have been inhabited.It is rather to reflect on what happened,” said Iyambo.Iyambo further defended NamWater’s decision to maintain the level of the Hardap Dam at 80 per cent of capacity, saying it was to ensure an adequate supply of irrigation water for at least two years, in the event of no rain.”Maintaining the dam at a lower level will not help if floods like the ones in 2000 or 2006 occur,” said Iyambo.”Dam safety can never be compromised, because the dam is irreplaceable and the town of Mariental will be wiped off the map if the dam breaks.”During the recent flood at Mariental, 500 million cubic metres of water was released from the dam, an amount equivalent to three-quarters of the dam’s capacity, over a period of three days.”This gives one an idea of the volumes of water which had to be managed and the impossibility under the circumstances to prevent the extensive and much-regretted flooding of Mariental,” said Iyambo.