Darlington Dam

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Darlington Dam
Darlington Dam (2014)
Darlington Dam (2014)
Tributaries: Sundays River
Drain: Sundays River
Major cities nearby: Kirkwood
Darlington Dam (Eastern Cape)
Darlington Dam
Coordinates 33 ° 8 '53 "  S , 25 ° 7' 59"  E Coordinates: 33 ° 8 '53 "  S , 25 ° 7' 59"  E
Data on the structure
Lock type: Gravity dam
Construction time: 1916-1922
Height above foundation level : 48 m
Crown length: 418 m
Data on the reservoir
Reservoir length 14.6 kmdep1
Reservoir width 15.1 kmdep1
Storage space 0.209 million m³
Total storage space : 252 million m³

The Darlington Dam (formerly Lake Mentz ) is a reservoir in the South African province of Eastern Cape , near the city of Kirkwood . The Sundays River was dammed in 1922 to irrigate the river valley for agricultural use. Today the water also comes from the Gariep Dam . The lake is 15 kilometers wide and 14 kilometers long.

The reservoir was named after Darlington , which was flooded when it was dammed. Until 1995 the lake was called Lake Mentz . In 2000 the lake became part of the Addo Elephant National Park .

history

Early irrigation projects

James Somers Kirkwood, an auctioneer from Port Elizabeth, started thinking about building an irrigation system . He visited the Sundays River Valley in 1877. Since he liked the area so much, he bought a farm and settled there. After buying more land - in 1883 he owned 21 farms totaling 29,985 acres - Kirkwood set up the Sundays River Land and Irrigation Company to carry out larger projects for irrigation in the area. However, Kirkwood went bankrupt as he could not find investors due to an economic depression.

In 1887 the Guardian Assurance and Trust Company took over Kirkwood's property from Port Elizabeth and sold it to Strathsomers Estate Company in 1903 . 1909 examined Strathsomers Estate in Korhaan's Drift the grounds on which the irrigation project was planned. The project included the construction of a diversion weir . However, the project was postponed due to a process. Strathsomers Estates' right to use water was challenged, but ultimately won. In 1911 construction work began on the Koorhan's Drift Weir. The weir was completed in November of the following year. With the help of the weir over 4000 hectares of land could be irrigated, making it the largest irrigation system in South Africa at the time.

Planning and construction

In 1913, the well-known author and businessman Percy FitzPatrick visited the facility. Shortly thereafter, he founded the Cape Sundays River Settlements Company because he needed a permanent water supply for the citrus fruit he was planning in the area. The drought in the years 1913 to 1915 made many farmers look for new sources of income and also made it clear that water had to be stored permanently. A flood in 1916 made this clear, as large amounts of water could not be used for irrigation. As a result, the previously competing irrigation companies joined forces and presented the government with a plan for a reservoir to store water. After the government approved the project, the Sundays River Irrigation Board was established, whose sole responsibility was to build the reservoir. The state provided a loan for the construction of Lake Mentz , as the lake was called soon after the Minister of Lands Hendrik Mentz. The loan was to be repaid through an irrigation canal usage fee, which should be collected by the irrigation board.

The preparatory work had already been completed by mid-1917 and in March 1918 the Sundays River Irrigation Board took over the management of the work from the Department of Irrigation to build the dam.

The gravity dam made of concrete should be about 300 meters long and 25 meters high. Six hydraulically controlled locks were supposed to regulate the flow. When filled, the reservoir held over 140 million cubic meters of water.

The construction of the dam turned out to be very difficult. One difficulty was that the nearest train station was 40 kilometers away. Before construction began, around 30 kilometers of road had to be built through mountainous land. A telegraph line was also set up. This and the road were completed in 1918. Since the transport of the building materials was carried out with the help of donkeys and there was hardly any food for the animals in the mountainous landscape, intermediate stations had to be set up every 13 kilometers to provide the donkeys with drinking water. The feed always had to be carried along. Up to 500 donkeys and 30 wagons were used. 16 donkeys each pulled a three-ton wagon. On average, the 30-kilometer journey (there and back) was covered ten times a month. Another problem was the First World War , which was just taking place. For one thing, it was difficult to recruit workers. On the other hand, it was almost impossible to get suitable equipment and machines. That is why outdated and used equipment often had to be bought at inflated prices. The former soldiers hired for the construction site created new problems. They weren't used to this way of working. In addition, many suffered from relapses of malaria that they contracted during the war. Most of the workers died as a result of the flu epidemic and the plague . A subsequent drought reduced the water supplies that were needed for the workers and for building. These delays meant that the dam could not be completed until 1922.

Later changes

Although some large locks were built for leaching purposes, there were still major problems with silting up from the widespread soil erosion in the Eastern Cape . This meant that the dam wall had to be increased by 1.5 meters in 1935. In 1951 the dam wall was raised again by 5.8 meters. Then by 1962 70 kilometers of the main sewer and 155 kilometers of the distribution sewers were lined with concrete. In 1975 the Orange-Fish River Tunnel was inaugurated, through which water from the Orange River has been flowing into the dam ever since .

Web links

literature

Individual evidence

  1. ↑ Darlington (reservoir) ( English ). Retrieved January 28, 2010.