Polgolla Dam with all spillways open
|Location||Polgolla, Central Province|
|Opening date||July 1976|
|Dam and spillways|
|Type of dam||Barrage|
|Height (foundation)||14.6 m (48 ft)|
|Length||144 m (472 ft)|
|Total capacity||4,100,000 m3 (140,000,000 cu ft)|
|Active capacity||2,100,000 m3 (74,000,000 cu ft)|
|Maximum length||1,200 m (3,900 ft)|
|Maximum width||170 m (560 ft)|
|Ukuwela Power Station|
|Operator(s)||Ceylon Electricity Board|
|Turbines||2 × 20 MW|
|Installed capacity||40 MW|
The Polgolla Barrage (also erroneously known as the Polgolla Dam), is a barrage built across the Mahaweli River at Polgolla, in the Central Province of Sri Lanka. The barrage is used to increase the volume of water, for transfer to the hydroelectric power station located 8 km (5 mi) north, via penstock.
Polgolla Reservoir Waterdrome operates a short distance upstream on the lake created by the barrage.
Water from the Polgolla Reservoir is transferred to the Ukuwela Power Station at 8 km (5 mi) long underground penstock. Water from the reservoir is transferred to the power station at a rate of 2,000 cu ft/s (57 m3/s)., near Ukuwela, via a
The power station at Ukuwela consists of two 20 MW hydroelectric generators, totalling the plant capacity to 40 MW . Both units were commissioned in July 1976. Water from the power station is discharged into the Amban River, a major tributary to the Mahaweli River, which then connects back to the Mahaweli River at a distance of approximately 140 km (87 mi) downstream of the Polgolla Barrage.
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