UKHP is a run of river hydropower project with an installed capacity of
150MW (consisting of two 75MW units) and It will produce 409GWh per year.
It has the following components:
- A dam located close to the town of Talawakelle
with a height of 35.5m and a crest length of 180m. It will have a gross
storage of 2.5 MCM with an effective capacity of 0.8 MCM with a surface
area of 0.25km2 (60 acres). Full supply level for the reservoir will
be 1,194 metres above mean sea level (msl), the minimum operating level
will be 1190m msl and the normal tail water level 703m msl.
- A headrace tunnel 4.5m/5+.2m in diameter
lined and unlined and 12.89km in length, running north from the dam
towards the Pundal Oya Falls before turning to the northwest towards
the existing Kotmale dam and reservoir. (The maximum gross head between
the reservoir and the powerhouse will be 491m).
- An upstream surge tank 12m in diameter and
98m high with a restricted opening, located on the crest of the power
- The penstock formed by an underground incline
shaft starting with a diameter of 4.5m and reducing to 1.45m. It will
be 793m in length, consisting of one lane of 745m and two lanes of 48m.
- An underground powerhouse located at Niyamgamdora,
(2km upstream of the confluence of Puna Oya and Kotmale Oya) with dimensions
of 66.3m L x 18.8m W x 36.5m H to house two units of 77,000kW turbines,
two vertical axis three phase 88,000kVA generators, two 3-phase, transformers
and a 220kV Gas Insulator Switchgear (GIS) substation.
- An outdoor switchyard, 36.5m wide and 130m
long, located at Niyamgamdora, to connect the Power House to a 220kV
double circuit transmission line.
- 220kV double circuit transmission line of
18km length to transmit power generated to existing Kotmale Substation
and the associated switch yard extensions.