Lingza - Ministry of Power

• Study of existing infrastructure.
• Cost benefit and economic evaluation.
1.3 RESULTS OF STUDIES AND INVESTIGATIONS
1.3.1 Geology
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Preliminary Feasibility Report
Lingza HE Project (3 x 40 MW)
The preliminary geological survey of the locations of all the structures on the ground was
carried out after site visits. The site-specific geological data were got collected and
utilized in the design of various components of the project. The geological survey of the
near by area was also carried out to co-relate the geology of the project area. The dam
location has been fixed after observing the rock exposures on both the banks and in the
riverbed.
1.3.2 Hydrology
The river Ringpi drains a catchment area of about 198sq.km at the proposed dam site.
The water availability for the project has been considered on the basis of 10-daily
discharge series at Lachen for the period from 1976-1997. The water availability at the
Lingza dam site has been derived from the above data on the basis of catchment area
proportion and applying an overall reduction factor of 0.22. The computed inflow series
works out has been utilized for Power Potential Studies. The design flood has been
assessed as 940cumecs.
1.3.3 Power Potential Studies
The computed inflow series for 21 years viz June 1976 to May 97 has been considered in
the assessment of a power benefits from the project. As per GOI notification for tariff the
year 1976-77 corresponds to 90% dependable year. An installation of 120MW
comprising 3 generating units of 40MW has been proposed. The energy availability from
the project in a 90%dependable and an average year has been summarized below:
Annual Energy Generatio n
Annual Energy Generation (GWh) 477.51