Flood Management in Tungabhadra Reservoir- Case for Integrated Operation of Reservoirs

1 TUNGABHADRA PROJECT: Inter State

, &  Managed by Tungabhadra Board under MoWR, RD & GR, Govt. of Outline of Presentation

 Project Locations

 Salient features of Project & Tungabhadra

Flood forecast System in Tungabhadra

 Reservoir/ Gate Operation Schedule of

Historical Spillway Discharge data of TB Dam

Important Places affected during floods

Inflows Recorded at TB Dam Vs Forecast given by CWC

Need for integrated reservoir operations

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SINGATALUR Distance between two PROJECT is about 80Km Salient Features

SINGATALUR PROJECT  Storage Capacity =2.6TMC (Live) FRL = (+)509.00m Crest Level = (+)501.00m Design Flood = 5.2 Lakh Cusecs Power Generation =18MW (mini Hydel)

TUNGABHADRA PROJECT  Storage Capacity =100.8TMC (Live) FRL = (+)497.74m RL Crest Level = (+)491.64m Design Flood = 6.5 Lakh Cusecs Max. Observed Flood =3.69 Lakh Cusec ( Nov1992)

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EXISTING FLOOD FORECASTING STATIONS IN TUNGABHADRA

Forecast Criteria / Type of Data S No Forecast Station State River Base Stations Threshold Limit used INFLOW FORECAST STATIONS WL,Q.RF 1 Upper Tunga Karnataka Krishna 425 cumec MIKE 11 Model WL,Q.RF

WL,Q.RF 425 cumec MIKE 11 Model WL,Q.RF 2 Bhadra Project Karnataka Tungabhadra WL,RF

Harlahalli WL,Q.RF Tungabhadra 3 Karnataka Tungabhadra 425 cumec Marol WL,Q.RF Dam

Sunkesula 500 cumec WL,Q.RF 4 Andhra Pradesh Tungabhadra Barrage

Warning Danger LEVEL FORECAST STATIONS Level (m) Level (m) Andhra Pradesh Tungabhadra Oollenur WL,Q.RF 1 Mantralayam 310.00 312.00 T Ramapuram WL,Q.RF

Mantralayam WL,Q.RF Andhra Pradesh Tungabhadra (Monitoring) 2 Town 274.00 276.00 WL,Q.RF BASE STATIONS IN TUNGABHADRA DAM

Base Station Stream Forecast Travel time Distance (km) Peak velocity station (hrs) (m/sec) Harlahalli Tungabhadra TB Dam 12 to 27 109 2.52 Marol TB Dam 12 to 27 106 2.45 FLOOD OPERATION SCHEDULE OF TUNGABHADRA RESERVOIR

10 TUNGABHADRA DAM : Maximum Spillway Discharge 1960-2018 ( 59 years data)

400,000

350,000 Discharge in Cusec 300,000

250,000

200,000

150,000 Discharge, Cusec Discharge,

100,000

50,000

0 1960 1962 1964 1966 1968 1970 1972 1974 1976 1978 1980 1982 1984 1986 1988 1990 1992 1994 1996 1998 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 Year

11 VIEW OF TUNGABHADRA DAM IN AUGUEST 2018

12 VIEW OF TUNGABHADRA DAM IN AUGUEST 2018

13 TUNGABHADRA DAM IN NIGHT VIEW

14 IMPORTANT PLACES AFFECTED DURING FLOODS ALONG

, a UNESCO World Heritage Site is located 40 Kms downstream of Dam.

Navabrindavan, near Hampi, is of importance to the followers of the saint Sri

Raghavendra. The Brindavan (sacred tomb) of the Nine saint is located 20 Kms downstream of Dam in a small island formed by Tungabadra, east of the

Anegondi village.

2009 historical floods

 Mantralaya is one of important pilgrimage center with Brindavan of Sri

Raghavendra Swamy Temple ( 17 Century saint) which is located 150km downstream of TB Dam.

Kurnool town is located 180km downstream of TB dam.

15 Flooding in Hampi during 2018 (above 200000 Cusec)

Purandhara dasa mandapa

kodandarama temple Hampi 16 Inflows/Outflow Recorded at TB Dam Vs Forecast Issued by CWC

During the water year 2018-19 the Tungabhadra dam is filled early i.e. in the month of July. On 19th of July the spill way gates are opened as per flood operation schedule. On 17th Aug 2018—2,20,000 cusec (Max. discharge of 2018) was released

17 Inflows Recorded at TB Dam Vs Forecast given by CWC

200000

150000 Recorded at TB DAM

Forecast Issued by CWC

100000

50000 INFLOW in Cusec in INFLOW

0 14.06.2018 16.06.2018 18.06.2018 02.07.2018 11.07.2018 13.07.2018 15.07.2018 17.07.2018 19.07.2018 21.07.2018 23.07.2018 25.07.2018 27.07.2018 29.07.2018 31.07.2018 02.08.2018 04.08.2018 06.08.2018 08.08.2018 10.08.2018 12.08.2018 15.08.2018 17.08.2018 19.08.2018 21.08.2018 23.08.2018 25.08.2018 27.08.2018 29.08.2018 31.08.2018 02.09.2018 04.09.2018 22.10.2018

18 A case for integrated Operations of Reservoirs Singataluru project & Tungabhadra

By Comparing the above inflow forecast of CWC Gauge & inflow realized at TB Dam

 The average variation is 13% ( Permissible accuracy limits is 20 %).

 Variation is more during High flood period.

 Variation is low during receding time of flood at TB Dam.

 The above variation is due to independent operation of Singataluru Project (Power house) during flood season.

Singataluru Project authorities suddenly release during floods without intimation to downstream TB Dam project & sudden closing the gates during receding time of flood.

This is causing problem to correctly assess inflow to the Tungabhadra Dam and accordingly operate spillway gates to release the flood. 19 A case for integrated Operations of Reservoirs Singataluru project & Tungabhadra

Incident of more spillway releases than inflow on 1st September 2018 –TB Dam.

CWC is proposing inflow forecast station at Singatalur project from monsoon 2019.

This is intune with the CWC proposals for creations flood crisis management teams (FCMT) for set of reservoirs in sub-basin/basins of the country for integrated operation of reservoirs so that flood is mitigated.

20 THANK YOU