Chapter – 5 Hydrology and Water Assessment

5.0 General

The Par-Tapi-Narmada Link Project involves Par, Auranga, Ambica and Purna river basins of South Gujarat and neighboring Maharashtra State. The Hydrological studies of this project comprising Par, Auranga, Ambica and Purna river basins with Jheri, Paikhed, Chasmandva, Chikkar, Dabdar and Kelwan dam sites were carried out by Hydrological Studies Organization, Central Water Commission, New Delhi. The hydrological studies of the Par-Tapi-Narmada link had been compiled in three volumes by Central Water Commission; Volume– I: Water availability studies; Volume– II: Design flood and diversion flood (in two parts); Volume– III: Sedimentation studies and were appended in “Volume– IV: of DPR i.e Appendices – Hydrology and Water Assessment” of the DPR of the link project prepared by NWDA in August, 2015. Brief details of the studies werealso furnished in “Volume-I: Main Report”of the DPR (August-2015) under Chapter-5 - Hydrology and Water Assessment.

Since the link canal demands and diversion of surplus yields available for diversion at the above proposed reservoirs are unchanged, no separate Hydrological and Water Assessment studies have been carried out. Brief details of the studies are furnished below.

5.1 General Climate and Hydrology

The climate of the Par-Tapi-Narmada link project area is moderate except during the months of April and May. Summer is hot and winter is generally cold. The year may be divided into four seasons, the cold season from Dec to Feb followed by the hot season from March to May and the south-west monsoon season from June to Sept followed by the post- monsoon season from Oct to Nov.

As per the Hydrological studies, the Par river at proposed Jheri dam site; Nar river (tributary of Par river) at proposed Paikhed dam site; Tan river (Tributary of Auranga river) at proposed Chasmandva dam; Ambica river at proposed Chikkar dam site; Khapri river (tributary of Ambica river) 147 at proposed Dabdar dam site; and Purna river at proposed Kelwan dam site have been found water surplus at 75% dependability. As such after meeting in-basin requirements (by 2050 AD) of all the above four river basins up to the proposed dam sites and downstream commitments / requirements, surplus water of 1210 MCM has been proposed for diversion to utilize en- route of link canal in the tribal areas lying rightside of link canal,periphery of proposed reservoirs, tribal areas lying right side of Narmada Main Canal (in Chhota Udepur and Panchamahals Districts) by lift;to takeover the command areas of the projects viz., i) Khuntali, ii) Ugta, iii) Sidhumber, iv) Khata Amba and v) Zankhari proposed by Government of Gujarat to supply drinking water to all villages of Dangs District and villages of Kaprada and Dharampur talukas of Valsad District; to fill all possible tanks in the benefitted areas and in water short Saurashtra region of Gujarat by Substitution. The Par-Tapi-Narmada link will also take over the part command area of existing Miyagam Branch Canal of Narmada Canal System and the Narmada waters so saved in Sardar Sarovar dam will be utilized in Chhota Udepur and Panchamahal Districts and Saurashtra region for providing irrigation facilities and drinking water by substitution. The schematic Diagram of the Par-Tapi-NarmLink Project is at Fig. 5.1.

148 5.2 General Information about Regions The Par-Tapi-Narmada link involves Par, Auranga, Ambica and Purna river basins of South Gujarat and neighboring Maharashtra. All these four river basins have the same hydro meteorological characteristics. Most of the 149 rainfall is received during the South-West monsoon period, from June to Sept. The average annual rainfall in the Par, Auranga, Ambica and Purna river basins is 2180 mm, 2055 mm, 1830 mm and 1472 mm respectively. Two meteorological observatories at Surat and Vadodara maintained by India Meteorological Department (IMD) located adjacent to the project area have been used to characterize the climatic conditions of the project area. The average maximum and minimum temperatures recorded are 39.9 °C and 13.2 °C respectively. The monthly mean relative humidity data of the project area indicates the maximum and minimum values of humidity as 94% (August) and 44% (April) during monsoon and summer seasons respectively. The maximum and minimum wind velocities observed are 13.3 km/hr and 2.2 km/hr respectively. The maximum cloud cover is observed during the months of July and August whereas the minimum cloud cover is observed during months of Jan and Feb. There is no pan-evapometer installed in the project area. The mean monthly average evapotranspiration computed for Surat IMD observatory varies from 99.2 (Dec) to 202.0 mm (May), whereas the same at Vadodara IMD observatory varies from 92.9 mm (Dec) to 246.4 mm (May).

5.3 Specific Information 5.3.1 Drainage Basins a) Par Basin

The Par River is one of the important west flowing rivers in the region, north of Mumbai and south of the Tapi river. The river originates from the Sahyadri hill ranges near village Gogul of Surgana taluka in Nasik district of Maharashtra at an elevation of about 1100 m above mean sea level. The total length of the river from its origin to its outfall into Arabian Sea is 131 km.

The river basin lies between 20°16' – 20°35' N latitudes and 72°54' – 73°44' E longitudes. The total catchment area of the river is 1664 km2, out of which 773 km2 lies in Nasik district of Maharashtra and the remaining 891 km2 in Valsad district of Gujarat. It is bounded by western Ghat ridge separating west flowing rivers and Godavari in east, the ridge separating Kolak and Damanganga rivers in south, Arabian Sea in west and the ridge separating Par and Auranga rivers on north. The important tributaries of Par river are Aroti, Nar, Bhimtas, Vajri and Keng.

150 b) Auranga Basin

The Auranga is another important west flowing rivers in the South Gujarat region. The river is known as Auranga after the confluence of its two tributaries the Man and the Tan. Both tributaries originate in the Sahyadri hill ranges in the Nasik district of Maharashtra. The river traverses a distance of about 30 km from confluence of the tributaries before draining into the Arabian Sea. The Auranga river basin lies between 20° 30' to 20° 42' N latitudes, and 72°53' to 73°37' E longitudes. The Auranga basin extends over an area of 787 km2, out of which 150 km2 is in Maharashtra State and 637 km2 is in Gujarat. The effective drainage area of the basin in Gujarat State is 598 km2 since 39 km2 area near the mouth is low-lying, marshy and cannot be beneficially utilized. The basin is bounded by ridge separating Auranga and Par rivers in south and east, Arabian Sea in west and the ridge separating Auranga and Ambica rivers in north. Important tributaries of Auranga River are Man and Tan. c) Ambica Basin

The Ambica River is also a west flowing river of South Gujarat region located north of Auranga basin. The catchment area of Ambica basin is lying in Gujarat and Maharashtra. The Ambica River originates in the Sahyadri hill ranges near village Kotambi of Surgana taluka in Nasik district of Maharashtra at an elevation of about 1050 m above mean sea level. The total length of the river from its origin to its outfall into Arabian Sea is 164 km. The river basin lies between 20°31' – 20°57' N latitudes and 72°48' – 73°52' E longitudes. The total catchment area of the basin is 2830 km2, of which 102 km2 lies in Maharashtra and the remaining 2728 km2 in Gujarat. The catchment area of the basin in Gujarat is 2583 km2, since 145 km2 area near mouth is low lying, marshy and cannot be beneficially utilized. Ambica basin is bounded by Western Ghats separating Ambica and Tapi rivers in east, the ridge separating Auranga and Par rivers in south, Arabian Sea in west and the ridge separating Ambica and Purna rivers on north. Important tributaries of Ambica River are Khapri, Olan, Kaveri and Kharera. d) Purna Basin

The river Purna, a west flowing river, rises in the Sahyadri hill ranges of the Western Ghats at an elevation of about 1300 m in the Ahwa taluka of

151 Dangs district in Gujarat and after traversing a distance of 180 km, it outfalls into the Arabian sea. The level of the river bed drops steeply from 1300 m at source to about 115 m at the dam site as the river in this reach passes through hilly area covered with dense forest and patches of cultivated land. The Purna basin lies between 20°44' – 21°06' N latitudes and 72°44' – 73°58' E longitudes. The total drainage area of the basin is 2435 km2, out of which 58 km2 lies in Maharashtra and 2377 km2 lies in Gujarat. The effective drainage area of the river is 2193 km2 since 242 km2 near the mouth is low-lying and cannot be beneficially utilized. The Purna basin is bounded by Western Ghats separating Purna and Tapi rivers in east, the ridge separating Purna and Ambica rivers in south, Arabian sea in west and the ridge separating Purna and Mindhola on north. Important tributaries are Girra river, Zankhari river and Damas khadi.

5.3.2 Command Area as per the Revised Irrigation Planning

As per the revised planning Par-Tapi-Narmada link project will provide irrigation to 59920 ha new areas in the en-route of main canal; 1270 ha new area in the en-route of Dabdar and Kelwan feeder pipelines; and take over the part command area of existing Miyagam Branch Canal of Narmada Canal System to an extent of 42368 ha. In addition to this areas as per the suggestion of Gujarat Government have been included.

In the Chief Engineers level meeting held on 11/11/2016, Chief Engineer (South Gujarat) has suggested to include command of five proposed projects namely Sidhumber Reservoir Project, Ugta Irrigation Project, Khuntali Irrigation Project, Zankari and Khata Amba irrigation project which are in the vicinity of Par-Tapi-Narmada link canal and also to provide irrigation facilities in the tribal area, enroute the link canal.

(i) Accordingly command area of these five projects are included in the DPR . Details of these projects are given below in Table - 5.1:

Table – 5.1 Details of Proposed projects of Government of Gujarat

Sr. Name of River Taluka District Culturable Annual Reservoir command Irrigation No benefitted benefitted area (ha) (ha)

1 Sidhumber Man river Dharampur Valsad 17441 17441 152 Chikhli Navsari

2 Ugta Par river Dharampur Valsad 4963 4963

3 Khuntali Dholdo / Par Dharmpur Valsad 3162 3162 river

4 Khata Amba Kaveri Vansada Navsari 2741 2741

5 Zankari Zankari river Songadhand Tapi 17254 17254 Vyara

Total 45561 45561

It can be seen from the above table that an Annual Irrigation of about 45561 ha can be provided through inclusion of the above projects as proposed by Government of Gujarat, for which the proposed command area lies on the left side of the PTN link canal. Government of Gujarat desired to explore the possibilities for providing maximum possible irrigation facilities to tribal area in the right side of the Par-Tapi-Narmada link canal.

(ii) Accordingly possible areas at four different locations enroute on Right side of the PTN link canal have also been identified as requested by Government of Gujarat for providing irrigation in tribal areas. Since these areas are located at a higher level than the P-T-N canal, the water can be provided for irrigation by lift involving from about 3.0 m to 70.0 m. These are described below :

(a) Area No.1 is located in Par-Tapi reach between RD 113.25 to 115.00 km (Besuniya) of link canal and average F.S.L. of P-T-N Link canal near this area is 117.70 m. Irrigation can be provided through lift in this area upto 3 m from P-T-N link canal. About 900 ha area can be covered in this reach in Vyara tehsil of Tapi district.

(b)Area No.2 is located in Par-Tapi reach between RD 141.440 to 153.400 km (in between Jhankhri river and Mindhola river) of link canal and average F.S.L. of 153 P-T-N link canal near this area is 111.0 m. Irrigation can be provided through lift upto 50 m to 70 m from P-T-N link canal. About 13100 ha area can be covered in this reach in Songadh tehsil of Tapi district.

(c) Area No.3 is located in Tapi-Narmada reach between RD 32.00 to 72.00 km of link canal and average F.S.L. of this area is 70.0 m. Irrigation can be provided through lift of about 50 m from P-T-N link canal. About 6500 ha area can be covered in this reach in Mandvi and Mangrol tehsil of Surat district.

(d) Area No.4 is located in Tapi-Narmada reach between RD 72.033 to 87.274 km (in between Ghanta River and Amravati River) of link canal and average F.S.L. of this area is 71.5 m. Irrigation can be provided through lift by about 50 m to 70 m from P-T-N link canal. About 15700 ha area can be covered in this reach in Valia tehsil of Bharuch district. The summary of above command area in the right side through lift is given in Table – 5.2 below:

Table –5.2

Additional irrigation in the tribal areas lying on the right side of Par-Tapi- Narmada Link Canal by lift

Sl. Name of CCA Annual Irrigation at Taluka / Command Area 100% intensity of District No. (ha) irrigation (ha) benefitted

1 Area-1 900 900 Vyara / Tapi

2 Area-2 13100 13100 Songadh / Tapi

3 Area-3 6500 6500 Mandvi and Mangrol / Surat

4 Area-4 15700 15700 Valia / Bharuch

Total 36200 36200

154 (iii) As suggested by Government of Gujarat, it is proposed to bring 12514 ha under irrigation in tribal dominant districts of Dang and Valsad of Gujarat and Nasik district of Maharashtra, directly by lift from proposed six reservoirs of the project.

(iv) Command in the tribal areas inChhota Udepur and Pamchmahal districts :

It is proposed to provide irrigation in 23750 ha predominantly tribal areas of Naswadi, Kavant, Sankheda, Jetpur Pavi, Chhota Udepur taluks of Chhota Udepur district through lift, directly from Narmada Main Canal on substitution basis.

It is also proposed to provide irrigation in 10592 ha predominantly tribal area of Halol, Ghogamba and Kalol talukas of Panchmahal district through lift, directly from Narmada Main Canal on substitution basis.

Details of benefits considering all the above suggestions and details of water Demand are summarized in Table-5.3:

Table – 5.3 Irrigation / Drinking water benefits and water Demand of Par-Tapi- Narmada Link Project

Sl. Reach / Feedar CCA (ha) Annual Annual Irrigation Utilisatio No. (ha) n in In Non- Total (MCM) Tribal Tribal areas

1 Enroute command 51173 10017 61190 61190 382

2 Project proposed 40631 4930 45561 45561 285 by Government of Gujarat on the left side of link canal

3 Tribal area enroute 36200 0 36200 36200 138 right side of link

155 canal by lift

4 Tribal area in the 12514 0 12514 12514 48 vicinity of reservoirs

5 Tribal areas on right side of Narmada Main Canal by lift

a.Chhota Udepur 14940 8810 23750 23750 90 dist.

b.Panchmahal dist. 1833 8759 10592 10592 40

6 Supply of Provision of 76 MCM made for about 76 drinking water 27.5 lakh population of these areas. for all villages of Dang District and Villages of Kaprada & Dharmpur taluka of Valsad District.

7 Filling all Provision of 50 MCM water has been 50 possible tanks in kept for filling 2226 Panchayat and benefitted areas. village tanks/ check dams in benefit.

42368 42368 8 Target command 0 42368 161 in Saurashtra region

Sub Total 157291 74884 232175 232175

9 Environmental 20 releases

156 10 Evaporation losses 40

Total 1330 MCM

5.3.3 Floods and Drainage a) Par Basin

The Water Resources Department of Gujarat State is maintaining Nanivahiyal G & D site across Par river in the downstream of proposed Mohankavchali dam site. The observed monthly discharge data at Nanivahiyal G & D site is available for the period from 1966 to 2004. The maximum observed discharge at the G & D site was 3054 cumec in the year 1997. b) Auranga Basin

The observed monthly discharge data at 3 G & D sites viz., Amba, Bhervi and Asura are available for the period from 1962 to 2004, 1974 to 2006 and 1980 to 2005 respectively. These sites are located much in the downstream of proposed Chasmandva dam site. Bhervi G & D site covers the maximum catchment area of the basin and maximum observed discharge at this site was 3300 cumec in the year 2005. c) Ambica Basin

The observed monthly discharge data of 3 G & D sites viz., Gadat, Kudkas and Unai are available for the period from 1979 to 2004; 1980 to 2006; and 1979 to 2006 respectively. Gadat, and Unai G & D sites are located downstream of Chikkar and Dabdar dam sites where as the Kudkas site is located just upstream of Dabdar dam site. The maximum observed discharge at Gadat G & D sites was 2989 cumec in the year 2004. d) Purna Basin

The observed monthly discharge data of 3 G & D sites viz., Mahuva, Kalibel and Navsari are available for the period from 1979 to 2004; 1962 to 157 2000; and 1980 to 1997 respectively with some missing data. Mahuva and Navsari G & D sites are located much in the downstream of Kelwan dam whereas the Kalibel G & D site is located just upstream of Kelwan dam site. The maximum observed discharge at Mahuva G & D site was 8835 cumec in the year 1994.

5.3.4 River Geometry

The Par river travels mostly through hills covered with forest and patches of cultivated lands on banks of river. The Narriver is a Northern tributary of Par river. The Nar river flows towards west through Surgana taluka for its initial length of about 39 km. After forming the boundary between Maharashtra and Gujarat for a length of about 4.5 km, it enters the Dharampur taluka of Valsad district in the State of Gujarat and after flowing for about 39.5 km in south westerly direction, it joins the Par river near village Veribhavad at RL 72 m. The total length of river Nar is about 83 km. The diversion point identified across Nar river lies near village Paikhed at about 14 km upstream of its confluence with Par river.

The Auranga river traverses a distance of about 30 km from confluence of its tributaries before draining into the Arabian Sea. The area is hilly and covered with forest in the upstream reaches, while the area down- wards from about 15 km upstream of confluence of the Tan and the Man rivers is plain with cultivated lands. The Tanriver rises at an elevation of about 645 m and the elevation where it meets the Man river is about RL 50 m.

The Ambicariver after traversing a total distance of 164 Km joins the Arabian Sea in Gujarat. The important tributaries of the Ambica river are Khapri, Kaveri and Kharera rivers. The Khapri river rises at an altitude of 1030 m in Sahyadri hill range in Ahwa taluka of Dangs district in Gujarat and joins the river Ambica near village Milan at an elevation of 100 m. The length of river Khapri is about 80 km.

The Purna river after traversing a distance of 180 km it outfalls into the Arabian sea. The level of the river bed drops steeply from 1300 m at source to about 115 m at the proposed Kelwan dam site as the river in this reach passes through hilly area covered with dense forest and patches of

158 cultivated land. The important tributaries of the Purna river are Girna, Zankhari and Damaskhadi rivers.

5.3.5 Ground Water Recharge

During environmental impact assessment of Par-Tapi-Narmada link, detailed studies of ground water quality have been carried out during the year 2010-11.The details are furnished in Chapter-11 “Environmental Impact Assessment and Environment Management Plan”. The analysis of water level data in project area indicates a general rise in water level during monsoon season. The reservoir and link canal are likely to have a long term increase in water levels of the phreatic zones.

5.3.6 Reservoir Area

Six storage reservoirs are proposed for storing and diverting the water through Par-Tapi-Narmada link. These are Jheri dam across Par river; Paikhed dam across Nar river (a tributary of Par river); Chasmandva dam across Tan river (a tributary of Auranga river); Chikkar dam across Ambica river; Dabdar dam across Khapri river (a tributary of Ambica river); and Kelwan dam across Purna river. The Jheri reservoir is entirely lies in Maharashtra whereas, Dabdar and Kelwan reservoirs lies entirely in Gujarat. Other reservoirs namely Paikhed, Chasmandva and Chikkar reservoirs lie in both Gujarat and Maharashtra. The details of these reservoirs are described below: i) Jheri Reservoir

The Jheri reservoir is proposed across river Par near village Jheri in Peint taluka of Nasik district of Maharashtra (20°22'25" N and 73°25'51" E). The catchment area of Par basin up to proposed Jheri dam site is 425 km2 and lies entirely in Nasik district of Maharashtra. The Jheri reservoir area lies between latitudes 20o 19’ 20” N and 20o 24’ 15” N and longitudes 73o 25’ 39” E and 73o 31’ 28” E. The submergence area of the reservoir at FRL 246m is about 836 hectare of which 408 ha is forest area. The submergence area of the reservoir lies in Surgana and Peint taluka of Nasik

159 district in Maharashtra. The reservoir extends along Par river with fetch length of2.809 km. The deepest bed level of Par river at proposed Jheri dam site is 178 m. The live storage capacity of the proposed Jheri reservoir is 190.18 MCM.

The Jheri dam site is approachable from Peint as well as from Dharampur taluka head quarters in Nasik and Valsad districts respectively via Valsad - Nasik State highway. The nearest railway station is Nasik on Central Railway and nearest town is Peint, a taluka head quarter in Nasik district. ii) Paikhed Reservoir

The Paikhed reservoir is proposed across river Nar, a tributary of river Par near village Paikhed in Dharampur taluka of Valsad district in Gujarat (20°27'42" N and 73°23'37" E).The catchment area of Nar Sub-basin of Par basin up to proposed Paikhed dam site is 315 km2 of which 269 km2 in Surgana taluka of Nasik district in Maharashtra and 46 Km2 in Dharampur taluka of Valsad district in Gujarat. The Paikhed reservoir area lies between latitudes 20o 27’ 17” Nand 20o 29’ 47” N and longitudes 73o 24’ 07” E and 73o 28’ 24” E. The submergence area of the reservoir at FRL 248m is about 994 ha of which 317 ha is forest area. The submergence area of the reservoir lies in Surgana taluka of Nasik district of Maharashtra and Dharampur taluka of Valsad district in Gujarat. The reservoir extends along Nar river with fetch length of3.60 km. The deepest bed level of Nar river at proposed Paikhed dam site is 161.60 m. The live storage capacity of the Paikhed reservoir is 216.43 MCM.

The Paikhed dam site is approachable from Dharampur on Valsad – Nasik State highway. The nearest town is Dharampur and the nearest railway station is Valsad on Western Railway. iii) Chasmandva Reservoir

The Chasmandva reservoir is proposed across river Tan, a tributary of river Auranga near Chasmandva village in Dharampur taluka of Valsad district in Gujarat (20°37'02" N and 73°22'36" E). The catchment area of Auranga basin up to proposed Chasmandva dam site is 89 km2 of which 62 Km2 in Surgana taluka of Nasik district in Maharashtra and 27 km2 in

160 Dharampur taluka of Valsad district and Vansda taluka of Navsari district in Gujarat. The Chasmandva reservoir area lies between latitudes 20o 36’ 00” N and 20o 37’ 35” N and longitudes 73o 22’ 32” E and 73o 25’ 48” E. The submergence area of the reservoir at FRL 214.0m is about 615 ha of which 300 ha is forest area. The submergence area of the reservoir lies in Surgana taluka of Nasik district of Maharashtra and Dharampur taluka of Valsad district and Vansda taluka of Navsari district in Gujarat. The reservoir extends along Tan river with fetch length of4.38 km. The deepest bed level of Tan river at proposed Chasmandva dam site is 169.50 m. The live storage capacity of the Chasmandva reservoir is 75.86 MCM.

The Chasmandva dam site is approachable from Dharampur on Dharampur – Vansda road. The nearest town is Dharampur and the nearest railway station is Valsad on Western Railway. iv) Chikkar Reservoir

The Chikkar reservoir is proposed across river Ambica near village Chikkar in Ahwa taluka of Dangs district in Gujarat (20°42'00" N and 73°30'50" E). The catchment area of Ambica basin up to proposed Chikkar dam site is 304 km2 of which 102 km2 in Surgana taluka of Nasik district in Maharashtra and 202 km2 in Ahwa taluka of Dangs district in Gujarat. The Chikkar reservoir area lies between latitudes 20o 40’ 32” N and 20o 43’ 06” N and longitudes 73o 30’ 09” E and 73o 35’ 18” E. The submergence area of the reservoir at FRL 210m is about 742 ha of which 300 ha is forest area. The entire submergence area lies in Ahwa taluka of Dangs district in Gujarat. The reservoir extends along Ambica river with fetch length of2.815 km. The deepest bed level of Ambica river at proposed Chikkar dam site is 153.50 m. The live storage capacity of the Chikkar reservoir is 129.03 MCM. The Chikkar dam site is approachable from Waghai / Vansda on Gandevi – Saputara National Highway 360. The nearest town is Waghai and the nearest railway station is Waghai on narrow gauge (Bilimora – Waghai section) and Bilimora on Broad gauge of Western Railway. v) Dabdar Reservoir

The Dabdar reservoir is proposed across river Khapri, a tributary of river Ambica near village Dabdar in Ahwa taluka of Dangs district in Gujarat (20°48'58" N and 73°32'05" E). The catchment area of Ambica

161 basin up to proposed Dabdar dam site is 457 km2 entirely lies in Dangsdistrict in Gujarat. The Dabdar reservoir area lies between latitudes 20o 46’ 53” N and 20o 49’ 36” N and longitudes 73o 30’ 33” E and 73o 34’ 59” E. The submergence area of the reservoir at FRL 169m is about 1249 ha of which 614 ha is forest area. The entire submergence area lies in Ahwa taluka of Dangs district in Gujarat. The reservoir extends along Khapri river with fetch length of3.512 km. The deepest bed level of Khapri river at proposed Dabdar dam site is 113.0 m. The live storage capacity of the Dabdar reservoir is 201.06 MCM. The Dabdar dam site is approachable from Waghai on Gandevi – Saputara National Highway 360. The nearest town is Waghai and the nearest railway station is Waghai on narrow gauge (Bilimora – Waghai section) and Bilimora on Broad gauge of Western Railway. vi) Kelwan Reservoir

The Kelwan reservoir is proposed across river Purna near village Kelwan and Kakarda in Ahwa taluka of Dangs district in Gujarat (20°55'30" N and 73°32'00" E). The catchment area of Purna basin up to proposed Kelwan dam site is 694 km2 entirely lies in Dangsdistrict in Gujarat. The Kelwan reservoir area lies between latitudes 20o 53’ 04” N and 20o 57’ 31” N and longitudes 73o 31’ 23” E and 73o 37’ 20” E. The submergence area of the reservoir at FRL 164.0m is about 1629 hectare of which 890 ha is forest area. The entire submergence area lies in Ahwa taluka of Dangs district in Gujarat. The reservoir extends along Purna river with fetch length of5.382 km. The deepest bed level of Purna river at proposed Kelwan dam site is 116.0 m. The live storage capacity of the Kelwan reservoir is 258.28 MCM. The Kelwan dam site is approachable from Waghai on Gandevi – Saputara National Highway 360. The nearest town is Waghai and the nearest railway station is Unai on narrow gauge (Bilimora – Waghai section) and Vyara on Broad gauge (Surat – Bhusaval section).

The State – wise break-up of the catchment areas of Par, Auranga, Ambica and Purna basins and upto dam sites is given in Table 5.4:

Table 5.4 State-wise Break-up of the Catchment Area of Basins

162 Sl. River/ Basin Catchment Area (km2) No. Maharashtr Gujarat Total a 1 Par basin 773 875 1648 i Par basin upto Jheri dam site 425 - 425 ii Nar river (tributary of Par river) 269 46 315 upto Paikhed dam site 2 Auranga basin 150 598 748 i Tan river ( tributary of Auranga 62 27 89 river) upto Chasmandva dam site 3 Ambica basin 102 2583 2685 i Ambica basin upto Chikkar dam 102 202 304 site ii Khapri river (tributary of Ambica - 457 457 river) upto Dabdar dam site 4 Purna basin 58 2135 2193 i Purna basin upto Kelwan dam site - 694 694

5.3.7 Other Water Usage

The water stored in the Jheri, Paikhed, Chasmandva, Chikkar, Dabdar and Kelwan dams will mostly be used for irrigation and drinking purposes mostly in Tribal areas lying on en-route, in the vicinity / periphery of reservoirs, villages in the downstream and the targeted command area and to fill all possible tanks in the vicinity of benefitted area. In addition, 10% of lean season flow is also earmarked for environmental and ecological needs to sustain the aquatic life along the river course downstream of proposed dam sites. 5.3.8 Navigation

Rivers in Par-Tapi-Narmada system are presently not used for any major navigational purpose. There is no provision for navigation in the proposed Par-Tapi-Narmada link also.

5.4 Data Availability 5.4.1 Rainfall and Snowfall

There is no snowfall in Par, Auranga, Ambica and Purna basins involved in Par-Tapi-Narmada link project. The precipitation in the link project area is in the form of rainfall. There are number of Raingauge

163 stations and G & D sites in these basins where long term data is available. The basin wise availability of Rainfall data is described in following paragraphs: a) Par Basin There are ten raingauge stations located in and around the Par basin. The details of period of availability, average annual rainfall are given in Table 5.2 and location of these rain gauge stations are shown in Fig 5.5: Table 5.5 Period of Availability and Average Annual Rainfall

Sl.No. RG station Period of Average Annual Availability of Rainfall (mm) Data 1 Peint 1901 to 2008 2273 2 Pardi 1901 to 2003 1926 3 Mandva 1964 to 2007 2669 4 Panchalai 1969 to 2007 1920 5 Nanivahiya 1968 to 2006 2215 l 6 Dhamni 1969 to 2000 2019 7 Pindval 1977 to 2006 2406 8 Dharampur 1901 to 2003 2368 9 Surgana 1955 to 2006 1997 10 Bildha 1965 to 2006 2010 b) Auranga Basin There are ten raingauge stations located in and around the Auranga basin. The details of period of availability, average annual rainfall are given in Table 5.3 and location of these raingauge stations are shown in Fig 5.6:

Table 5.6 Period of Availability and Average Annual Rainfall

Sl.No. RG station Period of Availability Average Annual of Data (Year) Rainfall (mm) 1 Valsad 1901 to 2003 1890 2 Hanmatmal 1962 to 1998 2124 3 Bopi 1962 to 2006 2187 164 Sl.No. RG station Period of Availability Average Annual of Data (Year) Rainfall (mm) 4 Pindval 1977 to 2006 2406 5 Surgana 1955 to 2006 1997 6 Bildha 1965 to 2006 2010 7 Dharampur 1901 to 2003 2368 8 Pardi 1901 to 2003 1926 9 Rundhapura 1970 to 1998 1644 10 Chorvani 1963 to 2006 2001

165 166 167 c) Ambica basin

There are 25 raingauge stations located in and around the Ambica basin. The details of period of availability, average annual rainfall are given in Table 5.4 and location of these raingauge stations are shown in Fig 5.7:

Table 5.7 Period of Availability and Average Annual Rainfall

Sl.No. RG station Period of Availability Average Annual of Data Rainfall (mm) 1 Galkund 1964 to 2006 1669 2 Borkhal 1970 to 2006 1697 3 Kalibel 1962 to 2006 1559 4 Ahwa 1903 to 2003 1962 5 Surgana 1955 to 2006 1997 6 Jhuj 1969 to 2003 1973 7 Dharampur 1901 to 2003 2368 8 Saputara 1971 to 2006 2520 9 Rundhapura 1970 to 1997 1644 10 Chorvani 1963 to 2006 2001 11 Satem 1973 to 2001 1460 12 Waghai 1931 to 1997 1946 13 Vansda 1901 to 2003 1935 14 Garkhadi 1967 to 2006 1787 15 Antapur 1965 to 2006 1733 16 Mahuva 1962 to 2003 1419 17 Dholikuva 1969 to 2003 1953 18 Kalwada 1973 to 2006 1982 19 Chikhali 1901 to 2003 1800 20 Gandeva 1979 to 2006 1754 21 Dungari 1983 to 2006 1786 22 Amalsad 1973 to 2006 1599 23 Gandevi 1962 to 2006 1884 24 Astagam 1970 to 1997 1558 25 Sara 1977to 1997 1758

168 169 d) Purna Basin

There are 24 raingauge stations located in and around the Purna basin. The details of period of availability, average annual rainfall are given in Table 5.5and location of these raingauge stations are shown in Fig 5.8:

Table 5.8 Period of Availability and Average Annual Rainfall

Sl.No. RG station Period of Availability Average Annual of Data Rainfall (mm) 1 Laochali 1971 to 2006 1603 2 Dhanmodi 1971 to 2006 1295 3 Kalibel 1962 to 2006 1559 4 Ahwa 1903 to 2003 1972 5 Navsari 1927 to 2003 1469 6 Nizar 1963 to 2003 782 7 Jamkhadi 1965 to 2006 1617 8 Chimar 1971 to 1997 1217 9 Zankhari 1962 to 2006 1550 10 Raniamba 1969 to 2006 1538 11 Satem 1973 to 2001 1460 12 Subir 1964 to 2006 1601 13 Valod 1901 to 2003 1451 14 Garkhadi 1967 to 2006 1787 15 Antapur 1965 to 2006 1733 16 Mahuva 1962 to 2003 1419 17 Sarbhon 1973 to 2006 1420 18 Wankaner 1973 to 2006 1448 19 Ugat 1974 to 2002 1392 20 Vesma 1973 to 2006 1462 21 Maroli 1969 to 1997 1246 22 Vyara 1962 to 2003 1477 23 Astagam 1970 to 1997 1558 24 Dosvada 1972 to 2003 1279

170 171 The consistency check of rainfall data of all the stations have been carried out by Central Water Commission using double mass curve technique. The missing data have been estimated using normal ratio formula.

5.4.2 Pan Evaporation

There is no pan-evaporimeter installed in the project area. The monthly reservoir evaporation losses of existing Madhuban (Damanganga) reservoir (located in the vicinity of the project area of Par-Tapi-Narmada link) have been collected and adopted for simulation studies of reservoirs proposed under Par-Tapi-Narmada link. The monthly pan evaporation depths considered for the simulation study are given in Table 5.9:

Table 5.9 Monthly Pan Evaporation Depths Considered for Simulation Study Unit: mm/day Sl. Month Jheri Paikhed, Paikhed Barrage, No. Chasmandva, Chikkar and Ukai Dams Chasmandva Barrage, Dabdar and Kelwan 1 June 4.7 6.8 2 July 2.3 3.3 3 August 2.3 3.3 4 September 3.6 5.1 5 Oct 4.6 6.5 6 Nov 3.6 5.1 7 Dec 2.9 4.1 8 Jan 2.9 4.1 9 Feb 3 4.6 10 Mar 4.6 6.5 11 Apr 5.3 7.5 12 May 5.7 8.1 Source: Pan evaporation Source: Pan evaporation data data of Pinjal reservoir. of Damanganga reservoir.

5.4.3 Temperature, Relative Humidity, Wind Speed and Cloud (Climatological Parameters of the Project Area) 172 Two meteorological observatories viz., Surat and Vadodara maintained by IMD located adjacent to the project area have been used to characterize the climatic condition of the project area. The normal temperature, relative humidity, wind speed and cloud cover observed at Surat IMD observatory (based on the data for the period from 1998 to 2007) are furnished in Table 5.10A and Vadodara IMD observatories (based on the data for the period from 1998 to 2007) are furnished in Table 5.10B:

Table 5.10A Climatological Details Observed at Surat IMD Stations

Month Temperature Relative Wind Cloud Humidity Speed Cover (oC) (%) Max Min Max Min (km/h) (Okta) Jan 30.4 14.7 78 65 3.1 0.7 Feb 32.5 16.7 78 54 1.8 0.7 Mar 36.4 19.8 74 53 2.1 0.9 Apr 36.8 23.9 75 61 3.4 1.4 May 35.4 27.3 78 67 6.4 3.1 Jun 33.7 27.3 83 72 6.0 5.1 Jul 31.1 26.4 90 80 6.0 6.2 Aug 30.6 25.8 90 83 4.4 6.2 Sept 32.2 25.5 90 80 2.1 4.5 Oct 34.8 22.4 79 67 1.7 1.9 Nov 34.5 18.5 76 64 1.9 1.1 Dec 32.0 15.4 76 62 2.7 0.9

Table 5.10B Climatological Details Observed at Vadodara IMD Stations 173 Month Temperature Relative Wind Cloud Humidity Speed Cover (oC) (%) Max Min Max Min (km/h) (Okta) Jan 29.8 13.2 73 56 5.1 0.9 Feb 32.7 15.7 70 54 4.4 1.1 Mar 36.7 19.4 62 48 4.7 0.8 Apr 39.9 24.1 67 44 8.4 1.1 May 39.8 27.2 73 58 13.3 2.2 Jun 36.8 27.3 81 71 12.7 4.7 Jul 32.3 26.0 89 84 10.8 6.4 Aug 31.6 25.3 94 84 9.9 6.3 Sept 33.5 25.2 88 75 8.2 4.6 Oct 36.1 22.2 79 64 3.2 1.8 Nov 34.5 17.7 74 56 2.2 1.0 Dec 31.6 13.7 74 58 3.7 1.0

5.4.4 River Gauge and Discharge

The river gauge and discharge data is being observed by WRD, Government of Gujarat at Nanivahiyal G & D site across river Par; Amba across Tan, Bhervi across Auranga & Asura across Man all in Auranga basin; Kudkas across Khapri, Unai across Ambica river all in Ambica basin; and Kalibel and Navsari G&D sites across Purna river. The Central Water Commission is also observing Gadat G & D site across Ambica river and Mahuva G & D site across Purna river. The details of these G & D sites are given in Table 5.8 and location of these G & D sites are shown in Fig 5.2 to 5.5.

Table 5.11 Details of G & D Sites

Sl. G & D Maintaine River/ Catchment Data 174 No. Site d by Tributary Area (km2) Availability From To 1 Nanivahiyal Governme Par 1254.00 1966 2004 2 Amba nt of Auranga/ Tan 241.00 1962 2004 3 Bhervi Gujarat Auranga 628.65 1974 2006 4 Asura Auranga/ 309.29 1980 2005 Man 5 Gadat CWC Ambica 1510.00 1979 2004 6 Kudkas Governme Ambica/ 476.00 1980 2006 nt of Khapri 7 Unai Gujarat Ambica 1031.00 1979 2006 8 Mahuva CWC Purna 1750.00 1979 2004 9 Kalibel Governme Purna 720.85 1962 2000 10 Navsari nt of Purna 2012.00 1980 1997 Gujarat

5.4.5 Sediment (Suspended and Bed Load) Inflow and Grain Size Composition

The sedimentation observations are being carried out by Central Water Commission at Gadat G & D site across river Ambica, Mahuva G & D site across river Purna and by WRD, Government of Gujarat at Amba G & D site on Auranga river. The grain size composition observed for Gadat and Mahuva G & D sites maintained by Central Water Commission and Amba G & D site maintained by WRD, Government of Gujarat are furnished in Table 5.9. The average suspended load of sediment computed for 9 years found to be 0.244 mm/yr, 0.369 mm/yr and 0.383 mm/yr of catchment area for Gadat, Mahuva and Amba G & D sites respectively.

Table 5.12 Grain Size Composition

Sl. G & River Period of Grain size ( gram/litre)

175 No. D site Observation Medium Sand-silt Fine 1 Gadat Ambica 1979 to 2004 0.013310 0.013510 0.084900 2 Mahuva Purna 1970 to 2005 0.006540 0.007040 0.128540 3 Amba Auranga 1993 to 2007 0.191948 0.285153 0.058153

5.4.6 Water Quality

The surface water quality is being observed by Water Resources Department, Government of Gujarat at Nanivahiyal G & D site across Par river, Amba G & D site across Tan river (tributary of Auranga river) and by Central Water Commission at Mahuva Gauge and discharge site across Purna river. The data on various water quality parameters observed at these G & D sites is furnished at Table 5.10. As a part of the field study done for Environmental Impact Assessment ( EIA) studies, surface water samples were collected from Par, Auranga, Ambica and Purna river basins and analyzed for various physio-chemical parameters and details are furnished in Chapter- 11 “Environmental Impact Assessment and Environmental Management Plan”.The test results presented in this study indicate that quality of surface water is generally of safe category.

Ground water analysis for EIA studies has been done for the monsoon season 2010. It is found that the quality of ground water is satisfactory in the project area.

Table 5.13 Water Quality Data Observed at G & D Sites (Average for the Period from 1999 to 2005)

Sl. Code Name of Minerals/ Unit Limitation Name of G & D Sites No Chemical Min Max Nanivahiyal Amba Mahuv . on Par on a Tan on Purna

1 Alk Phen Alkalinity, mgCaCO3/ 0 3000 3.59 3.46 5.01 phenolphthalein L

2 ALK-TOT Alkalinity, total mgCaCO3/L 5 5000 119.62 126.6 144.66 8 3 Ca Calcium mg/L 0.5 1000 33.93 35.28 36.16 4 Cl Chloride mg/L 0.5 20000 30.39 37.94 49.51

5 CO3 Carbonate mg/L 0 1000 2.19 2.57 3.79 6 COD Chemical Oxygen mg/L 1 10000 16.40 9.25 10.53 Demand 7 DO Dissolved oxygen mg/L 0 30 8.59 8.12 7.86 8 DO_SAT% Dissolved Oxygen % 0 300 107.09 102.7 100.88 Saturation % 1 176 9 EC_FLD Electrical µmho/cm 5 10000 343.33 346.2 409.44 Conductivity Field 9 10 EC_GEN Electrical µmho/cm 5 10000 276.73 343.2 453.98 Conductivity 1 11 HAR_Ca Hardness, Calcium mgCaCO3/L 0.1 2000 84.83 88.21 90.39 12 HAR_ Hardness , Total mgCaCO3/L 0.1 2000 150.64 156.6 180.59 Total 0

13 HCO3 Bicarbonate mg/L 0.1 2000 117.34 124.4 142.25 1 14 K Potassium mg/L 0.1 1000 0.65 0.13 0.25 15 Mg Magnesium mg/L 0.1 1000 15.99 16.62 21.92 16 Na Sodium mg/L 1 20000 20.46 24.25 32.81 17 Na% Percent Sodium % 0.1 100 22.77 23.49 26.85 18 NH3-N Nitrogen, ammonia mg N/L 0.05 1000 0.09 0.09 0.14

19 NO2+NO3 Nitrogen, Total mg N/L 0.05 2000 0.98 0.68 0.78 Oxidised (NO2+NO3) 20 P-Tot Phosphorus, total mgP/L 0.00 100 0.63 0.50 0.56 1 21 pH_FLD pH_Field pH units 2 14 7.45 7.42 8.00 22 pH_GEN pH pH units 2 14 8.24 8.22 8.32 23 RSC Residual Sodium - 1 100 0.00 0.00 0.00 Carbonate 24 SAR Sodium Adsorption - 1 50 0.75 0.88 1.06 Ratio

25 SO4 Sulphate mg/L 1 3000 32.89 30.70 31.64 26 SS Solids, Suspended mg/L 0 3000 18.45 15.31 18.53 27 TDS Solids, Total mg/L 5 30000 181.08 223.6 298.73 Dissolved 3 28 Temp Temperature deg C 0.1 50 27.19 27.73 28.67 Source: State Water Data Centre, Government of Gujarat, Gandhinagar

5.5 Hydrological Data Requirement 5.5.1 Alternatives and Classifications

This information is not necessary for the present study.

5.6 Type of Inputs 5.6.1 Hydrological Inputs a) Temporal Data

For economic design of any hydraulic structure such as spillways, barrages etc. estimation of design flood is required. Diversion flood is required for estimation of carrying capacity of the diversion channel. Guidelines are available for selection of methodology for estimation of design flood. For major structures, the design flood is estimated using hydro-meteorological approach and the diversion flood is estimated mainly by frequency analysis of non-peak period flood. Hence, short duration rainfall-runoff data are required for estimation of design flood. Short 177 duration rainfall data are generally measured at the gauging stations / Automatic weather stations using self recording rain gauges. Hourly gauge data are required for estimation of short duration discharge data and non monsoon peak flow data are required for estimation of diversion flood.

To estimate the reservoir inflow, daily discharge series are required. In absence of daily series, ten-daily series can be used. For development of rainfall-yield relationship, daily / monthly average rainfall and concurrent stream flow data are required. The inflow to the reservoir is affected by water utilization at the upstream. Hence the utilization of water by the upstream projects is also required to compute the reservoir inflow. The periodic water demands and releases from the reservoir, and evaporation rates in the reservoir area are also required for simulation study of a reservoir. b) Spatial Data

For estimation of weighted rainfall, the locations of raingauges and the delineated basin boundary are required. The basin boundary also gives the area of the basin which can be used for other purposes such as synthetic hydrograph generation, application of conceptual models etc. For reservoir simulation the elevation-area-capacity data are required which can also be used for reservoir routing. c) Time Units for Simulation Studies

Two types of simulations are mainly carried out: a) routing of design flood through the reservoir to estimate the dam height, b) reservoir simulation with series of inflows and demands to estimate the reliability of the reservoir. For reservoir routing, hourly time unit is used. For reservoir simulation, monthly time unit is adopted.

5.7 Compilation and Processing of Basic Hydrological Data 5.7.1 Hydrological Investigation

The yield series have been developed using direct discharge data on catchment area proportionate where the proposed project is located near the G & D sites after checking the consistency of the observed data. The inconsistent data have been discarded and replaced by rainfall-runoff

178 modeling. Where the discharge data length is short, attempt has been made to extend the series through rainfall-runoff model. The yield series has been developed from the year 1975 onward for working out different dependabilities.

In Par basin the observed flow data is not available at or near the project locations as such the data available at the Nanivahiyal G & D site located across Par river quite downstream of proposed Jheri and Paikhed dam sites has been used to develop rainfall-runoff models to work out yield series at proposed Jheri and Paikhed dam sites. The yield series have been generated from year 1975 to 2006.

In Auranga basin the G & D data available at Amba G & D site across Tan river in the Downstream of Chasmandva dam site and covering an area of 241 km2 has been used to develop rainfall-runoff models to work out yield series at proposed Chasmandva dam. The yield series has been generated from year 1975 to 2006.

In Ambica basin the data available at Kudkas G & D site located across Khapri river just upstream of proposed Dabdar dam site has been used for Hydrological analysis at proposed Dabdar and Chikkar dam sites. The observed discharge data at Kudkas G & D site has been used to develop yield series for proposed Dabdar dam site from the year 1980 to 2006. The yield series has been further extended by using the rainfall-runoff model from 1975 to 1979. The proposed Chikkar and Dabdar dam sites are located very close to each other and have same hydro meteorological characteristics. Hence the G & D data available at Kudkas G & D site has been used for hydrological study of Chikkar dam also. The yield series at proposed Chikkar dam has been developed for the period from 1975 to 2006 using rainfall-runoff model developed at Kudkas G & D site.

In Purna basin the data available at the Kalibel G & D site located across Purna river just upstream of Kelwan dam site has been used to develop the yield series at proposed Kelwan dam site. There are some gaps in discharge data of Kalibel G and D site and observed data is available upto the year 2000 only. Hence, the gaps and the series beyond the year 2000 have been worked out by rainfall-runoff model. The data of inconsistent years have also been generated by rainfall-runoff model.

179 5.7.2 Data from Other Sources

The data used in this study were collected from various agencies. Rainfall, climatological and evapotranspiration data were collected from IMD and State Water Data Center (SWDC), Gandhinagar. G & D data was collected from Central Water Commission and State Water Data Center (SWDC) of Gujarat State. The data related to Water Resources projects such as location, water utilization and other salient features were collected from Water Resources Departments of the concerned State Governments.

5.7.3 Processing of Data

The time units of available and required time series data are often different. Further, the short duration discharges are not measured but are estimated from the gauge records. This requires preliminary processing of thetime series data. Following hydrological variables were processed in this study: (i) rainfall data (ii) gauge and discharge data.

5.7.3.1 Quality of Data

As indicated earlier the rainfall data at above raingauge stations and G & D data at the respective G & D sites is available for varying periods with some missing records for shorter durations. These missing record values have been estimated using standard statistical methods. The data observed at these sites have been checked for consistency and homogeneity. Both internal and external consistency checks were made on discharge data.

5.7.3.2 Filling of Short Data Gaps

The period of availability of rainfall data at above stations varies and in many cases the data are available for short duration only. However, in the Par basin from the year 1966 to 2006, in the Auranga basin from the year 1962 to 2006, in the Ambica basin from the year 1970 to 2006 and in the Purna basin from the year 1962 to 2006, the rainfall is mostly available for all the stations and the same has been considered in this study. Still there are some gaps in the rainfall data and these gaps have been filled using standard procedure. These gaps have been filled by the normal ratio formula as given below.

Px = Nx/m[ P1/N1+ P2/N2+ ……… Pm/Nm] Where,

Px is estimated rainfall of a station for a particular month and year

180 Nx is average rainfall of the station for that particular month

P1, P2…… Pm are observed rainfall of nearby stations in that particular month and period

N1 N2…….Nm are average rainfall of nearby stations for that particular month Using above procedure, gaps in rainfall data have been filled up and the same has been used in working out the weighted average rainfalls in the catchments. 5.7.4 Consistency of Data 5.7.4.1 Consistency Check of Rainfall Data For this study, the Double Mass Curve (DMC) analysis is used to check the consistency of a rainfall series and adjustment of records. This analysis is based on the principle that when each recorded data comes from the same parent population, they are consistent. The consistency of rainfall data of all the stations have been checked using double mass curve technique. Plotsof mass curvesindicate that the rainfall data is more or less consistent for almost all the stations. Only the rainfall data of Panchalai rain gauge station in Par basin is showing some inconsistency as indicated in Fig 5.6.

Fig 5.6: Rainfall Data of Panchalai Raingauge Station

On scrutiny, the rainfall data of Panchalai for the year 1995, 1996 and 1997 are showing inconsistency and found to be on lower side as compared to rainfall of other stations. The rainfall during these years was also

181 compared with observed discharges during the corresponding years. The runoff is not showing any significantly lower values during these years. Hence, the rainfall data of Panchalai station has been modified suitably. The mass curve after correcting the inconsistent data is shown in Fig 5.7.

Fig 5.7: Mass Curve after Correcting the Inconsistent Data of Panchalai Station

5.7.4.2 Weighted Mean Rainfall

There are ten rain gauge stations in and around the Par basin; ten raingauge stations in and around the Auranga basin; twenty five rain gauge stations in and around the Ambica basin; and twenty four rain gauge stations in and around the Purna basin. The Weighted Mean Rainfall for the whole basins, catchments upto the proposed dam sites and upto the G & D sites have been estimated by Thiessen Polygon Method. The Isohyetal map of Par, Auranga, and Ambica and Purna basins is at Fig 5.8 to 5.11 respectively.

182 `

183 184 185 186 187 5.7.4.3 Consistency Check of Discharge Data

G & D data of all the sites have been checked for consistency and homogeneity. Both internal and external consistency checks have been made on discharge data. i) Internal Consistency a) Single Mass Curve

Single mass curve for each site has been prepared and the plots are shown in Fig 5.12 to 5.18.

Fig 5.12: Single Mass Curve of Nanivahiyal G & D Site in Par Basin

188 Fig 5.13: Single Mass Curve of Amba G & D Site in Auranga Basin

Fig 5.14: Single Mass curve of Bhervi G & D Site in Auranga Basin

Fig 5.15: Single Mass Curve of Gadat G & D Site in Ambica Basin

189 Fig 5.16: Single Mass Curve of Kudkas G & D Site in Ambica Basin

Fig 5.17: Single Mass Curve of Mahuva G & D Site in Purna Basin

190 Fig 5.18: Single Mass Curve of Kalibel G & D Site in Purna Basin b) Concurrent Plots

Concurrent plots for each basin have been prepared and the plots are shown in Fig – 5.19 to 5.22:

Fig 5.19: Concurrent Plot of Nanivahial Site in Par Basin

191 Fig 5.20: Concurrent Plot of Discharge of all Stations in Auranga Basin

Fig 5.21: Concurrent Plot of Discharge of all Stations in Ambica Basin

192 Fig 5.22: Concurrent Plot of Discharge of all Stations in Purna Basin c) Homogeneity Tests

FandT tests were also made on discharge data to check the homogeneity. F-test is used to determine whether two samples have different variances and t-Test is used to determine whether two samples are likely to have come from the same two underlying populations that have the same mean. The discharge data for all the G & D sites have been found more or less homogeneous. However, Runoff factors have also been checked as detailed below in addition to homogeneity checks before adopting the discharge data. ii) External Consistency

The discharge data of all sites were also compared with corresponding rainfall by plotting monsoon yield vs. monsoon rainfall and also computingrun-off factors. a) Nanivahiyal G & D Site on Par River

The monsoon rainfall-runoff plot for Nanivahiyal G & D Site is at Fig 5.23(A); monthly rainfall-runoff plot for Nanivahiyal G & D Site for the year 1981 is at Fig 5.23(B) and monsoon rainfall-runoff plot for Nanivahiyal G & D Site after discarding inconsistent years is at Fig 5.24. The runoff factors are in Table 5.11.

193 Fig 5.23(A) Monsoon Rainfall-Runoff Plot for Nanivahiyal G & D Site in Par Basin

The flow data of the year 1981, 1984 and 2002 do not appear consistent with respect to corresponding weighted rainfall.

Fig 5.23(B) Monthly Rainfall-Runoff Plot for year 1981 at Nanivahiyal G & D Site in Par Basin

The runoff is more than rainfall in almost each month during the year and therefore runoff data of year 1981does not appears consistent. The runoff factors of this year also show inconsistency.

194 Table 5.14 Monsoon Rainfall-Runoff Consistency at Nanivahiyal G & D site Year WMR (mm) Runoff (mm) Runoff factor

1966 2263 900 0.40 1967 2071 780 0.38 1969 2412 1812 0.75 1970 2120 1156 0.55 1971 2134 1217 0.57 1972 1492 458 0.31 1973 2474 1434 0.58 1974 1093 257 0.23 1975 2122 1559 0.73 1976 3230 3021 0.94 1977 2453 1402 0.57 1978 1973 939 0.48 1979 1853 912 0.49 1980 2050 1073 0.52 1981 2680 3803 1.42 1982 1859 1552 0.83 1983 2487 1456 0.59 1984 1691 1509 0.89 1985 1567 825 0.53 1986 1376 687 0.50 1987 1376 716 0.52 1988 2144 1166 0.54 1989 1601 834 0.52 1990 2411 1000 0.41 1991 1990 927 0.47 1992 2149 1008 0.47 1993 1970 1177 0.60 1994 3156 2004 0.64 1995 1423 661 0.46 1996 1975 1086 0.55 1997 2008 1399 0.70 1998 1936 900 0.47 1999 1996 824 0.41 2000 1540 681 0.44 2001 1801 980 0.54 2002 2010 475 0.24 2003 2396 1019 0.43 2004 2726 1160 0.43

The flow data of inconsistent years have been discarded while developing rainfall-runoff modeling for working out the yield series.

195 Fig 5.24 Monsoon Rainfall-Runoff Plot for Nanivahiyal G & D Site after Discarding Inconsistent Data b) Bhervi G & D Site on Auranga River

Monsoon Rainfall-Runoff Plot for Bhervi G & D Site is at Fig 5.25

Fig 5.25: Monsoon Rainfall-Runoff Plot at Bhervi G & D Site

The flow data of the year 1975,76,77,91,95,2005 and 2006 does not appear consistent with respect to corresponding weighted rainfall. The flow

196 data of these years was also checked on monthly basis. Monthly Rainfall-Runoff Plots for years 1975,76,77,91, 2005 and 2006 are at Fig 5.26 to 5.31:

Fig 5.26: Monthly Rainfall-Runoff Plot for year 1975 at Bhervi G & D Site

Fig 5.27: Monthly Rainfall-Runoff Plot for year 1976 at Bhervi G & D Site

197 Fig 5.28: Monthly Rainfall-Runoff Plot for year 1977 at Bhervi G & D Site

Fig 5.29: Monthly Rainfall-Runoff Plot for year 1991 at Bhervi G & D Site

198 Fig 5.30: Monthly Rainfall-Runoff Plot for year 2005 at Bhervi G & D Site

Fig 5.31:Monthly Rainfall-Runoff Plot for year 2006 at Bhervi G & D Site

The flow data of these years show inconsistency in most of the months and therefore were discarded while developing rainfall-runoff modeling or working out the yield series. The flow data of rest of year have been used in developing rainfall-runoff relationship. The Rainfall-Runoff Plot at Bhervi G & D site after removing data of inconsistent years is at Fig 5.32.

Fig 5.32: Monsoon Rainfall-Runoff Plot at Bhervi G & D Site after Discarding Inconsistent Data

199 c) Amba G & D Site Tan River

Monsoon Rainfall-Runoff Plot for Amba G & D Site across Tan river in Auranga basin is at Fig 5.33.

Fig 5.33: Monsoon Rainfall-Runoff Plot at Amba G & D Site

The flow data of the year 1964, 1966, 1968 and 1986 does not appear consistent with respect to corresponding weighted rainfall. The flow data of these years was also checked on monthly basis. The monthly rainfall – runoff plot for these years are at Fig 5.34 to 5.37.

Fig 5.34: Monthly Rainfall-Runoff Plot for year 1964 at Amba G & D Site

200 Fig 5.35: Monthly Rainfall-Runoff Plot for year 1966 at Amba G & D Site

Fig 5.36: Monthly Rainfall-Runoff Plot for year 1968 at Amba G & D Site

201 Fig 5.37: Monthly Rainfall-Runoff Plot for year 1986 at Amba G & D Site

The flow data of these inconsistent years have been discarded and rainfall-runoff model developed using consistent data only. The rainfall- runoff plot after removing data of inconsistent years is at Fig – 5.38:

Fig 5.38: Monsoon Rainfall-Runoff Plot at Amba G & D Site after Discarding Inconsistent data

202 d) Gadat G & D Site at Ambica River The monsoon rainfall-runoff plot at Gadat G & D site across river Ambica is at Fig – 5.39. Flow data of Gadat G & D site appears to be consistent.

Fig 5.39: Monsoon Rainfall-Runoff Model at Gadat G & D Site e) Kudkas G & D Site on Khapri River The monsoon rainfall-runoff plot at Kudkas G & D site across river Khapri is at Fig 5.40. Flow data of Kudkas G & D site appears to be consistent.

Fig 5.40: Monsoon Rainfall-Runoff Plot at Kudkas G & D Site

203 f) Mahuva G & D Site on Purna River

The monsoon rainfall-runoff plot at Mahuva G & D site across river Purna is at Fig 5.41. Flow data of Mahuva G & D site appears to be consistent.

Fig 5.41: Monsoon Rainfall-Runoff Plot at Mahuva G & D Site g) Kalibel G & D Site on Purna River

The monsoon rainfall-runoff plot at Kalibel G & D site across river Purna is at Fig 5.42

Fig 5.42: Monsoon Rainfall-Runoff Plot at Kalibel G & D Site 204 The flow data of the year 1967, 1969, 1970, 1976, 1984 and 2000 does not appear consistent with respect to corresponding weighted rainfall. The flow data of these years has been discarded. The rainfall-runoff model has been developed using consistent data only. The monthly rainfall – runoff plot for these years are at Fig 5.43 to 5.48.

Fig 5.43: Monthly Rainfall-Runoff Plot for year 1967 at Kalibel G & D Site

Fig 5.44: Monthly Rainfall-Runoff Plot for year 1969 at Kalibel G & D Site

205 Fig 5.45: Monthly Rainfall-Runoff Plot for year 1970 at Kalibel G & D Site

Fig 5.46: Monthly Rainfall-Runoff Plot for year 1976 at Kalibel G & D Site

206 Fig 5.47: Monthly Rainfall-Runoff Plot for year 1984 at Kalibel G & D Site

Fig 5.48: Monthly Rainfall-Runoff Plot for year 2000 at Kalibel G & D Site

The flow data of the years 1967, 1969, 1970, 1976, 1984 and 2000 have been discarded and rainfall-runoff model developed using consistent data. Monsoon Rainfall-Runoff plot at Kalibel G & D Site after discarding inconsistent years is at Fig 5.49.

207 Fig 5.49: Monsoon Rainfall-Runoff Plot at Kalibel G & D Site after Discarding Inconsistent Years

5.7.5 Presentation of Data 5.7.5.1 Rainfall Data

For carrying out the hydrological analysis of an area the average rainfall over that area is required. The rainfall data observed at rain-gauge station represents only point sampling of the areal distribution of a storm. The point rainfall values at various stations can be converted into an average value over the area by three methods: (i) Arithmetic average or mean (AM) method, (ii) Isohyetal method, and (iii) Thiessen polygon (TP) method. In the present study, the arithmetic average or mean (AM) method has been used for double mass curve analysis and Thiessen polygon (TP) method has been used for estimation of average areal rainfall over the study area for rainfall-runoff analysis and estimation of yields through regression from rainfall.

5.7.5.2 Discharge / Yield Data

The observed daily discharge data are available from 1962 onwards with some missing records for Nanivahiyal, Bhervi, Amba, Gadat, Kudkas, Mahuva and Kalibel G & D sites. This daily discharge data have been aggregated to work out the monthly yield at respective G & D sites.

208 5.8 Water Availability/Inflows 5.8.1 Storage Projects

Six storage projects: Jheri reservoir across river Par, Paikhed reservoir across river Nar (tributary of Par river); Chasmandva reservoir across river Tan in Auranga basin; Chikkar reservoir across Ambica river, Dabdar reservoir across Khapri river in Ambica basin; and Kelwan reservoir across Purna river are envisaged in Par-Tapi-Narmada link project, for which simulation study has been carried out.

5.8.2 Approach in the Current Study

In the present studies the yield series have been developed using direct discharge data on catchment area proportion where the proposed project is located near the G & D sites after checking the consistency of the observed data. The inconsistent data have been discarded and replaced by rainfall-runoff modeling. Where the discharge data length is short, attempt has been made to extend the series through rainfall-runoff model. Normally the yield series has been developed from the year 1975 onward.

In Par basin and Auranga basin, the observed flow data is not available at or near the project locations and therefore, rainfall-runoff models have been used to work out yield series. The series have been generated from year 1975 to 2006. In Ambica basin, the observed discharge data have been used to develop yield series for Dabdar dam from the year 1980 to 2006. The yield series has been further extended by using the rainfall-runoff model from 1975 to 1979. For Chikkar dam, the yield series has been developed using rainfall-runoff model from 1975 to 2006. In Purna basin the yield series for Kelwan dam has been developed using the discharge data of Kalibel G & D site. There are some gaps in discharge data of Kalibel G & D site and observed data is available upto the year 2000 only. Hence, the gaps and the series beyond the year 2000 have been worked out by rainfall-runoff model. The data of inconsistent years have also been generated by rainfall-runoff model.

5.8.3 Hydrological Inputs Required for Simulation

The natural water availability at Jheri, Paikhed, Chasmandva, Chikkar, Dabdar and Kelwan project locations is mainly confined to

209 monsoon months (June to Sept) and these projects are being planned for storages. For such storage projects as per the “Guidelines for preparation of Detailed Project Report of Irrigation and Multi Purpose projects, 2010” the minimum length of hydrological inputs required is about 25 years. Accordingly, the yield series have been generated on monthly basis for 30- 35 years period. The contribution of non-monsoon period, which is very nominal, has been added on lumped basis.

5.8.3.1 Water Inflow in to Storage Reservoirs

The water inflows into proposed reservoirs at Jheri and Paikhed dams in Par basin; Chasmandva dam in Auranga basin; Chikkar and Dabdar dams in Ambica basin and Kelwan damin Purna basin have been computed by regression analysis using discharge data of Nanivahiyal, Amba, Kudkas, and Kalibel G & D sites respectively and the same have been used for simulation study of the link project.

5.8.3.2 Rainfall – Runoff Relationship

The concurrent weighted mean rainfall and runoff data have been used to derive rainfall-runoff models. The inconsistent data points, if any, have been discarded. Rainfall-runoff relationship has been developed for monsoon period. The monthly models for the monsoon period (June to September) have also been developed to disaggregate the monsoon yield into monsoon months.

The rainfall-runoff relations developed at the G & D sites for monsoon period are shown in Fig 5.50 to 5.56:

210 Fig – 5.50: Monsoon Rainfall – Runoff Model at Nanivahiyal G & D Site

Fig – 5.51: Monsoon Rainfall – Runoff Model at Bhervi G & D Site

211 Fig – 5.52: Monsoon Rainfall – Runoff Model at Amba G & D Site

Fig – 5.53: Monsoon Rainfall – Runoff Model at Gadat G & D Site

212 Fig – 5.54: Monsoon Rainfall – Runoff Model at Kudkas G & D Site

Fig – 5.55: Monsoon Rainfall – Runoff Model at Kalibel G & D Site

213 Fig – 5.56: Monsoon Rainfall – Runoff Model at Mahuva G & D Site

The monthly rainfall-runoff models have also been developed at above G & D sites. The details of monthly models are given in Table 5.15:

Table 5.15 Monthly Rainfall-Runoff Models Developed at Various G & D sites Sl. Month Gauge and Discharge Site No Nanivahiyal in Bhervi in Amba in . Par Basin Auranga Basin Auranga Basin (1) (2) (3) (4) (5) 1 Jun Y=0.27764 x - Y=0.61052 x Y=0.31484 x 48.56 -123.54 -51.08 2 Jul Y=0.79357 x Y=0.88427 x Y=0.6026 x -300.83 -300.18 -147.24 3 Aug Y=0.61543 x Y=0.94561 x Y=0.85518 x +26.81 -167.09 -77.16 4 Sept Y=0.73749 x Y=0.7342 x Y=0.81117 x +22.75 -11.70 -33.14

Table 5.15 (contd..) 214 Sl Month Gauge and Discharge Site No Gadat in Kudkas in Mahuva in Ambica Basin Ambica Basin Purna Basin (1) (2) (6) (7) (8) 1 Jun Y=0.25697 x – Y=0.37931 x Y=0.04388 x 30.92 -71.66 -5.69 2 Jul Y=0.83023 x Y=0.47828 x Y=0.80448 x -324.60 -139.04 -243.15 3 Aug Y=0.47714 x Y=0.64783 x + Y=0.88019 x +69.31 19.64 -110.86 4 Sept Y=0.80751 x Y=0.84862 x Y=0.66988 x -19.35 -14.82 -12.78

Table 5.15 (contd.) Sl No Month Kalibel in Purna Basin (1) (2) (9) 1 Jun Y=0.15192 x – 8.18 2 Jul Y=0.42232 x -102.78 3 Aug Y=0.91623 x -142.07 4 Sept Y=0.81182 x -29.76

The monsoon model is generally found more robust and realistic to the catchment behavior as compared to monthly models as it represents lumped rainfall runoffprocess for the entire season and most of the monthly fluctuations get compensated. Therefore, monsoon model has been used to derive the monsoon yield. Monthly models have been used to disaggregate the monsoon yield into monthly yields.

The non monsoon yield has been taken as the percentage of monsoon yield based on the observed discharge data of the respective G & D sites. The percentage of non-monsoon flow to monsoon flow at Various G & D sites are given in Table – 5. 16: Table – 5.16 Percentage of Non Monsoon Flow to Monsoon Flow Sl. G & D Site % of Non Monsoon Flow to Monsoon Flow No. 1 Nanivahiyal 8.87 2 Bhervi 8.81 3 Amba 5.78 4 Gadat 9.59 5 Kudkas 9.31 215 6 Mahuva 12.04 7 Kalibel 10.78

Even during non monsoon months, flows are mainly limited to October and November months and there is hardly any flow after December month.

5.8.3.3 Gross Yield Series

In Par basin Gauge and Discharge data at Nanivahiyal G & D site (located quite downstream of proposed Mohankavchali, Jheri and Paikhed dams) is available for the period from 1966 to 2004. The same has been used for developing the monthly and monsoon Rainfall-Runoff models at Nanivahiyal G & D site. Using the Rainfall-Runoff modeling at Nanivahiyal G & D site, the yield series have been generated from 1975 to 2006 on monthly basis for whole Par basin and proposed Jheriand Paikhed dams.

In Auranga basinthe Gauge and Discharge data of Bhervi G & D site across Auranga river is available for the period from 1974 to 2006 and has been used for developing the monthly and monsoon Rainfall - Runoff models. Using Rainfall - Runoff models developed at Bhervi G & D site, the yield series for whole Auranga basin has been developed from 1975 to 2006. Gauge and Discharge data at Amba G & D site across Tan river located downstream of proposed Chasmandva dam is available for the period from 1962 to 2004. The data of Amba G & D site have been used for developing the monthly and monsoon Rainfall - Runoff models. Using Rainfall - Runoff models at Amba G & D site, the yield series at proposed Chasmandva dam site has been developed from 1975 to 2006. In Ambica basin the Gauge and Discharge data at Gadat G & D site located across Ambica river is available for the period from the year 1979 to 2004 and same has been used for developing the monthly and monsoon Rainfall - Runoff models. Using Rainfall Runoff models developed at Gadat G & D site, the yield series for whole Ambica basin has been generated for the period from 1975 to 2006. Gauge and Discharge data at Kudkas G & D site located just upstream of the proposed Dabdar reservoir across Khapri river (tributary of Ambica river) is available from the year 1980 to 2006. The yield series at proposed Dabdar dam site has been generated from year 1980 to 2006 on catchment area proportionate basis, using observed data after duly checking the consistency. The inconsistent data have been

216 modified using Rainfall - Runoff modeling. As rainfall data is available for long period, the same has been used to extend the yield series from 1975 to 1979 using Rainfall - Runoff modeling developed at Kudkas G & D site. Thus the yield series from 1975 to 2006 has been used for working out the water availability at the Dabdar dam site. Rainfall-Runoff models developed at Kudkas G & D site have been used to derive the yield series at proposed Chikkar dam site. The yield series at proposed Chikkar dam site has been generated from 1975 to 2006.

In Purna basinfor working out the water availability for whole Purna basin the monthly and monsoon Rainfall - Runoff models have been developed at Mahuva G & D site where discharge data is available from the year 1979 to 2004. The yield series for whole Purna basin has been generated from 1975 to 2006 using Rainfall - Runoff modeling. Gauge and Discharge data at Kalibel G & D site is available for the period from the year 1962 to 2000 except for the years 1979, 1980, 1991, 1992, 1993 to 1996 and 1999. The site is located just upstream of the proposed Kelwan dam site across Purna river. The yield series at Kelwan dam sites has been generated from year 1975 to 2000 on catchment area proportionate basis, using observed data after duly checking the consistency. The inconsistent data and gaps have been filled by using Rainfall - Runoff models. The yield series has been further extended beyond year 2000 using Rainfall - Runoff models. The yield series from 1975 to 2006 has been used for working out the water availability at the Kelwan dam site.

The water availability for whole Par basin and at proposed Jheri and Paikhed dam sites; Auranga basin and at proposed Chasmandva dam site; Ambica basin and at proposed Chikkar and Dabdar dam sites; and Purna basin and at proposed Kelwan dam site as derived from the gross yield series at various dependabilities are given in Table 5.17. The Gross yield series at above locations are given at Annexure – 5.1 to 5.10 in Volume – II of DPR .

Table 5.17 Gross Annual Yield

217 Sl. Basin / Dam Site Gross Annual Yield (MCM) No Average 50% 75% . Dependability Dependability 1 Par basin 2160 1922 1726 2 Jheri dam site 528 467 391 3 Paikhed dam site 380 335 264 4 Auranga basin 1092 983 858 5 Chasmandva dam site 102 91 70 6 Ambica basin 2800 2430 1914 7 Chikkar dam site 304 257 220 8 Dabdar dam site 488 455 323 9 Purna basin 1667 1419 1101 10 Kelwan dam site 497 445 362

5.8.3.4 Net Yield Series The net water availability at proposed Jheri, Paikhed, Chasmandva, Chikkar, Dabdar and Kelwan dam sites has been worked out after subtracting all the consumptive upstream utilizations planned by the basin States. The planned utilizations upto proposed Jheri, Paikhed, Chasmandva, Chikkar, Dabdar and Kelwan dam sites is given in Table 5.18. The Net yield series at above locations isgiven at Annexure 5.11 to 5.16 in Volume- IIof DPR . Table 5.18 Planned Utilizations Upstream of Proposed Dam Sites upto Sl Type of Jheri Dam Site(MCM) Paikhed Dam Site (MCM) No. Demand Existing Ongoing Proposed Total Existing Ongoing Proposed Total Projects Projects Projects Projects Projects Projects 1. Irrigation 6.49 1.58 11.09 19.16 1.61 - 11.32 12.93 2. Hydro ------3. Domestic 1.30 1.83 4. Industrial 3.94 3.99 5. Envr.and - 3.06 Ecologica l Total 24.40 21.81

Table – 5.18 (contd.) Planned Utilisation Upstream of Proposed Dam Sites upto 218 Sl Type of Chasmandva Dam Site (MCM) Chikkar Dam Site (MCM) No. Demand Existing Ongoing Proposed Total Existing Ongoin Proposed Total Projects Projects Projects Projects g Projects Projects 1. Irrigation - - 5.88 5.88 - - 52.79 52.79 2. Hydro ------3. Domestic 0.27 0.64 4. Industrial 0.85 2.20 5. Envr.and 0.59 2.42 Ecological Total 7.59 58.05

Table – 5.18 (contd.) Planned Utilisation Upstream of Proposed Dam Sites upto Sl Type of Dabdar Dam Site (MCM) Kelwan Dam Site (MCM) No. Demand Existing Ongoing Proposed Total Existing Ongoin Proposed Total Projects Projects Projects Projects g Projects Projects 1. Irrigation - - 61.54 61.54 - - 52.47 52.47 2. Hydro ------3. Domestic 3.88 5.22 4. Industrial 5.53 7.53 5. Envr.andE 3.93 4.10 cological Total 74.88 69.32

Regeneration from major and medium irrigationprojects has been taken as 10 percent while the same has been neglected in case of minor irrigation projects. The regeneration from domestic and industrial uses has been considered as 80 percent. The net consumptive abstraction considering from regeneration due to planned projects in upstream is estimated and shown in Table 5.19:

Table 5.19 Net Consumptive Abstraction U/S of Dam Sites and Downstream Requirement 219 Dam Site Abstraction U/S of Dam Sites (MCM) Environmental Irrigation Hydro Domestic Industrial Total and Ecological (Minor) D/s of Dam (MCM) Jheri 19.16 0 0.26 0.79 20.21 - Paikhed 12.93 0 0.37 0.8 14.1 3.06 Chasmandva 5.80 0 0.05 0.17 6.02 0.59 Chikkar 50.29 0 0.13 0.44 50.86 2.42 Dabdar 58.67 0 0.78 1.11 60.56 3.93 Kelwan 52.47 0 1.04 1.51 55.02 4.10

The net yield series have been generated at proposed Jheri, Paikhed, Chasmandva, Chikkar, Dabdar and Kelwan dam sites after deducting the net consumptive utilizations upto dam sites from the gross yields. The net yield at all the 6 dam sites at various dependabilities as worked out is furnished in Table 5.20: Table 5.20 Net Yield (MCM) at Dam Sites Diversion point Average 50% dependability 75% dependability Jheri 508.7 446.3 371.1 Paikhed 366.6 320.8 249.9 Chasmandva 96.1 84.9 64.0 Chikkar 254.7 206.2 169.7 Dabdar 429.9 394.2 262.0 Kelwan 443.5 390.3 307.6

The Water Availability Study report of Par-Tapi-Narmada link (March, 2012) carried out by hydrological Studies Organization of Central Water Commission is given at Appendix 3.1 inVolume - IVof DPR.

5.8.3.5 Diversion and Small Pondages

It is proposed to divert 1210 MCM through Par-Tapi-Narmada linkcanal from all the proposed reservoirs for utilization in en-route of link canal for irrigation, drinking water supply mostly in tribal areas and filling tanks/Check dams in the benefitted areas and also to take over the part command area of existing Miyagam Branch Canal of Narmada Canal System. The Narmada water so saved will be utilized by substitution in the tribal areas of Chota Udepur and Panchamahal Districts and water short Saurashtra region to provide irrigation and drinking water facilities. Details of diversion quantity are given in Table 5.21:

220 Table 5.21 Details of Diversion Quantity Sl. Dam Diversion No. Quantity (MCM) 1 Jheri 176 2 Paikhed 250 3 Chasmandva 64 4 Chikkar 150 5 Dabdar 262 6 Kelwan 308 Total 1210

5.9 Sedimentation Studies 5.9.1 Revised Area Capacity Curves

Reservoir sedimentation studies for all the6 reservoirs proposed in Par-Tapi-Narmada link project have been carried out by Hydrological Studies organization, Central Water Commission, New Delhi. The Report on Sedimentation Study of Par-Tapi-Narmada link project is at Appendix 5.2 in Volume – IV of the DPR of link project prepared by NWDA in August, 2015.Sediment data measurements are being observed in three rivers only: Ambica, Purna and Auranga rivers. Data for Par and Nar basins are not available. Using the observed values of daily discharge and sediment concentration, sedimentation rate in the 3 river basins were assessed and are given below in Table 5.22:

Table 5.22 Suspended Sediment Rate Sl. G & D River Sediment Rate (mm/year) No. Site Suspended Load (SL) Total Load (1.15*SL) 1 Gadat Ambica 0.2443 0.2810 2 Mahuwa Purna 0.3693 0.4247 3 Amba Auranga 0.3831 0.4406

The sedimentation rates observed at G & D data sites are relatively lower as compared to sediment rate based on hydrographic survey of five reservoirs in the region and much lower than the generalized siltation rate recommended for the region (west flowing rivers beyond Tapi) in the “Compendium of Silting of Reservoirs in India” (Table 5.23:)

221 Table 5.23 Average and Median Values of Rate of Siltation taken from “Compendium on Silting of Reservoirs in India” Zone for Region No. of Average Median Sedimentatio Reservoir Siltation Siltation n s Rate Rate Rate Under mm/yr mm/yr Study 6 Narmada and Tapi 3 0.729 0.75 Basin 7 West Flowing 19 3.533 1.79 Rivers beyond Tapi and South Indian Rivers

The hydrographic survey of five existing reservoirs in the region indicates sedimentation rate of 7.15 ha m/ 100 km2/year. The hydrographic Survey of Madhuban reservoir in Damanganga basin, which lies towards south of Par-Tapi-Narmada link projects, gave sedimentation rate of 8.94 ha m / 100 km2/yr. Normal rainfall in Damanganga basin is higher than the normal rainfall in river basins of Par-Tapi-Narmada link and therefore sedimentation rate of 7.15 ha m / 100 km2/yr, as assessed based on hydrographic survey of existing reservoirs in the region, appears in order. However, the land use changes are likely to impact the sediment generation from the catchment in the future with increasing human activities such as agriculture etc. Presently the catchment of these river basins particularly the upper catchment are not significantly affected by the human activities. Impact of climate change is likely to increase rainfall intensities and extreme meteorological events. In view of above factors, the observed sedimentation rate of 7.15 ha m/100 km2/ year is enhanced by 25% and sedimentation rate of 8.94 say 9 ha m/100 km2/yr has been adopted in the analysis of all the seven reservoirs in the Par-Tapi-Narmada link.

The sedimentation distribution in reservoir submergence has been carried out for two periods viz. 50 years and 100 years using Empirical area reduction method as per IS: 5477 (part-2) 1994, ‘Fixing the capacities of reservoirs’. The Jheri reservoir has been classified as Type – III(Hill) and remaining 6 reservoirs have been classified as Type – II(Flood plain foot hill). The total quantity of sediment likely to be deposited in 50-years and

222 100-years of life in the reservoirs and corresponding New Zero Elevations as estimated are given in Table 5.24:

Table 5.24 50 Year and 100 Year Sediment Volume and New Zero Elevation Sl. Reservoir After 50 Years After 100 Years No. Sediment New Zero Sediment New Zero Volume Elevation Volume Elevation (MCM) (m) (MCM) (m) 1 Jheri 18.01 185.00 35.94 198.50 2 Paikhed 13.57 164.34 27.11 171.88 3 Chasmandva 3.88 171.75 7.76 176.00 4 Chikkar 13.04 162.10 26.03 169.30 5 Dabdar 19.55 119.90 39.03 126.90 6 Kelwan 29.90 122.20 59.69 128.20

The original and revised Elevation – Area – Capacity curve after 50 years and 100 years for Jheri reservoir are given at Fig 5.57 and 5.58.

223 Fig- 5.57: Original and Revised Elevation Area Capacity Curve for Jheri Dam after 50 Years

224 Fig- 5.58: Original and Revised Elevation Area Capacity Curve for Jheri Dam after 100 Years

The original and revised Elevation – Area – Capacity curve after 50 years and 100 years for Paikhed reservoir are given at Fig 5.59 and 5.60.

225 Fig- 5.59: Original and Revised Elevation Area Capacity Curve for Paikhed dam after 50 Years

Fig- 5.60: Original and Revised Elevation Area Capacity Curve for Paikhed dam after 100 Years

226 The original and revised Elevation – Area – Capacity curve after 50 years and 100 years for Chasmandva reservoir are given at Fig 5.61 and 5.62.

Fig- 5.61: Original and Revised Elevation Area Capacity Curve for Chasmandva dam after 50 Years

227 Fig- 5.62: Original and Revised Elevation Area Capacity Curve for Chasmandva dam after 100 Years

The original and revised Elevation – Area – Capacity curve after 50 years and 100 years for Chikkar reservoir are given at Fig 5.63 and 5.64.

Fig- 5.63: Original and Revised Elevation Area Capacity Curve for Chikkar dam after 50 Years

228 Fig- 5.64: Original and Revised Elevation Area Capacity Curve for Chikkar dam after 100 Years

The original and revised Elevation – Area – Capacity curve after 50 years and 100 years for Dabdar reservoir are given at Fig 5.65 and 5.66.

Fig- 5.65: Original and Revised Elevation Area Capacity Curve for Dabdar dam after 50 Years

229 Fig- 5.66: Original and Revised Elevation Area Capacity Curve for Dabdar dam after 100 Years

The original and revised Elevation – Area – Capacity curve after 50 years and 100 years for Kelwan reservoir are given at Fig 5.67 and 5.68

Fig- 5.67: Original and Revised Elevation Area Capacity Curve for Kelwan dam after 50 Years

230 Fig- 5.68Original and Revised Elevation Area Capacity Curve for Kelwan dam after 100 Years

5.10 Potential Evapotranspiration and Rainfall

Normal potential evapotranspiration data of Surat IMD observatory were used for estimation of water utilization of various projects upstream of Jheri, Paikhed, Chasmandva, Chikkar, Dabdar and Kelwan dams and the data of Vadodara IMD observatory has been used to work out the crop water requirement for the various crops in the en-route command area. The month wise observed/computed value of potential evapotranspiration at Surat and Vadodara observatories is furnished at Table 5.25:

Table 5.25 Month wise Observed/Computed Potential Evapotranspiration (mm)

Month Monthly Mean Evapotranspiration ETO Surat Vadodara Jan 99.6 98.7 Feb 144.9 113.4 Mar 162.4 162.6 Apr 185.7 192.8 May 202.0 246.4 231 Jun 152.4 197.8 Jul 109.2 128.2 Aug 107.9 114.9 Sep 114.6 129.6 Oct 141.5 143.1 Nov 116.2 111.0 Dec 99.2 92.9

5.11 Inputs for Water Quality

Different parameters of water quality are observed regularly at Nanivahiyal on Par, Amba on Tan and Mahuva Gand D (State) site on Purna river by Water Resources Dept, Government of Gujarat. The details of water quality had been already briefed at Para 5.4.6. Also, as part of the field study done for Environmental Impact Assessment studies by WAPCOS Ltd., for the link project while preparing the DPR in August, 2015. Surface water samples were collected from various rivers in the project area and analyzed for various physio-chemical parameters for ascertaining the water quality status in the project area during summer, winter and monsoon seasons. The details are furnished in Chapter- 11 “Environmental Impact Assessment and Environmental Management Plan” of the DPR of link project prepared by NWDA in August, 2015. The laboratory test results carried out for collected water samples indicate that the quality of surface water is generally of safe category.

5.12 Low Flow Inputs

The WRD, Government of Gujarat is observing Gauge and Discharge data at Nanivahiyal G & D site across river Par; Amba across Tan, Bhervi across Auranga and Asura across Man all in Auranga basin; Kudkas across Khapri, Unai across Ambica river all in Ambica basin; and Kalibel and Navsari G & D sites across Purna river. The Central Water Commission is also observing the Gauge and Discharge data at Gadat G & D site across Ambica river and Mahuva G & D site across Purna river. Daily G & D data at these G & D sites is available for varying period (Table 5.8). Analysis of the observed daily discharge data at these G & D sites indicates that the flow in these rivers is zero during summer months every year.

5.13 Surface to Ground Water Recharge

232 The quantum of water proposed to be transferred through Par – Tapi - Narmada link project is of the order of 1210 MCM annually, utilizing382 MCM for en-route irrigation, 285 MCM for Projects proposed by the Government of Gujarat on the left side of the canal, 138 MCM for Tribal area enroute right side of canal, 48 MCM Tribal area in the vicinity of reservoirs, 90 MCM and 40 MCM for Tribal areas on right side of Narmada Main Canal by liftin Chhota Udepur dist and Panchmahal dist. respectively, 48 MCM towards Supply of drinking water for all villages of Dang District and Villages of Kaprada and Dharampur taluka of Valsad District, 18 MCM for Filling all possible tanks in benefitted areas, 161 MCM for Target command in Saurashtra region. As the bottom surface and both side slopes of the entire link canal for diverting the above water will be lined with cement concrete, there may not be much seepage loss to the ground water. Thus, the hazards of water logging and salinization is not anticipated in the region.

5.14 Data for Studies other than Simulation 5.14.1 Design Flood and Diversion Flood Studies of Dams

The Par-Tapi-Narmada link project envisages total 6 dams; Jheri across river Par, Paikhed across river Nar (a tributary of Par river); Chasmandva across river Tan in Auranga basin; Chikkar across Ambica river; Dabdar across river Khapri (a tributary of Ambica river); and Kelwan across river Purna. Two weirs one each in the downstream of Paikhed and Chasmandva dam sites are also proposed. The Design Flood and Diversion Flood studies at all the six dams and 2 barrages proposed in Par – Tapi – Narmada link project have been carried out by Hydrological Studies Organization, Central Water Commission, New Delhi. The Reports on flood study of Par-Tapi-Narmada Link, Part-I covering the design and diversion flood studies of dams carried out by Central Water Commission are at Appendix 3.3 in Volume-IV of the DPR of link project prepared by NWDA in August, 2015.

Hydro-meteorological approach has been used for computing design flood and diversion flood. The catchment response functions have been derived using Regional Flood Estimation Report. The short interval observed discharge data and concurrent rainfall data are not available at any of the 7 dam sites proposed in Par-Tapi-Narmada link, as such, the unit hydrographs at the proposed dam sites and barrage sites have been derived synthetically based on physiographic characteristics using Flood Estimate

233 Report. The storm studies as carried out by IMD, have been used in the study. The 100/50 year return period rainfalls have been adopted from the State-wise isopluvial maps published by IMD. The time distribution has been supplied by IMD and used in the study. Loss rate parameters have been taken from Regional Flood Estimation Report. The base flows have been assessed based on observed flood events. The design flood and diversion flood studies carried out for the dams are briefly described below:

5.14.1.1 Derivation of Unit Hydrograph

Short interval observed discharge and concurrent rainfall data is not available at the project sites and therefore, the unit hydrograph at the project location has been derived synthetically using FER. i) Physiographic Characteristics

The physiographic parameters for derivation of unit hydrograph at the dam sites such as catchment area, slope (s) and length of river etc have been derived using Survey of India Topo - sheets in 1: 50000 scale. Physiographic parameters as derived are given in Table 5.26:

Table 5.26 Physiographic Parameters at Dam Sites Sl Parameter Catchmen Length of Equivalent L/S No Dam Site t Area (A) River (L) Slope (S) . km2 km m/km 1 Jheri 425 57.67 7.41 7.78 2 Paikhed 315 70.60 5.27 13.40 3 Chasmandva 89 21.75 8.43 2.58 4 Chikkar 304 53.40 5.59 9.55 5 Dabdar 457 74.85 4.32 17.33 6 Kelwan 694 88.95 3.73 23.85 ii) Unit Hydrograph Parameters

Considering the physiographic parameters as above, UG parameters have been computed based on “Flood Estimation Report 5 (a) and 5 (b) for West Coast Region, Konkan and Malabar Coasts”. The UG Parameters are given in Table 5.27:

234 Table 5.27 Unit Hydrograph Parameters at Dam Sites Sl. Parameter Unit Jheri Paikhed No. (1) (2) (3) (4) (5) 1 qp = 0.9178*(L/S)^-0.4313 cumec 0.379 0.300 2 tp=1.5607*(qp)^-1.0814 hr 4.500 5.500 3 W50 =1.9251*(qp)^-1.0896 hr 5.540 7.150 4 W75 =1.0189*(qp)^-1.0443 hr 2.810 3.580 5 WR50 =0.5788*(qp)^-1.1072 hr 1.690 2.200 6 WR75=0.3469*(qp)^-1.0538 hr 0.960 1.230 7 TB =7.3801*(tp)^0.7343 hr 22.000 26.000 8 Tm =tp+tr/2 hr 5.000 6.000 9 Qp =qp*A cumec 161.000 94.500 10 ∑Qi =A*d/tr*0.36 cumec 1181.000 875.000 d=1.00cm ,tr=1hrs

Table 5.27 (contd.) Unit Hydrograph Parameters Sl. Parameter Unit Chasm Chikk Dabdar Kelwan No. andva ar (1) (2) (3) (6) (7) (8) (9) 1 qp = 0.9178*(L/S)^- cume 0.610 0.347 0.268 0.234 0.4313 c 2 tp=1.5607*(qp)^-1.0814 hr 2.500 4.50 6.50 7.500 3 W50 =1.9251*(qp)^- hr 3.300 6.10 8.08 9.370 1.0896 4 W75 =1.0189*(qp)^- hr 1.710 3.08 4.03 4.640 1.0443 5 WR50 =0.5788*(qp)^- hr 1.000 1.87 2.49 2.890 1.1072 6 WR75=0.3469*(qp)^- hr 0.580 1.06 1.39 1.600 1.0538 7 TB =7.3801*(tp)^0.7343 hr 14.000 22.00 29.00 32.000 8 Tm =tp+tr/2 hr 3.000 5.00 7.00 8.000 9 Qp =qp*A cume 54.290 105.49 122.48 162.400 c 10 ∑Qi =A*d/tr*0.36 cume 247.00 844.00 1269.0 1928.00 c 0 0 0 d=1.00cm ,tr=1hrs

235 Using the above parameters, unit hydrograph for the catchments upto all the 6 dam sites have been derived. The finalized Unit Hydrograph for various dam sites are given at Fig 5.69 to 5.74

Fig 5.69: Unit Hydrograph for Jheri Dam Site

Fig 5.70: Unit Hydrograph for Paikhed Dam Site

236 Fig 5.71: Unit Hydrograph for Chasmandva Dam Site

Fig 5.72: Unit Hydrograph for Chikkar Dam Site

237 Fig 5.73: Unit Hydrograph for Dabdar Dam Site

Fig 5.74: Unit Hydrograph for Kelwan Dam Site iii) Validation of Unit Hydrographs

Observed short interval discharge and corresponding rainfall data are not available at project locations. Therefore, the synthetic unit hydrographs as derived above could not be validated by observed data.

5.14.1.2 Design Storm Studies i) PMP Studies 238 The storm study for the project has been carried by IMD. Earlier the storm studies were submitted by IMD in year 2010. However, IMD was requested to review the storm study as the 1-day SPS and PMP values supplied by IMD appeared on lower side. The storm study has been reviewed by IMD and revised storm values were received in May, 2012.

The following rainstorms were considered by IMD:

 1-3 July 1941 (Centered at Dharampur, North – West of Project)  9-10 July 1958 (Centered at Ghatghar, South-East of Project)

The rainstorm of 1-3 July 1941 (Centered at Dharampur) has been found the severe most rainstorms in the vicinity of the project catchment for 1-day and 2-day design storm values. The SPS, PMP and MAF (Moisture Adjustment Factor) values as finalized by IMD are in Table 5. 28: Table 5.28 SPS, PMP and MAF Values

Sl. Diversion Site SPS (cm) PMP (cm) MAF No. 1 day 2 day 1 day 2 day 1 Jheri 77.5 111.8 90.7 130.8 1.17 2 Paikhed 78.7 114.5 92.1 134.0 1.17 3 Chasmandva 98.8 126.0 115.6 147.4 1.17 4 Chikkar 78.4 114.4 91.7 133.7 1.17 5 Dabdar 75.9 110.0 88.8 128.7 1.17 6 Kelwan 64.5 99.1 75.5 115.9 1.17

However, it is seen that in transposition of 1941 Dharampur storm to the catchment of Jheri dam by IMD, the storm pattern has been moved quite considerably even towards ridge line (eastward) though it is mentioned in the report that the storm pattern has been moved along ridge line only ( north-south). This has resulted in transposed depth of 77.5 cm. The Hydrological Studies Organization (HSO) of Central Water Commission is of the view that the movement of storm towards ridge line should be very limited. Central Water Commission has worked out the transposed depth by restricting the movement of storm pattern towards ridge line and one day transposed depth works out as 63.5 cm. applying the MAF of 1.17, the one day PMP works out as 74.3 cm which has been adopted as one day design storm for estimating PMF. 239 ii) 50 and 100 Year Return Period Rainfall

50/100-year return period point rainfalls have been taken from the isopluvial maps published by IMD recently. 50/100-year return period point rainfall and areal rainfall for various reservoirs are given in Table 5.29:

Table 5.29 50 and 100 Year Return Period Rainfall Sl. Flood Area 24 hr Point Point to Areal 24 hr No. Rainfall Rainfall Area Ratio* l RF (km2) (cm) (cm) 1 Jheri Dam 50-Year Return Period 425 40 0.86 34.40 100-Year return period 425 44 0.86 37.84 2 Paikhed Dam 50-Year Return Period 315 44 0.88 38.72 100-Year return period 315 48 0.88 42.24 3 Chasmandva Dam 50-Year Return Period 89 52 0.95 49.4 100-Year return period 89 54 0.95 51.3 4 Chikkar Dam 50-Year Return Period 304 44 0.88 38.72 100-Year return period 304 48 0.88 42.24 5 Dabdar Dam 50-Year Return Period 457 42 0.85 35.7 100-Year return period 457 46 0.85 39.1 6 Kelwan Dam 50-Year Return Period 694 38 0.82 31.16 100-Year return period 694 42 0.82 34.44 *source: Flood Estimation Report (5a and 5b) iii) Storm Duration

As base period of unit hydrograph is less than 24 hrs for Jheri, Paikhed, Chasmandva and Chikkar dams, hence storm duration of 24 hrs has been used in the study of these dams. Base period for Dabdar and Kelwan dams is more than 24 hrs, hence storm duration of 48 hrs has been used in the study of these dams. iv) Time Distribution of Rainfall 240 A time distribution of 24 hour rainfall into short interval rainfall as supplied by IMD is given in Table 5.30. Time distribution curve is at Fig 5.75.

Table 5.30 Time Distribution Time (hrs) 0 3 6 9 12 15 18 21 24

TD% 0 33 54 67 77 85 92 97 100

Fig - 5.75:Time Distribution Curve

The 3 hourly Time distribution supplied by IMD given has been interpolated to derive hourly distribution as given in Table 5.31 and 5.32:

Table 5.31

24 Hour % Time Distribution Coefficient (TD) for Jheri Dam Time (hr) 1 2 3 4 5 6 7 8 9 10 11 12

(TD) 14 24 33 41 48 54 59 63 67 71 74 77 Time (hr) 13 14 15 16 17 18 19 20 21 22 23 24

(TD) 80 83 86 88 90 92 94 96 97 98 99 100

Table 5.32

24 Hour %Time Distribution Factors (TD) for the Dams 241 Except Jheri Dam Time (hr) 1 2 3 4 5 6 7 8 9 10 11 12

(TD) 11 22 33 40 48 54 59 63 67 71 74 77 Time (hr) 1 14 15 16 17 18 19 20 21 22 23 24 3

(TD) 8 82 85 87 90 92 94 96 97 98 99 100 0

As the design storm depth is to be convoluted as two bells per day approach, time distribution coefficients for 12 hour rainfall has been worked out based on 24 hour distribution as given in Table 5.33 and 5.34:

Table 5.33 12 Hour Time Distribution Coefficients for Jheri Dam Time (hr) 1 2 3 4 5 6 7 8 9 10 11 12

(TD) 18 31 43 53 62 70 77 82 87 92 96 100

Table 5.34 12 Hour Time Distribution Coefficients for the Dams Except Jheri Dam Time (hr) 1 2 3 4 5 6 7 8 9 10 11 12

(TD) 14 29 43 52 62 70 77 82 8 92 96 100 7 v) Design Loss Rate

A loss rate of 0.19 cm/hr (modal loss rate) as recommended in the Flood Estimation Report for sub zone 5(a) and 5(b) has been adopted for computing 50/100 year return period floods. A lower loss rate of 0.10 cm/hr has been considered for PMF estimation.

5.14.1.3 Convolution

The rainfall excess has been convoluted with the unit hydrograph developed for dams to compute Direct Surface Runoff Ordinate (DSRO). A base flow at the rate of 0.15 cumec / km2 has been added to the ordinates of the DSRO to get the design flood hydrograph ordinates.

5.14.1.4 Design Flood (PMF)

242 The design flood hydrograph for all the 7 dams are at Fig 5.76 to 5.81 and the design peak flood as worked out is given in Table 5.35:

Table 5. 35 Design Peak Flood for Various Dams Dam Design Peak Flood (cumec) Jheri 6539 Paikhed 5307 Chasmandva 2578 Chikkar 5649 Dabdar 6683 Kelwan 7979

Fig - 5.76: Design Flood Hydrograph for Jheri Dam

243 Fig - 5.77: Design Flood Hydrograph for Paikhed Dam

Fig - 5.78: Design Flood Hydrograph for Chasmandva Dam

244 Fig - 5.79: Design Flood Hydrograph for Chikkar Dam

Fig - 5.80: Design Flood Hydrograph for Dabdar Dam

245 Fig - 5.81: Design Flood Hydrograph for Kelwan Dam

5.14.1.5 Diversion Flood i) Diversion Flood (50 Year Return Period)

The 50 year return period hydrograph for all the 6 dams are at Fig 5.82 to 5.87 and 50 year return period peak flood as worked out is given in Table 5.36: Table 5. 36 50 Year Return Period Peak Flood for Various Dams Dam 50 Year Return Period Peak Flood (cumec) Jheri 2703 Paikhed 2017 Chasmandva 1024 Chikkar 2167 Dabdar 2539 Kelwan 3102

246 Fig - 5.82: 50 Year Return Period Diversion Flood Hydrograph for Jheri Dam

Fig - 5.83: 50 Year Return Period Diversion Flood Hydrograph for Paikhed Dam

247 Fig - 5.84: 50 Year Return Period Diversion Flood Hydrograph for Chasmandva Dam

Fig - 5.85: 50 Year Return Period Diversion Flood Hydrograph for Chikkar Dam

248 Fig - 5.86: 50 Year Return Period Diversion Flood Hydrograph for Dabdar Dam

Fig - 5.87: 50 Year Return Period Diversion Flood Hydrograph for Kelwan Dam

ii) Diversion Flood (100 Year Return Period)

249 The 100 year return period hydrograph for all the 6 dams are at Fig5.88 to 5.93 and 100 year return period peak flood as worked out is given in Table 5.37: Table 5.37 100 Year Return Period Peak Flood for Various Dams Dam 100 Year Return Period Peak Flood (cumec) Jheri 2989 Paikhed 2211 Chasmandva 1065 Chikkar 2374 Dabdar 2796 Kelwan 3428

Fig - 5.88: 100 year Return Period Diversion Flood Hydrograph for Jheri Dam

250 Fig - 5.89: 100 year Return Period Diversion Flood Hydrograph for Paikhed Dam

Fig - 5.90: 100 year Return Period Diversion Flood Hydrograph for Chasmandva Dam

251 Fig - 5.91: 100 year Return Period Diversion Flood Hydrograph for Chikkar Dam

Fig - 5.92: 100 year Return Period Diversion Flood Hydrograph for Dabdar Dam

252 Fig - 5.93: 100 year Return Period Diversion Flood Hydrograph For Kelwan Dam

5.14.1.6 Conclusion

The design flood (PMF) and 50 year return period and 100 year return period diversion floods estimated by hydro-meteorological approach as above for all the 6 dams proposed in Par-Tapi-Narmada link are given in Table 5.38:

Table 5.38 Design flood (PMF) and Diversion Flood of Par-Tapi-Narmada link project Sl. Diversion Site PMF Diversion Flood (cumec) No. (cumec) with Return Period 50 year 100 year 1 Jheri 6539 2703 2989 2 Paikhed 5307 2017 2211 3 Chasmandva 2578 1024 1065 4 Chikkar 5649 2167 2374 5 Dabdar 6683 2539 2796 6 Kelwan 7979 3102 3428

5.14.2 Design Flood and Diversion Flood Studies of Barrages

Two barrages one each in the downstream of Paikhedand Chasmandva dam sites are also proposed in Par-Tapi-Narmada link project. 253 The flood studies of these weir sites have been carried out by Hydrological Studies Organization of Central Water Commission. The Reports on flood study of Par-Tapi-Narmada link, Part-II covering the design flood studies for diversion barrages carried out by Central Water Commission are at Appendix –3.4 in Volume - IV.The flood studies at the 6 dam sites are described in Para 5.14.1 and the similar studies at the weir sites are described below.

The flood studies at Paikhed and Chasmandva barrage sites have been carried out using hydro-meteorological approach. The whole catchment upto weir site has been divided into two sub catchments: i) Sub catchment upto respective dam site located in the upstream, and ii) sub catchment below dam upto weir site. The flood hydrograph worked out at dam site was suitably routed upto weir site and routed hydrograph was added to the flood hydrograph of free catchment to assess the resulting flood hydrograph at the weir site. As all the six dams proposed in Par-Tapi-Narmada link project are large dams and the spillway of the dams shall be designed corresponding to PMF, the peak of incoming SPF, 500 year and 100 year return period flood hydrograph is likely to be less than spillway capacity and therefore, the effect of reservoir routing has been ignored and outflow from these dams has been assumed same as inflow hydrograph at respective dam. The outflow hydrograph for the respective dams has been channel routed for dam site to respective weir site using Muskingum method.

5.14.2.1 Derivation of Unit Hydrograph

Short interval observed discharge and concurrent rainfall data is not available at the project sites and therefore, the unit hydrograph for the free catchment between dam site and Barrage site has been derived synthetically using “Flood Estimation Report 5 (a) and 5 (b) for West Coast Region, Konkan and Malabar Coasts”. i) Physiographic Characteristics

The physiographic parameters for derivation of unit hydrograph for the free catchment between dam site and Barrage site such as catchment area, slope and length of river etc have been derived using Survey of India Topo sheets in 1: 50000 scale. Physiographic parameters as derived are given in Table 5.36.

254 Table 5.36 Physiographic Parameters at Barrage Sites (Free Catchment) Sl. Barrage site Parameter (Free Catchment below Dam Site) No Catchment Length of Equivalent L/S . Area (A) River (L) Slope (S) km2 km m/km 1 Paikhed 12 8.25 12.42 0.66 2 Chasmandva 41 13.35 8.22 1.62 ii) Unit Hydrograph Parameters

Considering the physiographic parameters as above, UG parameters for the free catchment between dam site and Barrage site have been computed based on “Flood Estimation Report 5 (a) and 5 (b) for West Coast Region, Konkan and Malabar Coasts”. The UG Parameters are given in Table 5.40.

Table 5.40 Unit Hydrograph Parameters (Free Catchment between Dam Site and Barrage Site)

Sl. Parameter Unit Paikhed Chasmandva No Barrage Barrage . 1 qp = 0.9178*(L/S)^-0.4313 cumec 1.095 0.745 2 tp=1.5607*(qp)^-1.0814 hr 1.5 2.5 3 W50 =1.9251*(qp)^-1.0896 hr 1.74 2.65 4 W75 =1.0189*(qp)^-1.0443 hr 0.93 1.39 5 WR50 =0.5788*(qp)^-1.1072 hr 0.52 0.8 6 WR75=0.3469*(qp)^-1.0538 hr 0.32 0.47 7 TB =7.3801*(tp)^0.7343 hr 10 14 8 Tm =tp+tr/2 hr 12 3 9 Qp =qp*A cumec 13.1 30.6 10 ∑Qi =A*d/tr*0.36 cumec 33 114 d=1.00cm ,tr=1hrs Using the above parameters, unit hydrograph for the free catchment between dam site and Barrage site for the 2 weir sites have been derived.

255 The finalized Unit Hydrograph for the free catchment between various dam sites and Barrage sites are given at Fig 5.94 to 5.95.

Fig - 5.94: Unit Hydrograph for Paikhed Barrage Site due to Free Catchment between Dam Site and Barrage Site

Fig - 5.95: Unit Hydrograph for Chasmandva Barrage Site due to Free Catchment between Dam Site and Barrage Site iii) Validation of Unit Hydrographs

256 Observed short interval discharge and corresponding rainfall data are not available at project locations. Therefore, the synthetic unit hydrographs as derived above could not be validated by observed data.

5.14.2.2 Design Storm Studies i) SPS Studies

The storm study for the project has been carried out by IMD. The details are described in Para 5.14.1.2. The SPS values for all the 6 dams as finalized by IMD are given in Table 5.28.

Using the storm pattern given in the IMD report, the Central Water Commission has estimated the SPS value for the free catchment between dam site and weir site for the 2 weir sites. As free catchment below the respective dam sites up to respective Barragesites is very small, the critical placement of the storm pattern as adopted for assessing the transposed depth for the catchments upto dam sites has been adopted for assessing the transposed storm depths for the sub catchments upto Barragesite. The transposed depth (SPS) values for the free catchment between dam sites and Barrage sites as estimated by Central Water Commission is given in Table 5.41.

Table 5.41 SPS Values for Free Catchment between Dam Sites and Barrage Sites Weir Site Duration SPS (cm) Paikhed 1 day 87.48 Chasmandva 1 day 98.80 ii) 100 Year and 500 Year Return Period Rainfall

100 year return period point rainfalls have been taken from the isopluvial maps published by IMD recently. The Central Water Commission has assessed 500 year Return Period rainfall for the dam site as well as for the free catchment between respective dam sites and barragesites by Gumbel method (XT= X +KT *σn-1 ) X and σn-1 were assessed using various return period rainfall given in isopluvial maps of IMD as given in Table 5.42.

Table 5.42 Gumbel Parameters 257 Dam / Weir Site Gumbel Parameter

X σn-1 Paikhed Dam 22 cm 7.545 Paikhed Barrage (Free catchment 26 cm 8.415 between dam and weir sites) Chasmandva Dam 24 cm 8.706 Chasmandva Barrage (Free 26 cm 9.286 catchment between dam and weir sites)

100 year and 500 year return period point rainfall and areal rainfall are given in Table 5.43.

Table 5.43 100 Year and 500 Year Return Period Rainfall

Sl. Flood Area 24 hr Point to Areal 24 hr No. Point Rainfall Ratio* Area Rainfall l RF (km2) (cm) (cm) 1 Paikhed dam 100-Year return period 315 48 0.88 42.24 500-Year return period 315 58 0.88 51.00 2 Paikhed Barrage (free catchment)

100-Year return period 12 55 0.88 48.40 500-Year return period 12 67 0.88 59.00 3 Chasmandva dam 100-Year return period 89 54 0.94 50.80 500-Year return period 89 66 0.94 62.00 4 Chasmandva Barrage (free catchment) 100-Year return period 41 58 0.94 54.50 258 500-Year return period 41 70.8 0.94 66.60 *source: Flood Estimation Report (5a and 5b) iii) Storm Duration

As base period of unit hydrograph is less than 24 hr, storm duration of 24 hr has been used in the study. iv) Time Distribution of Rainfall

Time distribution of 24 hour rainfall into short interval rainfall as supplied by IMD is given in Table 5.44. Time distribution curve is at Fig 5.96. Table - 5.44 Time Distribution

Time (hrs) 0 3 6 9 12 15 18 21 24

TD% 0 33 54 67 77 85 92 97 100

Fig – 5.96: Time Distribution Curve

The 3 hourly Time distribution supplied by IMD has been interpolated to derive hourly distribution as given in Table 5.45.

Table 5.45

24 Hour % Time Distribution Coefficient (TD)

Time (hr) 1 2 3 4 5 6 7 8 9 10 11 12

(TD) 14 24 33 41 48 54 59 63 67 71 7 77 259 4 Time (hr) 13 14 15 16 17 18 19 20 21 22 2 24 3

(TD) 80 83 86 88 90 92 94 96 97 98 9 100 9

As the design storm depth is to be convoluted as two bells per day approach, time distribution coefficients for 12 hour rainfall has been worked out based on 24 hour distribution are as given in Table 5.46.

Table 5.46 12 Hour Time Distribution Coefficients

Time (hr) 1 2 3 4 5 6 7 8 9 10 11 12

(TD) 1 3 43 53 62 70 77 82 87 92 96 10 8 1 0 v) Design Loss Rate

A loss rate 0.19 cm/hr as recommended in the Flood Estimation Report for sub zone 5(a) and 5(b) has been adopted for computing 100 year return period floods. A lower loss rate of 0.10 cm/hr has been considered for SPF estimation.

5.14.2.3 Convolution

The rainfall excess has been convoluted with the unit hydrograph developed for respective dam site and for the free catchment between respective dam sites and weir sites to compute Direct Surface Runoff Ordinate (DSRO). A base flow at the rate of 0.15 m3/s / km2 has been added to the ordinates of the DSRO to get the design flood hydrograph ordinates.

5.14.2.4 Flood Hydrograph at Barrage Sites

Outflow flood hydrograph at the respective dam sites has been routed using Muskingum method and routed flood hydrograph has been added to flood hydrograph of sub catchment between respective dam site and barrage site to assess the SPF, 500 year and 100 year return period flood for the respective weir site.

260 The standard project flood hydrograph (SPF), 500 year return period flood and 100 year return period flood hydrograph for the Paikhed barrage are given in Fig 5.97 to 5.99 respectively. The peaks of SPF, 500 year return period and 100 year return period flood at Paikhed barrage site works out as 4596 cumec, 2819 cumec and 2247 cumec respectively.

Fig - 5.97: SPF Flood Hydrograph at Paikhed Barrage

Fig 5.98: 500 year Return Period Flood Hydrograph at Paikhed Barrage

261 Fig - 5.99: 100 year Return Period Flood Hydrograph at Paikhed Barrage The standard project flood hydrograph (SPF), 500 year return period flood and 100 year return period flood hydrograph for the Chasmandva Barrage are given in Fig - 5.100 to 5.102 respectively. The peaks of SPF, 500 year return period and 100 year return period flood at Chasmandva Barrage site works out as 3213 cumec, 1961 cumec and 1572 cumec respectively.

Fig - 5.100: SPF Flood Hydrograph at Chasmandva Barrage

262 Fig-5.101: 500 year Return Period Flood Hydrographat Chasmandva Barrage

Fig - 5.102: 100 year Return Period Flood Hydrograph at Chasmandva Barrage

5.14.2.5 Conclusion

The peaks of SPF, 500 year return period flood and 100 year return period flood as estimated at Paikhed and Chasmandva barrages sites are given in Table 5.47:

263 The storm event of July 1941 centered at Dharampur appears to be very severe event and consequently the estimate of SPS and SPF appears to be very high. Accordingly it is proposed to adopt 500 year return period flood as check flood for the Barrage.

Table 5.47 SPF /500 Year and 100 year Return Period Flood at Various Barrage Sites

Sl. Flood Barrage sites No. Paikhed Chasmandva 1 SPF 4596 3213 2 500 year Return Period 2819 1961 Flood (Check Flood) 3 100 year Return Period 2247 1572 Flood (Design Flood)

5.14.3 Tail Water Rating Curves

Dam toe power houses are proposed at Paikhed, Chasmandva, Chikkar, Dabdar and Kelwan dam sites. One canal power house is also proposed on canal fall of feeder canal originating from Kelwan dam. One tail race channel is proposed at the exit of each power house to carry the waters to the respective river course after power generation. G & D observations very close to dam site could not be carried out due to public hindrance and the G & D sites for which the observations carried out are lying far away from dam sites. Thus, the data available from the Nanipalsan G & D site located on Damanganga river just downstream of proposed Bhugad dam is found to be appropriate to consider for generation of tail water rating curve as topographical and physical characteristics of the G & D site and dam sites proposed in Par-Tapi-Narmada are similar. Data for Tail water rating curve in the down-stream of various dam sites are furnished at Table 5.48 and the tail water rating curves are at Fig 5.103 to 5.107.

Table 5.48 Tail Water Rating Curve at various Dam Sites

Sl. Paikhed Chasmandva Chikkar No.

264 Leve Discharg Level Discharg Level Discharge l (m) e (m) e (m) (cumec) (cumec) (cumec) 1 158 0 166.92 0 152.45 0 2 159 25 167.92 50 153.45 50 3 160 80 168.92 95 154.45 95 4 161 125 169.92 135 155.45 200 5 162 300 170.92 262 156.45 425 6 163 851 171.92 512 157.45 600 7 164 1355 172.92 872 158.45 800 8 165 1909 173.92 1667 159.45 1020 9 166 2566 174.92 2813 160.45 1600 10 167 3479 175.92 4324 161.45 2244 11 168 4674 162.45 3405 12 169 6573 163.45 5082 13 170 9335 164.45 7709

Table 5.48 (contd…) Tail Water Rating Curve of various Dam Sites

Sl. Dabdar Kelwan No. Level Discharg Level Discharg (m) e (m) e (cumec) (cumec) 1 110.38 0 115 0 2 111.38 50 116 50 3 112.38 95 117 95 4 113.38 202 118 163 5 114.38 459 119 566 6 115.38 822 120 1267 7 116.38 1168 121 2206 8 117.38 1623 122 3334 9 118.38 2000 123 4742 10 119.38 2650 124 5900 11 120.38 3910 125 7199 12 121.38 5500 126 8100 13 122.38 7052 127 11342

265 Fig 5.103: Tail Water Rating Curve of Paikhed Dam Power House

Fig 5.104: Tail Water Rating Curve of Chasmandva Dam Power House

266 Fig 5.105: Tail Water Rating Curve of Chikkar Dam Power House

Fig 5.106: Tail Water Rating Curve of Dabdar Dam Power House

267 Fig 5.107: Tail Water Rating Curve of Kelwan Dam Power House

5.15 Studies for Design of Drainage in the Command Area

The link canal will cross number of natural streams/ river in its en- route. The natural course of these streams/ river may be affected due to canal crossing. Suitable cross drainage works will be provided at each of such crossings. These cross drainage works will be so designed that they do not hamper the width and course of the river streams and therefore, minimized the siltation problem which may arise at the crossings. Thus, little impacts on the drainage aspects are anticipated. The cross drainage structures will take care of any adverse impacts in the command area

5.16 Studies for Determination of Levels for Locating Structures on Outlets 5.16.1 Location of Structures

Par–Tapi–Narmada link project envisages construction of following components:

268 1. A composite embankment (concrete faced rock fill) - cum - concrete dam across river Par near village Jheri with FRL 246 m;

2. A composite embankment (concrete faced rock fill) - cum - concrete dam across river Nar (a tributary of river Par) near village Paikhed with FRL 248 m;

3. A composite embankment (concrete faced rock fill) - cum - concrete dam across river Tan (a tributary of river Auranga) near village Chasmandva with FRL 214 m;

4. A composite embankment (concrete faced rock fill) - cum - concrete dam across river Ambica near Chikkar village with FRL 210 m;

5. A composite embankment (concrete faced rock fill) - cum - concrete dam across Khapri river (a tributary of river Ambica) near village Dabdar with FRL 169 m;

6. A composite embankment (concrete faced rock fill) - cum - concrete dam across Purna river near village Kelwan with FRL 164 m;

7. Two Barrages; one each in the downstream of Paikhed and Chasmandva dam sites;

8. A tunnel of about 12.7 km long inter connecting Jheri and Paikhed reservoirs;

9. Six power houses one each at the toe of Paikhed, Chasmandva, Chikkar, Dabdar and Kelwan dams and one power house at the drop of feeder pipelines connecting Kelwan reservoir with Link canal;

10.A link canal 406.116 km long (including feeder pipelines of total length 37.075 km and 5 Nos. of tunnels of total length 1.15 km along the canal) off taking from Paikhed Barrage at FSL 142.800 m and connecting all the reservoirs (proposed in Par-Tapi-Narmada link project) in its en- route to carry water upto existing Miyagam Branch Canal of Narmada Canal System (target command area);

11.Cross Drainage / Cross Masonry works including regulators, escapes,

269 road/ railway bridges (469 No).

5.16.2 Location of Outlets

The Par-Tapi-Narmada link will provide irrigation in its en-route in the new areas to its left, to the tribal areas lying right side of link canalby lift, take over the command area of five proposed projects of Government of Gujarat(Khuntali, Ugta, Sidhumber, Khata Amba and Zankhari), and take over the part command area of the existing Miyagam Branch Canal of Narmada Canal System. The link canal will terminate at RD 16.70 km of Miyagam Branch Canal. In addition, the village tanks/check dams in the benefitted area will be filled and drinking water needs of the people will be met.Suitable outlets are provided in Par-Tapi-Narmada link canal to cater the needs of en-route area and location and area covered are given in Tables 5.49, 5.50and 5.51.

Table - 5.49 Locations of Outlets and En-route Command Area Benefitted under Par-Tapi Reach of Par-Tapi-Narmada Link Project

Outlet Topo Location En-route FSL at En-route Dis- Taluka Distric No/ sheet of main command head of Irrigation charge t branch no. canal RD area (ha) Branch Demand (cumec) canal in km. Gross CCA canal (MCM) 1 46 76.45 250 233 126.597 1.50 0.10 Vansda Navsari 2 H/6 81.20 70 69 125.593 0.43 0.03 Vansda Navsari 3 82.35 3240 2448 125.090 15.32 1.02 Vansda Navsari 4 46 99.00 222 222 121.140 1.38 0.10 Vansda Navsari 5 H/5 103.85 314 312 120.123 1.98 0.13 Vansda Navsari 6 108.49 208 201 119.036 1.25 0.08 Vyara Tapi 7 111.82 174 167 118.471 1.05 0.06 Vyara Tapi 8 112.45 122 118 118.242 0.74 0.05 Vyara Tapi 9 115.05 4071 3796 117.487 23.65 1.57 Vyara Tapi 10 118.36 163 163 116.783 1.02 0.06 Vyara Tapi 11 122.02 38 36 115.756 0.26 0.02 Vyara Tapi

270 12 46 125.33 37 34 115.152 0.26 0.02 Vyara Tapi 13 G/8 133.09 64 47 113.818 0.29 0.02 Vyara Tapi 14 137.61 185 165 113.095 1.04 0.06 Vyara Tapi 15 143.53 100 98 111.830 0.62 0.04 Vyara Tapi 16 46 159.86 438 421 109.138 2.62 0.18 Songadh Tapi 17 G/12 161.94 146 139 108.663 0.86 0.06 Songadh Tapi 18 165.94 493 428 107.863 2.66 0.18 Songadh Tapi 19 169.42 218 205 107.043 1.28 0.09 Songadh Tapi 20 171.99 288 253 106.551 1.55 0.10 Songadh Tapi 21 174.27 134 133 106.012 0.82 0.06 Songadh Tapi 22 177.12 473 412 105.347 2.56 0.18 Songadh Tapi Total 11448 10100 63.13

Tapi-Narmada Reach

Outlet Topo Location En-route FSL at En-route Dis- Taluka District No/ sheet of main command head of Irrigatio charge branch no. canal area (ha) Branch n (cumec) canal RD in Gross CCA canal Demand km. (MCM) 1 46 1.41 101 92 81.650 0.55 0.04 Songadh Tapi 2 G/11 3.70 171 168 81.267 1.05 0.06 Songadh Tapi 3 6.87 109 107 80.797 0.68 0.04 Songadh Tapi 4 7.69 120 115 80.709 0.71 0.05 Songadh Tapi 5 11.49 125 121 80.277 0.77 0.05 Songadh Tapi 6 46 15.72 151 150 79.750 0.94 0.06 Songadh Tapi 7 G/7 17.41 240 234 79.481 1.49 0.10 Songadh Tapi 8 32.01 324 316 77.761 1.98 0.13 Mandvi Surat 9 33.33 436 408 77.629 2.54 0.17 Mandvi Surat 10 34.11 176 170 77.551 1.06 0.06 Mandvi Surat 11 37.71 430 413 77.090 2.59 0.18 Mandvi Surat 12 43.22 138 130 76.384 0.82 0.06 Mandvi Surat 13 46 47.79 615 612 76.127 3.83 0.26 Mandvi Surat 14 G/3 49.56 3570 3365 75.698 21.05 1.39 Mandvi Surat 15 51.04 13347 11457 75.550 71.61 4.74 Mandvi Surat 16 55.79 817 756 75.023 4.74 0.31 Mandvi Surat 17 57.09 600 589 74.892 3.68 0.25 Mandvi Surat 18 46 60.69 5003 4061 74.428 25.38 1.69 Mangrol Surat 19 G/7 64.37 2636 2386 73.946 14.90 0.98 Mangrol Surat 20 69.15 1493 1433 73.261 8.94 0.59 Mangrol Surat 21 46 71.48 306 295 72.976 1.84 0.12 Valia Bharuc G/6 h 22 82.17 26437 22442 71.143 140.24 9.30 Valia Bharuc h Total 57345 49820 311.39

271 The location of branch canals/outlets and area covered in respect of five proposed projects of Government of Gujarat taken over by Par-Tapi- Narmada link canal are furnished in Table – 5.50:

Table - 5.50 Location of Branch Canals/Outlets and Command Area of Five Proposed Projects Benefitted Under Par-Tapi-Narmada Link Project Outlet Topo Location En-route FSL at En-route Discharge Taluk District No./ sheet of Main Command head of Irrigati (cumec) a Branch no. Canal Area (ha) Branch on Canal RD in canal Deman km. (m) d (MCM) CCA AI I Par-Tapi reach A Khuntali 1 46 31.300 3162 3162 135.507 20 1.26 Dharam Valsad H/3 pur B Ugta 1 46 42.75 2080 2080 131.967 13 0.82 Dharam Valsad H/6 pur 2 46 46.08 2883 2883 132.40 18 1.14 Dharam Valsad H/6 pur C Sidhumber 1 46 48.78 11073 11073 131.956 69 4.35 Dharam Valsad H/6 pur 2 46 49.63 6368 6368 131.643 40 2.52 Dharam Valsad H/6 pur D Khata Amba 1 46 82.44 2032 2032 124.780 13 0.82 Vansada Navsari H/6 2 46 89.09 709 709 123.570 4 0.25 Vansada Navsari H/6 E Zankhari 1 46 137.93 8817 8817 112.758 55 3.47 Vyara Tapi G/12 2 46 141.03 8437 8437 112.174 53 3.34 Songadh Tapi G/12 Total 45561 45561 285

The location of Pump Houses proposed to irrigate tribal areas lying Right side of Link canal by lift, proposed irrigation and water demand are furnished in Table – 5.51:

Table - 5.51 Location of Pump Houses proposed to irrigate tribal areas lying Right side of Link Canal by lift and Command Area under Par-Tapi- Narmada Link Project 272 Outlet Topo Location En-route FSL of En-route Discharge Taluka District No./ sheet of Main Command Area MainCan Irrigatio (cumec) no. Canal (ha) al n RD in (m) Demand km. (MCM) CCA AI I Par-Tapi reach A Area-1 1 46 113.60 900 900 117.958 3.5 0.29 Vyara Tapi H/5 B Area-2 46 141.60 13100 13100 112.206 50.0 4.27 Songadh Tapi G/12

II Tapi-Narmada reach C Area-3 1 46 38.000 1200 1200 77.010 4.6 0.39 Mandvi Surat G/7 2 46 44.700 4400 4400 76.236 16.9 1.43 Mangrol Surat G/7 3 46 59.700 900 900 74.580 3.5 0.29 Mangrol Surat G/7 D Area-4 1 68.60 15700 15700 73.316 60 5.09 Mangrol Surat Total 36200 36200 138.0

5.17 Simulation Studies of the Reservoirs

The multi reservoir simulation studies carried out with the 6 reservoirs (Jheri, Paikhed, Chasmandva, Chikkar, Dabdar and Kelwan), 2 barrages (Paikhed and Chasmandva) and existing Ukai reservoir for Par- Tapi-Narmada link project using the Simulation software programme exclusively developed for Par-Tapi-Narmada link in C++ language by the NWDA.

Simulation study is appended as Annexures 5.20 in Volume-II. The Broad Criteria adopted while carrying out the Simulation studies are as follows:

5.17.1 Broad Criteria

273  The simulation studies have been carried out on monthly basis for a period of 30 years from 1976 to 2006.  The minimum flows required for d/s environmental uses are considered as 10% of the average annual lean season natural flow during October to May.  The initial storage at the beginning of the simulation (June, 1976) is considered with 10% of the live storage for each reservoir.  Upto 10% deficit in meeting a demand on annual basis is considered to be success, presuming the system to be resilient in coping with such shortage.  The Storage capacities at different elevations after 50 years of sedimentation have been considered for each reservoir.  No salinity control requirements are considered in the study assuming that the demand would be met from the yields of downstream catchments of proposed reservoirs and existing Ukai project.

5.17.2 Computation of Net Inflows into Reservoirs and Barrages

The hydrological studies for Jheri, Paikhed, Chasmandva, Chikkar, Dabdar and Kelwan reservoirs have been carried out by Central Water Commission, New Delhi and submitted Report on Water Availability Study of Par-Tapi-Narmada Link Project (March, 2012).

Therefore, the respective month-wise gross yields for monsoon period (June to Sept) are considered as per the studies conducted by Central Water Commission from which corresponding annual u/s utilizations (existing, ongoing and proposed) are deducted to arrive at net inflows at these reservoirs. The year-wise gross non-monsoon flows as assessed by Central Water Commission have been distributed into monthly flows in proportion to the observed flow data available at the nearest G & D site on the respective rivers. The list of proposed storage Dams / barrages and G & D site on various rivers are given in Table 5.52:

Table 5.52 Proposed Storage Dams / Barrages and G & D Site OnVarious Rivers

274 Sl. Dam / Located G & D Site Location of Period of Yields No Barrage on River / (for Yield Proposed Availabil Developed Tributary Analysis) Dam / ity of for the Barrage Data Period 1 Jheri dam Par Nanivahiyal U/s of G 1966 to 1975 to & D site 2004 2006 2 Paikhed Par / Nar Nanivahiyal U/s of G & 1966 to 1975 to dam D site 2004 2006 3 Paikhed Par / Nar Nanivahiyal U/s of G & 1966 to 1975 to barrage D site 2004 2006 4 Chasmand Auranga / Amba U/s of G & 1962 to 1975 to va dam Tan D site 2004 2006 5 Chasmand Auranga / Amba U/s of G & 1962 to 1975 to va Tan D site 2004 2006 barrage 6 Chikkar Ambica Waghai* U/s of G & *Kudkas 1975 to dam D site site 1980 2006 to 2006 *Rainfall-Run off model at Kudkas G & D site used for yield analysis instead of Waghai G & D site 7 Dabdar Ambica / Kudkas D/s of G 1980 to 1975 to dam Khapri & D site 2006 2006 8 Kelwan Purna Kalibel D/s of G 1962 to 1975 to dam & D site 2000 2006 9 Ukai Tapi river Inflows in to Ukai 1973 to 1975 to existing reservoir 1998 2006 dam

The methodology for arriving the net inflows at Jheri, Paikhed, Chasmandva, Chikkar, Dabdar and Kelwan and Ukai reservoirs are furnished in the following paragraphs.

(I) Jheri Reservoir

The proposed Jheri dam site is located upstream of the Nanivahiyal G & D site across Par river and the discharge data of Nanivahiyal G & D site is available from 1966 to 2004. The same has been used for developing the monthly and monsoon rainfall-runoff modeling at Nanivahiyal G & D site. Using the Rainfall-Runoff model developed at Nanivahiyal G & D site the monthly yield series at Jheri dam site for the monsoon period from 1975- 2006 has been generated. The non-monsoon yield is distributed in to non- monsoon monthly yields in the proportion of the observed flow at Nanivahiyal G & D site. 275 The net yield has been worked out after subtracting all the upstream utilisation and adding the regeneration. The regeneration for major and medium Irrigation projects has been considered as 10% while the same minor Irrigation projects has been neglected. The regeneration from domestic and industrial requirement met from surface water has been considered as 80%.

Monthly inflows in to Jheri reservoir as worked out above pattern for the period from 1975 to 2006 are given Table 5.53.

Table 5.53 Monthly Net Inflows at Jheri Dam Site from 1975-76 to 2006-07 (MCM) Year Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May 1975 15.24 43.98 219.71 143.30 26.7 5.32.9 1.5 0.6 0.4 0.0 0.0 1976 73.05 390.19 294.06 96.75 42.8 20.5 7.7 3.0 1.4 0.2 0.0 0.0 1977 50.47 224.85 149.51121.58 27.2 11.4 6.5 2.5 0.90.0 0.0 0.0 1978 13.18 101.91 202.2089.87 15.6 11.9 6.2 2.0 0.4 0.0 0.0 0.0 1979 0.00 77.86 253.33 66.31 21.3 10.53.4 0.00.00.0 0.0 0.0 1980 41.81 121.75 230.83 96.17 31.8 8.03.7 0.00.00.0 0.0 0.0 1981 13.78 378.82 187.64145.04 63.6 0.00.0 0.50.20.1 0.0 0.0 1982 0.00 69.58 237.73 72.46 20.2 9.12.9 1.00.30.1 0.0 0.0 1983 0.00 156.24 315.80123.87 45.3 5.41.5 0.50.20.0 0.0 0.0 1984 5.89 96.80 159.66 75.56 26.0 2.70.9 0.40.00.0 0.0 0.0 1985 0.00 81.80 140.07 33.77 17.8 2.81.4 0.60.10.0 0.0 0.0 1986 6.78 74.57 108.64 24.55 13.8 3.11.4 0.60.00.0 0.0 0.0 1987 0.00 63.13 116.76 32.83 11.2 6.01.7 0.00.00.0 0.0 0.0 1988 6.93 220.26 113.48136.69 38.0 3.40.6 0.30.00.0 0.0 0.0 1989 0.00 147.58 105.26 68.01 25.9 1.80.7 0.10.00.0 0.0 0.0 1990 15.32 289.68 386.35151.76 67.3 4.5 2.5 0.50.00.0 0.0 0.0 1991 9.13 102.53 259.83151.42 35.78.91.7 0.00.00.0 0.0 0.0 1992 11.93 85.75 261.28182.02 42.0 5.01.0 0.00.00.0 0.0 0.0 1993 6.72165.46 75.06165.55 30.5 4.51.5 0.20.00.0 0.0 0.0 1994 71.73322.28 228.45165.75 48.1 18.53.3 0.00.00.0 0.0 0.0 1995 0.00 90.20 54.39 80.64 17.6 2.00.4 0.00.00.0 0.0 0.0 1996 4.92 113.43 157.02 74.54 23.0 6.81.1 0.10.00.0 0.0 0.0 1997 4.80 101.78 227.5361.92 22.1 8.04.0 1.10.00.0 0.0 0.0 1998 7.27 41.38 155.50165.36 24.6 6.31.7 0.20.00.0 0.0 0.0 1999 29.44 165.80 79.82 92.29 31.3 1.00.2 0.00.00.0 0.0 0.0 2000 0.00 64.69 59.30 35.45 10.3 1.20.3 0.71.60.0 0.0 0.0 2001 29.27 65.71 118.69 60.05 15.4 6.12.4 0.30.00.0 0.0 0.0 2002 74.57 61.97 175.9479.43 20.8 7.63.9 2.00.40.0 0.0 0.0 2003 33.60 141.82 177.3698.43 28.010.01.6 0.30.20.0 0.0 0.0 2004 15.03 45.55 459.31102.45 55.0 0.00.0 0.20.00.0 0.0 0.0 2005 113.11 180.22 194.83276.53 54.3 9.23.2 0.80.30.0 0.0 0.0 2006 10.43 282.60 439.80101.61 59.310.03.5 0.90.30.0 0.0 0.0

(II) Paikhed Reservoir

The proposed Paikhed dam site is located across Nar river, a tributary of Par river. The Discharge data of Nanivahiyal G & D site is available

276 from 1966 to 2004. The same has been used for developing the monthly and monsoon rainfall-runoff modeling at Nanivahiyal G & D site. Using the Rainfall-Runoff model developed at Nanivahiyal G & D site the monthly yield series at Paikhed dam site for the monsoon period from 1975 to 2006 has been generated.

The net yield has been worked out after subtracting all the upstream utilisation and adding the regeneration. The regeneration for major and medium Irrigation projects has been considered as 10% while the same minor Irrigation projects has been neglected. The regeneration from domestic and industrial requirement met from surface water has been considered as 80%.

Monthly inflows in to Paikhed reservoir as worked out above pattern for the period from 1975 to 2006 are given Table 5.54:

Table 5.54 Monthly Net Inflows at Paikhed Dam Site from 1975-76 to 2006-07 (MCM)

Year Jun Jul Aug Sept Oct Nov Dec Jan Feb Mar Apr May 1975 11.2 24.4145.593.717.43.51.9 1.0 0.4 0.2 0.0 0.0 1976 45.6294.8212.085.532.015.35.8 2.3 1.1 0.2 0.0 0.0 1977 48.2152.2117.5118.921.89.25.2 2.0 0.7 0.0 0.0 0.0 1978 13.1104.0176.162.713.710.45.4 1.7 0.4 0.0 0.0 0.0 1979 0.046.8178.4 48.514.77.22.4 0.0 0.0 0.0 0.0 0.0 1980 20.3 82.1168.6 56.821.35.32.5 0.0 0.0 0.0 0.0 0.0 1981 6.7303.6151.4101.349.40.0 0.0 0.4 0.1 0.0 0.0 0.0 1982 3.4 96.1205.0 66.219.78.92.9 1.0 0.3 0.1 0.0 0.0 1983 0.0 106.5257.6137.8 38.2 4.51.3 0.5 0.1 0.0 0.0 0.0 1984 5.2 71.7 100.7 49.217.41.80.6 0.2 0.0 0.0 0.0 0.0 1985 0.0 80.6 97.8 16.913.62.21.1 0.4 0.1 0.0 0.0 0.0 1986 2.5 56.9 63.8 15.28.92.00.9 0.4 0.0 0.0 0.0 0.0 1987 0.0 53.3 78.9 20.6 8.14.31.2 0.0 0.0 0.0 0.0 0.0 1988 0.0 117.2 61.2124.824.22.20.4 0.2 0.0 0.0 0.0 0.0 1989 0.0 100.0 78.5 36.4 17.31.20.5 0.1 0.0 0.0 0.0 0.0 1990 6.0 51.6 137.1 73.9 21.41.40.8 0.2 0.0 0.0 0.0 0.0 1991 6.2 92.0 112.8 27.2 16.34.10.8 0.0 0.0 0.0 0.0 0.0 1992 9.6 52.7 118.8 94.7 21.42.50.50.0 0.0 0.0 0.0 0.0 1993 16.4106.2 55.6123.6 22.33.31.10.1 0.0 0.0 0.0 0.0 1994 72.2250.3164.8148.1 38.814.92.7 0.0 0.0 0.0 0.0 0.0 1995 0.0 56.0 32.3 44.1 10.41.20.20.0 0.0 0.0 0.0 0.0 1996 1.7104.6120.1 55.9 18.65.50.90.1 0.0 0.0 0.0 0.0 1997 0.0 79.7152.7 55.1 16.05.82.90.8 0.0 0.0 0.0 0.0 1998 0.0 17.7114.3117.9 16.64.21.20.1 0.0 0.0 0.0 0.0 1999 18.2156.665.9 87.6 28.00.90.20.0 0.0 0.0 0.0 0.0 2000 0.0 65.6 65.0 33.7 10.61.20.30.8 1.7 0.0 0.0 0.0 277 2001 22.8 63.6102.6 27.9 12.24.81.90.2 0.0 0.0 0.0 0.0 2002 57.9 11.1176.0 94.9 18.16.63.41.8 0.3 0.0 0.0 0.0 2003 26.8 120.2135.0 92.1 23.28.31.40.2 0.1 0.0 0.0 0.0 2004 19.5 55.1346.2 84.5 44.70.00.00.1 0.0 0.0 0.0 0.0 2005 119.2161.2152.5201.8 45.17.62.60.7 0.2 0.0 0.0 0.0 2006 1.6210.0296.2 58.6 40.36.82.30.6 0.2 0.0 0.0 0.0

(III) Paikhed Barrage

The catchment area upto Paikhed barrage is 315 km2. The catchment area between Paikhed dam and Paikhed barrage is 12 km2. No inflow has been considered from the free catchment between Paikhed dam and Paikhed barrage.

(IV) Chasmandva Reservoir:

The proposed Chasmandva dam site is located u/s of the Amba G & D site across Tan river a tributary of Auranga river and discharge data of Amba G & D site is available from 1962 to 2004. The monsoon discharge data extended for the years 2005 and 2006 and is taken as the average of monsoon data pertaining to 1975 to 2004. For non-monsoon period, monthly flow data is available from 1998-99 to 2006-07. The non monsoon monthly flows from 1975-76 to 1997-98 are worked out based on the average of available data. The monsoon monthly yield series at Chasmandva dam site has been developed for the period from 1975 to 2006 using rainfall runoff models developed at Amba G & D site. The non-monsoon yield is distributed in to non-monsoon monthly yields in the proportion of the observed flow at Amba G & D site.

The net yield has been worked out after subtracting all the upstream utilisation and adding the regeneration. The regeneration for major and medium Irrigation projects has been considered as 10% while the same minor Irrigation projects has been neglected. The regeneration from domestic and industrial requirement met from surface water has been considered as 80%.

Monthly inflows in to Chasmandva reservoir as worked out above pattern for the period from 1975 to 2006 are given Table 5.55:

Table 5.55 Monthly Net Inflows at Chasmandva Dam Site 278 from 1975-76 to 2006-07 (MCM)

Year Jun Jul Aug Sept Oct Nov Dec Jan Feb Mar Apr May 1975 7.6 17.561.824.25.80.5 0.1 0.0 0.0 0.0 0.0 0.0 1976 11.1 88.0 69.925.410.10.9 0.3 0.0 0.0 0.0 0.0 0.0 1977 12.440.337.740.16.80.6 0.2 0.0 0.0 0.0 0.0 0.0 1978 7.2 29.053.411.45.20.5 0.1 0.0 0.0 0.0 0.0 0.0 1979 0.07.450.25.83.30.3 0.1 0.0 0.0 0.0 0.0 0.0 1980 6.7 25.2 56.37.24.90.4 0.1 0.0 0.0 0.0 0.0 0.0 1981 0.464.8 39.128.16.90.6 0.2 0.0 0.0 0.0 0.0 0.0 1982 0.0 13.5 47.87.23.60.3 0.1 0.0 0.0 0.0 0.0 0.0 1983 0.016.052.018.74.50.4 0.1 0.0 0.0 0.0 0.0 0.0 1984 1.127.1 31.38.93.60.3 0.1 0.0 0.0 0.0 0.0 0.0 1985 0.026.431.32.13.10.3 0.1 0.0 0.0 0.0 0.0 0.0 1986 2.125.823.30.02.70.2 0.1 0.0 0.0 0.0 0.0 0.0 1987 0.013.521.90.01.80.2 0.0 0.0 0.0 0.0 0.0 0.0 1988 0.0 44.517.232.94.90.4 0.1 0.0 0.0 0.0 0.0 0.0 1989 0.021.727.33.82.70.2 0.1 0.0 0.0 0.0 0.0 0.0 1990 0.76.435.816.93.10.3 0.1 0.0 0.0 0.0 0.0 0.0 1991 0.027.427.12.63.00.3 0.1 0.0 0.0 0.0 0.0 0.0 1992 7.613.231.431.44.30.4 0.1 0.0 0.0 0.0 0.0 0.0 1993 23.241.714.349.86.70.6 0.2 0.0 0.0 0.0 0.0 0.0 1994 21.655.853.734.98.60.8 0.2 0.0 0.0 0.0 0.0 0.0 1995 0.022.46.38.71.90.2 0.1 0.0 0.0 0.0 0.0 0.0 1996 0.026.735.56.23.60.3 0.1 0.0 0.0 0.0 0.0 0.0 1997 0.025.933.89.73.60.3 0.1 0.0 0.0 0.0 0.0 0.0 1998 0.010.134.429.53.01.0 0.3 0.0 0.0 0.0 0.0 0.0 1999 6.538.313.426.54.20.6 0.1 0.0 0.0 0.0 0.0 0.0 2000 0.027.524.84.82.70.3 0.3 0.0 0.0 0.0 0.0 0.0 2001 6.621.633.41.03.00.5 0.2 0.0 0.0 0.0 0.0 0.0 2002 13.5 0.0 45.917.54.4 0.0 0.0 0.0 0.0 0.0 0.0 0.0 2003 7.8 38.7 31.417.75.5 0.0 0.0 0.0 0.0 0.0 0.0 0.0 2004 7.4 15.1 96.512.77.6 0.0 0.0 0.0 0.0 0.0 0.0 0.0 2005 41.542.643.935.99.5 0.0 0.0 0.0 0.0 0.0 0.0 0.0 2006 0.8 50.681.810.68.3 0.0 0.0 0.0 0.0 0.0 0.0 0.0

(V) Chasmandva Barrage

The proposed Chasmandva barrage site is located u/s of the Amba G & D site across Tan river a tributary of Auranga river. The catchment area upto Chasmandva dam is 89.25 km2 and the catchment area between Chasmandva dam and Chasmandva barrage is 41 km2. No inflow has been considered from the free catchment between Chasmandva dam and Chasmandva barrage.

(VI) Chikkar Reservoir

The proposed Chikkar dam site is located u/s of the Wagai G & D site across Ambica river. The discharge data of Wagai G & D site is available from 1974 to 1978 and 1999 to 2006 and data is not sufficient for developing the rainfall runoff model. The data at Kudkas

279 G & D site located across Khapri river, a tributary of Ambica river is available from 1980 to 2006. The rainfall runoff models developed at Kudkas G & D site has been used to generate the monthly monsoon yields series at proposed Chikkar dam site for the period from 1975 to 2006. The non-monsoon yield is distributed in to non-monsoon monthly yields in the proportion of the observed flow at Kudkas G & D site.

The net yield has been worked out after subtracting all the upstream utilisation and adding the regeneration. The regeneration for major and medium Irrigation projects has been considered as 10% while the same minor Irrigation projects has been neglected. The regeneration from domestic and industrial requirement met from surface water has been considered as 80%.

Monthly inflows in to Chikkar reservoir as worked out above pattern for the period from 1975 to 2006 are given Table 5.56:

Table 5.56 Monthly Net Inflows at Chikkar Dam Site from 1975-76 to 2006-07 (MCM)

Year Jun Jul Aug Sept Oct Nov Dec Jan Feb Mar Apr May 1975 0.0 34.7126.7 75.5 19.12.50.4 0.0 0.0 0.0 0.0 0.0 1976 30.0 124.1 195.176.334.34.50.7 0.1 0.0 0.0 0.0 0.0 1977 27.2 65.3 85.687.221.42.80.4 0.0 0.0 0.0 0.0 0.0 1978 6.7 35.8 111.9 35.315.32.00.3 0.0 0.0 0.0 0.0 0.0 1979 0.0 23.0 104.429.812.71.70.3 0.0 0.0 0.0 0.0 0.0 1980 9.2 15.0 105.5 17.310.52.50.7 0.0 0.0 0.0 0.0 0.0 1981 0.0 84.1 81.4 77.122.60.00.0 0.0 0.0 0.0 0.0 0.0 1982 0.1 17.4 89.123.08.72.60.9 0.0 0.0 0.0 0.0 0.0 1983 0.0 22.3 131.180.419.91.40.5 0.0 0.0 0.0 0.0 0.0 1984 0.0 48.1 78.960.615.81.40.0 0.3 0.0 0.0 0.0 0.0 1985 0.0 66.9 70.617.1 10.5 2.81.1 0.0 0.0 0.0 0.0 0.0 1986 1.3 44.4 86.328.0 13.51.40.0 0.0 0.0 0.0 0.0 0.0 1987 0.0 12.4 75.2 10.45.63.60.0 0.0 0.0 0.0 0.0 0.0 1988 0.0 85.2 59.3136.625.21.00.0 0.0 0.0 0.0 0.0 0.0 1989 0.0 25.8 70.517.49.31.20.0 0.0 0.0 0.0 0.0 0.0 1990 0.0 21.1110.245.6 4.610.81.0 0.0 0.0 0.0 0.0 0.0 1991 12.2 35.382.49.4 10.92.1 0.0 0.0 0.0 0.0 0.0 0.0 1992 7.2 18.081.974.5 15.01.9 0.0 0.0 0.0 0.0 0.0 0.0 1993 3.055.460.0126.420.32.5 0.0 0.0 0.0 0.0 0.0 0.0 1994 84.3118.1123.7126.539.8 2.4 0.0 0.0 0.0 0.0 0.0 0.0 1995 0.0 25.667.338.2 10.81.4 0.0 0.0 0.0 0.0 0.0 0.0 1996 0.039.382.659.0 16.10.7 0.0 0.0 0.0 0.0 0.0 0.0 1997 0.014.8113.734.9 12.71.6 0.7 0.3 0.0 0.0 0.0 0.0 1998 0.0 28.2146.398.021.03.9 0.5 0.0 0.0 0.0 0.0 0.0 1999 15.149.652.060.7 15.01.3 0.2 0.0 0.0 0.0 0.0 0.0 2000 2.552.263.716.68.83.2 0.5 0.0 0.0 0.0 0.0 0.0 2001 21.7 59.2116.220.9 16.63.0 0.7 0.0 0.0 0.0 0.0 0.0 2002 40.2 0.0108.574.9 14.84.8 1.3 0.0 0.0 0.0 0.0 0.0 2003 31.187.6117.681.326.82.2 0.6 0.0 0.0 0.0 0.0 0.0 2004 11.244.1269.156.729.84.0 1.7 0.0 0.0 0.0 0.0 0.0 280 2005 101.6 86.4170.1191.545.05.9 0.3 0.0 0.0 0.0 0.0 0.0 2006 2.7 150.6 284.051.734.89.61.2 0.0 0.0 0.0 0.0 0.0

(VII) Dabdar Reservoir

The proposed Dabdar dam site is located downstream of the Kudkas G & D site across Khapri river, a tributary of Ambica river. The gauge and discharge data of Kudkas G & D site are available from 1980 to 2006. The yield series at proposed Dabdar dam site has been generated from year 1980 to 2006 on catchment are proportionate basis, using observed data after duly checking the consistency. As the Rainfall is available for longer period, the same has been used to extend the yield series for 1975 to 1979 using Rainfall-Runoff model developed at Kudkas G & D site. The non-monsoon yield at Dabdar dam site is distributed in to non-monsoon monthly uields in the proportion of the observed flow at Kudkas G & D site.

The net yield has been worked out after subtracting all the upstream utilisation and adding the regeneration. The regeneration for major and medium Irrigation projects has been considered as 10% while the same minor Irrigation projects has been neglected. The regeneration from domestic and industrial requirement met from surface water has been considered as 80%.

Monthly inflows in to Dabdar reservoir as worked out above pattern for the period from 1975 to 2006 are given Table 5.57:

Table 5.57 Monthly Net Inflows at Dabdar Dam Site from 1975-76 to 2006-07 (MCM)

Year Jun Jul Aug Sept Oct Nov Dec Jan Feb Mar Apr May 1975 0.0 46.8186.8120.228.63.80.6 0.0 0.0 0.0 0.0 0.0 1976 62.3232.7340.9124.561.48.11.2 0.1 0.0 0.0 0.0 0.0 1977 53.4 115.1134.493.432.04.20.6 0.1 0.0 0.0 0.0 0.0 1978 8.147.6154.648.820.92.80.4 0.0 0.0 0.0 0.0 0.0 1979 0.0 39.5160.053.920.52.70.4 0.0 0.0 0.0 0.0 0.0 1980 1.239.5128.550.66.21.5 0.4 0.0 0.0 0.0 0.0 0.0 1981 12.0219.2149.874.627.20.00.0 0.0 0.0 0.0 0.0 0.0 1982 0.8 35.0 166.7 39.4 7.6 2.20.70.0 0.0 0.0 0.0 0.0 1983 0.041.9235.0145.7 75.9 5.41.80.00.00.0 0.0 0.0 1984 1.2 135.3191.1 121.3 30.0 2.7 0.00.50.00.0 0.0 0.0 1985 0.0 81.7147.3 21.8 7.9 2.00.80.00.00.0 0.0 0.0 1986 1.383.7131.127.8 4.1 0.4 0.00.00.00.0 0.0 0.0 1987 0.035.265.6 17.42.3 1.50.00.00.00.0 0.0 0.0 1988 5.4 116.7 89.5 165.4 49.6 1.9 0.00.00.00.0 0.0 0.0 281 1989 0.1 58.0114.832.7 5.6 0.7 0.00.00.00.0 0.0 0.0 1990 1.8 22.8122.0 67.5 0.7 1.7 0.20.00.00.0 0.0 0.0 1991 4.550.9149.9 52.3 4.7 0.9 0.00.00.00.0 0.0 0.0 1992 13.727.6110.3 101.8 9.2 1.2 0.00.00.00.0 0.0 0.0 1993 4.9110.4 46.9 102.3 53.6 6.60.00.00.00.0 0.0 0.0 1994 183.6417.5354.6 309.6 16.4 1.00.00.00.00.0 0.0 0.0 1995 0.0 94.0 107.7 130.5 37.7 4.80.00.00.00.0 0.0 0.0 1996 1.0 71.5156.4 114.8 11.3 0.50.00.00.00.0 0.0 0.0 1997 0.7 50.2261.3 79.1 8.5 1.10.40.20.00.0 0.0 0.0 1998 1.5 63.8282.7239.4 56.810.41.30.00.00.0 0.0 0.0 1999 16.0 173.3 162.3 98.2 150.3 13.4 2.10.20.00.0 0.0 0.0 2000 0.0 93.6 65.6 54.9 22.2 8.2 1.30.00.00.0 0.0 0.0 2001 21.3 163.7 189.3 50.2 31.5 5.7 1.30.00.00.0 0.0 0.0 2002 83.0 82.9 217.9 218.8 11.1 3.61.00.00.00.0 0.0 0.0 2003 50.4 118.9 215.7 151.0 60.8 5.11.30.00.00.0 0.0 0.0 2004 13.7 35.5 345.3 56.5 48.8 6.5 2.70.00.00.0 0.0 0.0 2005 101.1 153.1 149.6 135.7 68.3 8.90.50.00.00.0 0.0 0.0 2006 0.0 140.8 226.7 79.3 51.014.11.70.00.00.0 0.0 0.0

(VIII) Kelwan Reservoir

The proposed Kelwan dam site is located downstream of the Kalibel G & D site across Purna river. The gauge and discharge data of Kalibel G & D site are available from 1962 to 2000 except for the years 1979, 1980, 1991, 1992, 1993, 1994, 1995, 1996 and 1999. The yield series at Kelwan dam site has been generated from year 1975 to 2000 on catchment area proportionate basis, using observed data after duly checking the consistency. The inconsistence data and gaps have been filled by using Rainfall-Runoff models. The yield series has been further extended beyond year 2000 using Rainfall-Runoff models. The non-monsoon yield at Kelwan dam site is distributed in to non-monsoon monthly yields in the proportion of the observed flow at Kalibel G & D site.

The net yield has been worked out after subtracting all the upstream utilisation and adding the regeneration. The regeneration for major and medium Irrigation projects has been considered as 10% while the same minor Irrigation projects has been neglected. The regeneration from domestic and industrial requirement met from surface water has been considered as 80%.

The monthly inflows in to Kelwan reservoir as worked out on the above pattern for the period from 1975 to 2006 are given in Table 5.58:

282 Table 5.58 Monthly Net Inflows at Kelwan Dam Site from 1975-76 to 2006-07 (MCM) Year Jun Jul Aug Sept Oct Nov Dec Jan Feb Mar Apr May 1975 0.0 27.3 217.5 147.0 47.1 6.2 0.9 0.1 0.0 0.0 0.0 0.0 1976 34.2 189.6 379.6 132.5 68.8 9.1 1.4 0.10.00.00.0 0.0 1977 47.5 256.9 225.5 194.3 24.6 3.3 0.50.00.00.00.0 0.0 1978 0.0 21.5 247.3 95.1 27.5 3.6 0.60.00.00.00.0 0.0 1979 9.7 27.3 272.0 24.4 31.1 4.1 0.60.00.00.00.0 0.0 1980 10.4 46.8 249.0 1.8 25.5 6.1 1.70.00.00.00.0 0.0 1981 0.0 130.6 129.9 76.2 24.9 0.0 0.00.00.00.00.0 0.0 1982 0.0 46.5 181.3 30.6 7.7 2.3 0.80.00.00.00.0 0.0 1983 0.2 36.3 323.8 116.4 74.4 5.3 1.80.00.00.00.0 0.0 1984 7.5 105.9 154.1 80.1 33.9 3.0 0.00.60.00.00.0 0.0 1985 0.0 153.5 64.2 7.6 5.1 1.3 0.50.00.00.00.0 0.0 1986 3.7 69.0 143.0 23.9 54.0 5.6 0.00.00.00.00.0 0.0 1987 0.0 124.3 77.8 15.1 1.3 0.9 0.00.00.00.00.0 0.0 1988 8.2 240.8 122.0 263.2 110.6 4.3 0.00.00.00.00.0 0.0 1989 0.0 129.0 212.0 114.1 53.0 7.0 0.00.00.00.00.0 0.0 1990 25.2 71.6 187.6 67.3 15.4 35.9 3.40.00.00.00.0 0.0 1991 17.4 61.5 172.1 4.0 23.0 4.5 0.00.00.00.00.0 0.0 1992 11.4 22.5 104.9 135.8 26.3 3.3 0.00.00.00.00.0 0.0 1993 12.1 94.5 28.0 183.3 30.5 3.8 0.00.00.00.00.0 0.0 1994 67.6 165.4 143.1 193.1 57.9 3.4 0.00.00.00.00.0 0.0 1995 0.0 126.6 18.5 109.3 24.3 3.1 0.00.00.00.00.0 0.0 1996 5.9 77.8 173.5 90.1 35.8 1.7 0.00.00.00.00.0 0.0 1997 0.0 0.0 292.5 49.0 11.8 1.5 0.60.20.00.00.0 0.0 1998 6.5 49.5 124.4 176.0 55.1 10.1 1.30.00.00.00.0 0.0 1999 17.9 58.7 44.8 165.5 28.3 2.6 0.40.00.00.00.0 0.0 2000 4.3 82.1 59.8 47.2 14.6 5.4 0.90.00.00.00.0 0.0 2001 47.2 63.4 230.2 114.6 40.2 7.3 1.60.00.00.00.0 0.0 2002 51.6 0.0 174.1 191.9 32.0 10.3 2.90.00.00.00.0 0.0 2003 28.2 147.6 177.1 166.0 50.6 4.3 1.10.00.00.00.0 0.0 2004 12.4 41.9 359.4 50.5 42.0 5.6 2.40.00.00.00.0 0.0 2005 74.9 123.4 235.8 230.1 63.0 8.2 0.40.00.00.00.0 0.0 2006 10.5 181.0 361.7 114.4 54.9 15.2 1.90.00.00.00.0 0.0

(IX) Ukai Reservoir

The existing Ukai reservoir is located across the Tapi River and is having large storage capacity which is used only as balancing reservoir for the Par-Tapi-Narmada link. The monthly inflows at Ukai reservoir are available from 1973 to 1998. The data for the remaining period from 1999- 2006 are assumed as the average of data available. The monthly inflows in to Ukai reservoir for the period from 1975 to 2006 are given in Table 5.59.The inflows and storage capacity were not utilized in study.

Table 5.59

283 Monthly Net Inflows at Ukai Reservoir from 1973-74 to 2006-07 (MCM)

Yea r Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May 197 3 138.3 4231.6 5148.1 5314.8 1548.1 526.9 148.5 148.5 128.0 107.3 143.8 165.8 197 4 175.3 1049.6 2901.8 507.5 748.0 75.7 0.0 0.0 102.9 73.4 9.5 0.0 197 200. 68. 5 425.6 1373.5 4210.2 5050.6 973.7 3 0.0 0.0 0.0 85.6 6 0.0 197 429. 176. 91. 6 1931.9 3846.1 5388.3 5061.6 243.4 7 67.8 0.0 98.7 0 4 0.0 197 221. 194. 81. 7 1649.8 1817.5 3025.5 4323.4 458.6 3 9 35.3 13.9 17.4 8 0.0 197 102. 199. 226. 18. 8 799.1 2950.6 6624.8 2637.9 200.4 77.7 4 8 193.9 8 5 0.0 197 133. 268. 188. 9 1051.7 1233.7 8840.2 1464.5 279.6 6 9 7 109.4 71.9 1.0 0.0 198 100. 0 1563.3 1022.1 4629.7 1065.4 208.6 129.4 92.0 4 38.0 11.5 0.0 0.0 198 195. 1 44.3 1766.0 3806.4 2303.9 716.8 10.1 76.7 3 133.8 76.5 0.0 0.0 198 2 479.7 1111.6 1411.4 741.6 181.2 94.0 7.7 44.7 4.8 4.4 0.0 3.5 198 177. 13. 3 99.1 1381.5 4428.8 5347.4 1822.2 0.0 0.0 75.4 127.2 0 0.0 9 198 729. 753. 4 173.8 890.9 4009.3 629.9 481.9 0 7 54.4 32.3 1.7 0.0 0.0 198 5 288.6 495.5 2020.0 251.3 283.7 39.1 0.0 0.0 0.0 0.0 0.0 0.0 198 26. 6 281.6 2046.8 4541.1 88.6 0.0 0.0 0.0 46.1 34.4 13.4 9 0.0 198 7 597.4 961.3 1121.4 216.5 5.1 0.0 0.0 0.0 0.0 0.0 0.0 0.0 198 15. 11. 8 438.3 3740.3 3448.6 5296.2 3327.4 0.0 0.0 0.0 0.0 49.7 1 0 198 27. 98. 9 258.4 2055.2 4780.1 2198.8 0.0 0.0 0.0 0.0 14.6 6.4 6 0 199 0 979.6 2746.3 7963.1 2845.3 1728.6 0.0 0.0 65.7 9.9 22.9 2.1 0.0 199 1 349.8 1523.4 2260.6 274.9 47.7 0.0 0.0 0.0 0.0 0.0 0.0 0.0 199 2 881.3 115.7 3299.8 2039.1 402.5 0.0 0.0 0.0 0.0 0.0 0.0 0.0 199 3 137.8 3150.6 1828.6 2348.4 1047.6 0.0 0.0 0.0 0.0 0.0 0.0 0.0 199 4 481.2 2891.7 4349.0 9783.7 428.1 53.2 0.0 0.0 0.0 0.0 0.0 0.0 199 5 0.0 1966.0 573.1 2183.0 141.6 0.0 0.0 0.0 0.0 0.0 0.0 0.0 199 1470. 6 94.5 3 2023.5 2741.9 688.0 65.3 62.8 0.0 0.0 0.0 0.0 0.0 199 130. 887. 7 371.9 1533.5 4028.8 1304.4 241.9 0 9 0.0 0.0 0.0 0.0 0.0 199 358. 8 0.0 967.3 3148.1 6889.9 1669.8 8 36.5 0.0 0.0 0.0 0.0 0.0 199 9 349.8 1523.4 2260.6 274.9 47.7 0.0 0.0 0.0 0.0 0.0 0.0 0.0 200 0 881.3 115.7 3299.8 2039.1 402.5 0.0 0.0 0.0 0.0 0.0 0.0 0.0 200 1 137.8 3150.6 1828.6 2348.4 1047.6 0.0 0.0 0.0 0.0 0.0 0.0 0.0 200 2 481.2 2891.7 4349.0 9783.7 428.1 53.2 0.0 0.0 0.0 0.0 0.0 0.0 200 3 0.0 1966.0 573.1 2183.0 141.6 0.0 0.0 0.0 0.0 0.0 0.0 0.0 200 4 94.5 1470.3 2023.5 2741.9 688.0 65.3 62.8 0.0 0.0 0.0 0.0 0.0 200 130. 887. 5 371.9 1533.5 4028.8 1304.4 241.9 0 9 0.0 0.0 0.0 0.0 0.0 200 358. 6 0.0 967.3 3148.1 6889.9 1669.8 8 36.5 0.0 0.0 0.0 0.0 0.0

284 5.17.3 Priorities / Operation Policy

The Reservoir Simulation studies were carried out considering the above monthly net inflows into the reservoirs and monthly demands to be met from the reservoirs in the following order of priorities.

5.17.4 Demands 5.17.4.1 Common Demands at Each Reservoir (i) Evaporation Losses

At each reservoir, evaporation losses (a natural hydrological process) will have to be first met irrespective of the status of storage. The annual pan evaporation data for the Pinjal reservoir is available in the ‘Yield Study report of Gargai and Pinjal rivers’ has been applied for Jheri, Paikhed, Chasmandva, Chasmandva barrage, Dabdar and Kelwan dams. The pan evaporation data for the Madhuban (Damanganga) reservoir is available in the Damanganga project working tables which has been applied for Paikhed barrage, Chikkar dam and Ukai reservoirs also. ii) Environmental Demand

In order of priority, the next demand considered at each reservoir is release of minimum flows downstream during the lean season.

The minimum environmental flow demand in the river is considered as 10% of the average annual lean season flows at the respective reservoirs/Weirs during the period from October to May are given in Table 5.60:

Table 5.60 Demands for Environmental flow Sl. Reservoir / Weir Minimum Downstream Release for No. Environmental Needs (MCM) 1 Jheri reservoir 4.40 2 Paikhed reservoir 3.20 3 Paikhed barrage 0.00 4 Chasmandva reservoir 0.80 5 Chasmandva barrage 0.00 6 Chikkar reservoir 1.60 7 Dabdar reservoir 4.00 285 Sl. Reservoir / Weir Minimum Downstream Release for No. Environmental Needs (MCM) 8 Kelwan reservoir 4.80 9 Ukai reservoir 0.00 Total 18.80

The d/s releases for environmental purpose from each reservoir are proposed to be met from each reservoir until it reaches its Dead storage level (i.e., keeping the monthly live storage as zero).

5.17.4.2 Project Specific Demands

After meeting the above common demands, the project specific demands at each of the reservoirs are considered in certain order of priority as detailed below under each reservoir. As the rivers are non-perennial in nature, there would not be any inflow into the reservoir during the non monsoon period. Each reservoir has to meet its mandatory evaporation losses and environmental demand without fail, therefore month-wise minimum live storages (cut-off storages) are proposed to be maintained in respect of each project specific demand from the reservoir, in accordance with their order of priority.

The various Water demands that are proposed to be met from proposed reservoir are considered in the following order.

382 MCM for en-route irrigation , 285 MCM for the Projects proposed by the Government of Gujarat on the left side of canal, 138 MCM for Tribal area enroute right side of canal, 48 MCMfor Tribal area in the vicinity of reservoirs, 90 MCMand 40 MCMfor Tribal areas on right side of Narmada main canal by lift in Chhota Udepur dist and Panchmahal dist. respectively,48 MCM towardsSupply of drinking water for all villages of Dang District and Villages of Kaprada and Dharmpur taluka of Valsad District, 18 MCMfor filling all possible tanks in benefitted areas, and 161 MCMfor Target command in Saurashtra region

The Water Demands

(i) Domestic & Industrial Use and Filling of tanks in the Periphery of Reservoirs

286 (ii) Supply of Drinking water for villages and filling of village and Panchayat tanks

A provision of 76 MCM has been made for supply of drinking water to 27.5 lakh populations for villages of Valsad, Navsari, Dang, Tapi, Surat, Bharuch, Narmada and Vadodara district of Gujarat and Nasik district in Maharashtra State.

In adition to above, provision of 50 MCM has been kept for filling of 2226 village and panchayat tanks located in Valsad, Navsari, Dang, Tapi, Surat, Bharuch, Narmada and Vadodara district of Gujarat and Nasik district in Maharashtra State.

(i) Drinking water supply (GWSSB) for all villages of Dangs District, villages of Kaprada and Dharampur talukas of Valsad District and filling of tanks in the Command Area (66 MCM)

Drinking water supply (GWSSB)for all villages of Dangs District, villages of Kaprada and Dharampur talukas of Valsad Districtand filling of tanks in the Command Area,a provision of 66 MCMis made under the link project.

(ii) Irrigation Demand of Feeder pipelinefrom the Project ( 7.9 MCM)

The irrigation demand of Dabdar Feeder pipeline at 3.9 MCMto be met from Dabdar reservoir and irrigation demand of Kelwan Feeder pipeline at 4.0 MCMto be met from Kelwan reservoir are considered.

(iii) Irrigation demand in the periphery of six reservoirs (48 MCM)

The irrigation demand in the periphery of six reservoirs is furnished in Table 5.61: Table 5.61 Irrigation demand in the periphery of six reservoirs Sl. No. Reservoir / Weir Irrigation demand (MCM) 1 Jheri reservoir 3.7 2 Paikhed reservoir 14.5 3 Chasmandva reservoir 9.0 4 Chikkar reservoir 4.8 5 Dabdar reservoir 10.0 6 Kelwan reservoir 6.1 287 Total 48.0

(iv) Water Demand for en-route irrigation under the Link Canal

The water demand for en-route irrigation under the link canal is 1096 MCM which include the requirements of: i) En-route command area including command area of Feeder pipelines– 382 MCM, ii) Command Area of five proposed projects of Government of Gujarat – 285 MCM, iii) Command Area proposed right side of Link Canal and Narmada Main Canal (by substitution) by lift – 268 MCM and iv) Target Command Area (by substitution) – 161 MCM.

The waters from the reservoirs are released as per the demand pattern of the command area along the link canal. The reach wise monthly demands of the link canal are given in Table 5.62:

Table 5.62 Reach wise Monthly Demand of the Link Canal Unit: MCM . l l l a a h d d d o a a a t g g t t t n n n n N n o n o o o a a

o . a a a a y T T T l r r e c n d d d S i M u u r

B n n n

b i u A A a a a

a m P d d i k m m m n A e e e n p U a a a a D D D

a n T c d d d r i e n n u b h o o P y y k m i e e A a B B P a a c n i r b u m P A (1) (2) (3) (4) (5) (6) (7) (8) (9) 1 Jun 75.6 14.8 2.9 57.9 2.4 55.5 13.0 42.5 2 Jul 55.3 11.5 2.1 41.7 1.7 40.0 9.8 30.2 3 Aug 56.8 10.4 1.8 44.6 1.6 43.0 9.6 33.4 4 Sept 103.6 11.2 1.9 90.5 1.9 88.6 15.5 73.1 5 Oct 128.0 27.2 3.6 97.2 1.9 95.3 25.8 69.5 6 Nov 167.6 22.5 5.5 139.6 5.2 134.4 24.8 109.6 7 Dec 131.1 22.4 4.7 104.0 4.0 100.0 21.5 78.5 8 Jan 144.8 23.6 4.8 116.4 4.0 112.4 23.7 88.7 9 Feb 125.0 17.6 4.3 103.1 4.1 99.0 18.5 80.5 288 10 Mar 82.3 11.6 3.1 67.6 3.1 64.5 11.5 53.0 11 Apr 45.6 11.5 1.8 32.3 1.2 31.1 9.0 22.1 12 May 39.1 9.6 1.5 28.0 1.1 26.9 7.6 19.3 Total 1154.8 193.9 38.0 922.9 32.2 890.7 190.3 700.4 Say 1154 194 38 922 32 890 190 700

The monthly minimum live storages are assumed for different dependabilities to be met at required successes rates (cut off storages) to be maintained at each of the reservoir/barrage

5.17.5 Multi Reservoir Simulation Study

Simulation studies have been carried out considering the Area – Elevation - Capacity tables of respective reservoirs, net inflows, evaporation depths, irrigation demands for irrigation, domestic, industrial and downstream releases for environmental purposes.

5.17.5.1 Reservoir Operation Policy / Priorities

The priorities considered for release of water for various purposes from the reservoirs is as under.

 Evaporation losses in the reservoir/barrages.  Releases for environmental purposes to be met at 90 to 100% success rate.  Domestic and industrial requirements to be met at 93 to 100% success rate.  Irrigation demands at the reservoir to be met at a minimum of 75% success rate.  Downstream releases to meet irrigation demands at a minimum of 75% success rate  Demands of the link canal to be met at a minimum of 75% success rate

The demands are proposed to be met from the spills of the reservoirs and balance demand is proposed from the storages on the priority mentioned above.

289 (i) Irrigation Demand below Chasmandva Barrage: The deficit in irrigation demand below Chasmandva barrage is proposed to be met on priority from Paikhed reservoir and Jheri reservoir.

(ii) Link Canal Demand between Ambica and Purna River: The demand of 32 MCM is proposed to be met from Dabdar reservoir. The deficit of the link canal demand is proposed to be met from Chikkar reservoir, Chasmandva reservoir, Paikhed reservoir and Jheri reservoir on priority.

(iii) Link Canal Demand between Purna and Tapi River: The demand of 190 MCM is proposed to be met from Kelwan reservoir. The deficit of the link canal demand is proposed to be met from Dabdar reservoir, Chikkar reservoir, Chasmandva reservoir, Paikhed reservoir and Jheri reservoir on priority.

(iv) Link Canal Demand beyond Tapi River: The demand of 700 MCM is proposed to be met from Kelwan reservoir. The deficit of the link canal demand is proposed to be met from Dabdar reservoir, Chikkar reservoir, Chasmandva reservoir, Paikhed reservoir and Jheri reservoir on priority.

5.17.5.2 Assumptions in the Simulation Study

(1) Computation of Reservoir Evaporation Losses Reservoir evaporation MCM = Submergence area at beginning of the Month * pan evaporation in mm / day * number of days in the month / 100000

(2) Setting of Initial Storage of the Reservoir The initial storage of the reservoir are assumed as 10% of the live Storage plus dead storage of the reservoir.

(3) The Minimum Storages Proposed in each Reservoir The minimum storages are proposed for meeting the demand for evaporation losses, environmental demands and domestic demand for meeting the required success rate.

290 (4) If the annual deficit falls less than 10% of demand is considered as success year

(5) Designed Demand through Canals in various Reaches (MCM)

1 Demand between Paikhed and Auranga 194.00 Demand between Auranga and Ambica river 38.00 2 Demand between Ambica and Purna river 32.00 3 Demand between Purna and Tapi river 190.00 4 Demand Beyond Tapi river 700.00

Total 1154.00 The above demand is inclusive of transmission losses at 12% of diversion.

5.17.6 Simulation Results and Observations:

Using the above inputs, the multi reservoir simulation studies were carried out for the period from 1975-2006 i.e., 32 years. The diversion quantities and other demands of the link are optimized with storages proposed in the reservoirs. The results are described below.

(i) Evaporation losses of the reservoir: The annual evaporation losses worked out for different reservoirs and required quantity of water has been kept for maintaining the storage of each reservoirs and are given in Simulation studies.

(ii) Environmental and Ecological Needs: About 10% of the 75% dependable lean season flow is considered for this purpose. It is seen from simulation studies that this demand is being met at 90 to 100% success rate in all the reservoirs

(iii) Irrigation Demands under the Reservoirs: a) The local irrigation demands at Kelwan dam and Dabdar dam are 4.0 and3.9 MCM respectively. These demands are met at 96% success rate.

b) The total irrigation demand at the periphery of six reservoirs is 48 MCM. The success rate in meeting the demand at Jheri, Paikhed,Chasmandava and Chikkar dams is 100%, where as the

291 same at Dabdar and Kelwan reservoirs is 96% and 93% respectively.

(iv) Domestic Requirement for filling Tanks/Check dams : The local domestic demands is considered as 60 MCM from the proposed Jheri, Paikhed, Chasmandva, Chikkar, Dabdar and Kelwan reservoirs @ 10.0 MCM each of the reservoir. These demands are met at 93 to 100% success rate.

(v) Link Canal Demands for Diversion of Water: (1) The annual link canal demand of 38MCM between Auranga and Ambica rivers met at 93% success rate. The Maximum deficit for the demand in this reach is up to 2 MCM. (2) The annual link canal demand of 32 MCMbetween Ambica and Purna river is met at 100% success rate. (3) The annual link canal demand of 190 MCM between Purna and Tapi river is met at 96% success rate. (4) The annual link canal demand of 700 MCM beyond Tapi river is met at 84.0 % success rate. (5) The annual link canal demands of 194 MCM between Paikhed and Chasmandava feeder pipeline is met at 93% success rate.

(vi) Canal and Tunnel Capacity:The designed discharge capacity of canals and tunnels betweenvarious reaches for the Par-Tapi-Narmada link are given in Table 5.63.

Table 5.63 Designed Diversion Capacity of Canals and Tunnels

Reservoir / Canal/Tunnel Capacity Weir/Canal (cumec) Jheri Reservoir Tunnel connecting Jheri and Paikhed reservoirs 12.80 Paikhed Weir Par-Tapi-Narmada Link Canal at head 38.17 Link Canal Link Canal between Paikhed weir and 38.17 Chasmandva Feeder(RD 0.00 to 62.072 km) Chasmandva Weir Chasmandva Feeder Pipeline 8.50 Link Canal Link Canal between Chasmandva Feeder and 46.64 Dabdar Feeder(RD 62.072 to 108.250 km) Chikkar Reservoir Chikkar and Dabdar inter-connecting canal 6.40 Dabdar Reservoir Dabdar Feeder Pipeline 17.00 Link Canal Link Canal between Dabdar Feeder and 46.64 292 Kelwan Feeder(RD 108.250 to 129.600 km) Kelwan Reservoir Kelwan Feeder Pipeline 17.00 Link Canal Link Canal between Kelwan Feeder and Ukai 63.69 reservoir(RD 129.600 to 177.736 km) Link Canal Off-take from Ukai reservoir(Tapi – Narmada 46.64 canal at Head) RD 51.043 to 69.150 Km 36.40 RD 69.150 to 82.171 Km 31.89 RD 82.171 to 191.307Km 17.26

Conclusion

The simulation studies are carried out based on the data available and assumptions. Based on the data and assumptions the various demands are met successfully for all 12 months. However, the transfer of water is restricted to around 11 months only, instead of transferring the water throughout the year for maintaining the canal and optimum utilization of overall system. Out of total 1330 MCM of water to be transferred; about 108 MCM of water will be utilized in the vicinity of the six proposed reservoirs for various purposes as mentioned above, after allocation of 20 MCM towards downstream releases from the above reservoirs to meet environmental needs and 40 MCM towards evaporation losses from these reservoirs, annually. Thus, a total net quantum of 1210 MCM of water is planned to divert from these reservoirs/ barrages to the Par-Tapi-Narmada link canal at 75% success rate.

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