MANAGEMENT OF HILL TORRENTSMANAGEMENT OF HILL TORRENTS

Management of hill torrents crossing the Kachhi Canal Management of hill torrents crossing the Kachhi Canal to reduce the peak flows to safeguard the canal and to to reduce the peak flows to safeguard the canal and to increase the agricultural production in Pachad Areaincrease the agricultural production in Pachad Area

Review alternatives to;Review alternatives to;i.i. Adopt hill torrent management to reduce the peaks or;Adopt hill torrent management to reduce the peaks or;

ii.ii. Remodel existing X-Drainage / Hill Torrent Structures of Remodel existing X-Drainage / Hill Torrent Structures of D.G. Khan Canal and Dajal Branch from RD 0 to RD 531 D.G. Khan Canal and Dajal Branch from RD 0 to RD 531 as per criteria to be adopted for Kachhi Canalas per criteria to be adopted for Kachhi Canal

iii.iii. Review various modern alternatives for hill torrent Review various modern alternatives for hill torrent managementmanagement

D.G.Khan Hill Torrents

MAP OF KAHA HILL TORRENT

GENERAL TYPES OF STRUCTURES FOR GENERAL TYPES OF STRUCTURES FOR MANAGEMENT OF HILL TORRENTMANAGEMENT OF HILL TORRENT

Storage DamsStorage Dams Delay Action DamsDelay Action Dams Check DamsCheck Dams Flood DistributorsFlood Distributors Dispersion StructuresDispersion Structures Diversion DykesDiversion Dykes Cross DykesCross Dykes Flood Irrigation ChannelsFlood Irrigation Channels Flood Disposal ChannelsFlood Disposal Channels

KAHA HILLKAHA HILLTORRENTTORRENT

SCHEMATIC DIAGRAM FOR MANAGEMENT OF FLOWS IN

BALOCHISTAN

SCHEMATIC DIAGRAM FOR MANAGEMENT OF FLOWS IN PACHAD AREA- PUNJAB

Cost of Schemes – RS 130 MillionPotential Area – 36,253 HA

MAP SHOWING MANAGEMENT WORKS ON KAHA HILL TORRENT IN PUNJAB

PROJECT IMPACTPROJECT IMPACTFLOOD PEAK EVENTS/INUNDATIONFLOOD PEAK EVENTS/INUNDATION

YEAR 1973YEAR 1973 FLOOD PEAKFLOOD PEAK 56,000 CFS (1,586 CMS)56,000 CFS (1,586 CMS) BREACHES - DAJAL BRANCHBREACHES - DAJAL BRANCH 148 Nos.148 Nos. DISTYS. DAMAGED DISTYS. DAMAGED - NAUSHERA- NAUSHERA - ZAMZAM- ZAMZAM - ISLAM- ISLAM - ABE-HAYAT- ABE-HAYAT AREA INUNDATEDAREA INUNDATED 45,000 ACRES (18,220 HA)45,000 ACRES (18,220 HA)

PRE-PROJECTPRE-PROJECT

YEAR 2003YEAR 2003FIRST PEAKFIRST PEAK 2ND JULY, 20032ND JULY, 2003 60,000 CFS (1,700 CMS)60,000 CFS (1,700 CMS)SECOND PEAKSECOND PEAK 10TH JULY, 200310TH JULY, 2003 60,000 CFS (1,700 CMS)60,000 CFS (1,700 CMS)THIRD PEAKTHIRD PEAK 14TH JULY, 200314TH JULY, 2003 51,900 CFS (1,470 CMS)51,900 CFS (1,470 CMS)

BREACHESBREACHES 5 No - Relief Cuts5 No - Relief Cuts DISCHARGE AT CANAL CROSSINGSDISCHARGE AT CANAL CROSSINGS 9,000 CFS9,000 CFS AREA INUNDATEDAREA INUNDATED NOMINALNOMINAL

POST-PROJECTPOST-PROJECT

PRE & POST-PROJECT ATTENUATION OF FLOOD PEAKSPRE & POST-PROJECT ATTENUATION OF FLOOD PEAKSFOR KAHA HILL TORRENTFOR KAHA HILL TORRENT

PEAK AT DARRAH FLOOD PEAK AT HILL TORRENT CROSSINGS

PRE-PROJECT POST-PROJECT

40,000 15,000 0

50,000 23,000 2,500

60,000 31,000 4,500

70,000 39,000 9,000

80,000 48,000 14,000

Discharge - CFS

CROPPING PATTERN AND INTENSITIES CROPPING PATTERN AND INTENSITIES UNDER PRE AND POST PROJECT CONDITIONSUNDER PRE AND POST PROJECT CONDITIONS

Crops Pre Project Post Project

  Cropped Area (HA) Intensity (%) Cropped Area (HA) Intensity (%)

Kharif        

Sorghum 1,817 5.0 8,983 24.8

Bajra 277 0.8 1,864 5.1

Cotton 0 0.0 1,831 5.1

K.Total 2,094 5.8 12,678 35.0

Rabi        

Wheat 465 1.3 1,926 5.3

Gram 141 0.4 591 1.6

Oilseed 199 0.5 6,597 18.2

R.Total 805 2.2 9,114 25.1

Annual 2,899 8.0 21,792 60.1

CCA = 36,253 HA

PROPOSED AND ACTUALLY BENEFITED AREAS AGAINST PROPOSED AND ACTUALLY BENEFITED AREAS AGAINST VARIOUS PEAK FLOODSVARIOUS PEAK FLOODS

Crops

Proposed at Feasibility Level Achievement under Post Project Period

Return Periods - Years Return Periods - Years

2.33 5 10 25 2.33 5 10 25

Jawar 9,769 18,788 23,349 23,595 7,214 13,874 17,242 17,424

Bajra 1,489 2,863 3,559 3,597 1,100 2,114 2,628 2,656

Wheat 1,760 3,386 4,209 4,699 1,300 2,501 3,108 3,470

Gram 534 1,028 1,275 1,425 394 759 942 1,053

Oilseed 753 1,446 1,800 2,011 556 1,068 1,329 1,485

Total: 14,306 27,512 34,192 35,328 10,564 20,316 25,250 26,088

CCA = 36,253 HA

COMPARISON OF ECONOMIC INDICATORSCOMPARISON OF ECONOMIC INDICATORS

Sr. No.

Item UnitPre-Project in

Feasibility Report 1990

Post-Project in Evaluation Report

2003

1 Financial Project Cost Rs. Million 190.26 364.9

  - Balochistan Works Rs. Million 60 -

  - Punjab Works Rs. Million 130.26 364.9

2 Economic Project Cost Rs. Million 171.23 329.91

3 Implementation Period Years 3 5

4 Project Annual Benefits Rs. Million 33.8 84.03

  - Agriculture Benefit Rs. Million 14.72 25.5

  - Flood Damage Saving Rs. Million 19.08 58.53

5 Economic Parameters      

  - Economic Interval Rate of Return Percent 17.38 19.99

  - Benefit Cost Ratio at 10% Discount Ratio 1.63:1 1.91:1

  - Net Present Worth at 10% Discount Rs. Million 108.3 263.21

FUTURE STRUCTURAL IMPROVEMENTSFUTURE STRUCTURAL IMPROVEMENTS

A.A. PROP WALL CONSTRUCTED UNDER THE CREST ON D/S SHOULD BE PROP WALL CONSTRUCTED UNDER THE CREST ON D/S SHOULD BE PLACED UPSTREAM UPTO CREST LEVEL TO ENSUREPLACED UPSTREAM UPTO CREST LEVEL TO ENSURE

Uniform flowUniform flow Check washing of finesCheck washing of fines Safety Against ScourSafety Against Scour

B.B. ORDER OF CONSTRUCTIONORDER OF CONSTRUCTION Construction must start from Darrah to down streamConstruction must start from Darrah to down stream

C.C. DEGREE OF PROTECTIONDEGREE OF PROTECTION Down stream works need more protection as compared to the Down stream works need more protection as compared to the

upper onesupper ones

D.D. STRCTURAL IMPROVEMENTSSTRCTURAL IMPROVEMENTS Upper end of Salai should be semi circular instead of rectangularUpper end of Salai should be semi circular instead of rectangular Terminal end should be similar to that of guide bundTerminal end should be similar to that of guide bund Off-take should be located >10 H above the cross structureOff-take should be located >10 H above the cross structure For H < 2 meter falls with glacis be adopted instead of drop fallsFor H < 2 meter falls with glacis be adopted instead of drop falls

COST OF STRUCTURAL INTERVENTIONSCOST OF STRUCTURAL INTERVENTIONS PUNJAB PROVINCEPUNJAB PROVINCE RS.MILLION

SCENARIO - 1. WITHOUT DISPERSION STRUCTURES

• Cost of 40 Cross-Drainage Structures on Kachhi Canal RD: 0 – 990 (Punjab) 2,184

• Cost for increasing Flood Carrying Capacity Against 40-Year Return Period on D.G.Khan Canal System: (a) Excluding cost of flood carrying channels (b) Including cost of flood carrying channels

813

1,194

Sub Total (a) Sub Total (b)

2,997

3,378

SCENARIO - 2. WITH DISPERSION STRUCTURES

• Dispersion Works in Pachad Area and Flood Carrying ChannelsRD: 0 – 990

1,363

• Constructing Drainage works on Kachhi Canal Corresponding to ExistingX-Drainage Structures on D.G.Khan Canal System

TotalBALOCHISTAN PROVINCECost of flood management for Nallahs Orignating from Marri Bughti Hills &Mountainous Regions upto Gandava/Badra Nallah

1,920

3,283

750

FINDINGS & CONCLUSIONSFINDINGS & CONCLUSIONS

Efficacy of existing cross-drainage structures on DG Khan & Dajal branch Efficacy of existing cross-drainage structures on DG Khan & Dajal branch be evaluated.be evaluated.

Flood peak attenuation at cross-drainage structures through dispersion Flood peak attenuation at cross-drainage structures through dispersion structures is significant.structures is significant.

Suggested improvement in the design of structural interventions be taken Suggested improvement in the design of structural interventions be taken into account in future hill torrent projects.into account in future hill torrent projects.

In spite of shortcoming in design, diversion of flood flows in Pachad area In spite of shortcoming in design, diversion of flood flows in Pachad area has been reasonable during post-project environments.has been reasonable during post-project environments.

Construction of dispersion structures in Pachad area is technically and Construction of dispersion structures in Pachad area is technically and socially more attractive than disposal of flows into Indus River.socially more attractive than disposal of flows into Indus River.

Ensure the availability of funds for O&M at proper time.Ensure the availability of funds for O&M at proper time.

Existing & future users of canal water on the right bank through lift pumps Existing & future users of canal water on the right bank through lift pumps be duly considered for planning & design of Kachhi Canal.be duly considered for planning & design of Kachhi Canal.

RECOMMENDATIONSRECOMMENDATIONS Dispersion Structures in Pachad Area on Sori- Dispersion Structures in Pachad Area on Sori-

Lund, Sakhi Sarwar,Vidore, Chachar, Zangi & Lund, Sakhi Sarwar,Vidore, Chachar, Zangi & Shori Janubi and Flood Carrying Channels in Shori Janubi and Flood Carrying Channels in Command Area be constructed.Command Area be constructed.

Carrying Channels leading to Indus River for Carrying Channels leading to Indus River for Pitock and Shori Shumali be constructed.Pitock and Shori Shumali be constructed.

Cross drainage Structures on Kachhi Canal be Cross drainage Structures on Kachhi Canal be constructed as per D G Khan & Dajal Canal constructed as per D G Khan & Dajal Canal System.System.

Dispersion Structures would facilitate in the Dispersion Structures would facilitate in the irrigation of additional area of about 80,000 HA.irrigation of additional area of about 80,000 HA.

Provision may be made for Channelization of Provision may be made for Channelization of water along the right-bank through water along the right-bank through embankments constructed water course embankments constructed water course crossing Pipelines.crossing Pipelines.

STUDIES PLANNED TO BE STUDIES PLANNED TO BE CARRIED OUT BY CONSULTANTSCARRIED OUT BY CONSULTANTS

Frequency analysis of flood flows of nallahs/rivers at darrah(s) and at Frequency analysis of flood flows of nallahs/rivers at darrah(s) and at canal drainage structures.canal drainage structures.

Study the adequacy of existing cross draining structures on DG khan Study the adequacy of existing cross draining structures on DG khan system in the light of frequency analysis.system in the light of frequency analysis.

Remodeling of existing cross drainage structures if inadequate and Remodeling of existing cross drainage structures if inadequate and additional structures if required on DG Khan canal / Dajal Branch.additional structures if required on DG Khan canal / Dajal Branch.

Consultants should advise for alternative strategies to irrigate Pachad Consultants should advise for alternative strategies to irrigate Pachad area in lieu of proposed construction of 400 water course crossings on area in lieu of proposed construction of 400 water course crossings on Kachhi CanalKachhi Canal

Consultants will probe that after construction of dispersion structures Consultants will probe that after construction of dispersion structures the flood peak will be reduced in accordance with the existing capacity the flood peak will be reduced in accordance with the existing capacity of cross drainage structures on DG Khan system.of cross drainage structures on DG Khan system.

Consultancy proposal for flood management of hill torrents originating Consultancy proposal for flood management of hill torrents originating from Suleiman Range and Marri Bugti hills from Taunsa Barrage to tail from Suleiman Range and Marri Bugti hills from Taunsa Barrage to tail of Kachhi Canal.of Kachhi Canal.

Revision of PC-I to accomodate hill torrent works in Punjab & Revision of PC-I to accomodate hill torrent works in Punjab & Balochistan Provinces.Balochistan Provinces.

THANKSTHANKS