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Xj a I%ARTIL i! f 4-4 .=44 !ffiS96-- * +<6 @ -*s ¢ r J t X I.S _ Public Disclosure Authorized $ 4~~~~4 S 444.44. -; K.ON- Public Disclosure Authorized .4 C'~~~~~~- 4 .,< drS nvftat' S -. 4• -"4--pt ~~~~~~~~~~~~>44z AP -r 4 ~~~~~~~~~~~~~~- -4t L~~*esPakt(tn) Lt . < - : -~ .4: . - :d'44fes-r-m t.4 Public Disclosure Authorized &~~~~~~~~~~~~~~~-Bmi & ater OIsos t TABLE OF CONTENTS c GRAZI-BAROTHA HYDROPOWER PROJECT REPORT ON SUPPLEMENTARY ENVIRONMENTAL STUDIES TABLE OF CONTENTS Page CHAPTER 1 INTRODUCTION 1.1 GENERAL 1.1 1.2 GENERAL DESCRIPTION OF THE PROJECT 1.1 1.3 PREVIOUS ENVIRONMENTAL STUDIES 1.2 1.4 CONCLUSIONS AND RECOMMENDATIONS OF THE ENVIRONMENTAL REVIEW PANEL 1.2 1.5 SUPPLEMENTARY ENVIRONMENTAL STUDIES 1.3 1.6 APPENDICES 1.4 REFERENCES CHAPTER 2 ECOLOGICAL ASPECTS OF THE INDUS RIVER FLOOD PLAIN 2.1 INTRODUCTION 2.1 2.2 APPROACH 2.1 2.3 MORPHOLOGICAL AND ECOLOGICAL SETTING OF THE RIVERAIN AREA 2.2 2.4 PLANT COMMUNITIES IN VARIOUS HABITATS 2.3 2.4.1 General 2.3 2.4.2 Braided Alluvial Channel 2.3 2.4.3 Attock Gorge 2.5 2.4.4 Alluvial Basin 2.6 2.5 WILDLIFE USE OF HABITATS 2.6 2.5.1 Open Water 2.6 2.5.2 Temporary Belas 2.6 2.5.3 Permanent Belas 2.7 2.5.4 Ind-ds Gorge 2.8 2.6 POTENTIAL EFFECTS OF THE PROJECT 2.8 2.6.1 Effects on Natural Vegetation 2.8 2.6.2 Effects on Wildlife 2.10 (i) Page 2.7 CONCLUSION 2.11 REFERENCES CHAPTER 3 WASTEWATER DISPOSAL AND WATER QUALITY 3.1 INTRODUCTION 3.1 3.1.1 Background 3.1 3.1.2 Scope 3.1 3.2 WASTEWATER FLOWS 3.2 3.2.1 Existing Situation 3.2 3.2.2 Future Situation 3.3 3.3 WASTEWATER QUALITY 3.5 3.3.1 Sampling and Testing 3.5 3.3.2 Comments on the Results 3.6 3.4 RIVER WATER ASSIMILATIVE CAPACITY BY MASS BALANCE (DILUTION) METHOD 3.6 3.5 CONCLUSIONS 3.8 REFERENCES TABLES CHAPTER 4 PUBLIC AND ANIMAL HEALTH 4.1 INTRODUCTION 4.1 4.2 APPROACH TO STUDY 4.1 4.2.1 General 4.1 4.2.2 Literature Search Vector-borne Diseases in Pakistan 4.2 4.2.3 Interviews with Pakistani Health Workers 4.2 4.2.4 Field Survey 4.2 4.3 GENERAL HEALTH CONDITION IN PAKISTAN 4.3 4.4 HEALTH RISKS ASSOCIATED WITH THE PROJECT 4.3 4.4.1 Malaria 4.3 4.4.2 Other Vector-borne Diseases 4.7 4.4.3 Blackfly (Simuliuma 4.10 4.5 TYPICAL BREEDING SITES OF ANOPHELES AND SIMULIUM IN THE INDUS RIVER AND ASSOCIATED NULLAHS 4.10 (ii) Page 4.6 CONCLUSIONS 4.11 4.6.1 General 4.11 4.6.2 Project Zones of Health Influence 4.11 4.6.3 Changes in Aquatic Environment 4.12 4.6.4 Malaria 4.12 4.6.5 Leishmaniasis 4.12 4.6.6 Bilharzia 4.12 4.6.7 Guinea Worm 4.13 REFERENCES CHAPTER 5 ARCHAEOLOGICAL AND AESTHETICAL ASPECTS 5.1 RESUME OF THE PREVIOUS ARCHAEOLOGICAL STUDIES 5.1 5.2 FURTHER STUDIES 5.1 5.2.1 Archaeological Studies of Borrow Areas 5.1 5.2.2 Aesthetic Aspects of the Attock Gorge 5.2 5.3 FINDINGS OF STUDY 5.2 5.3.1 Archaeological Studies of Borrow Areas 5.2 5.3.2 Aesthetic Aspects of the Attack Gorge 5.3 5.4 CONCLUSIONS 5.4 REFERENCES DRAWINGS APPENDIX A LIST OF PREPARERS AND CONTRIBUTORS APPENDIX B LIST OF CONTACTS APPENDIX C OTHER LITERATIJRE STUDIED APPENDIX D SPECIES OF FLORA ENCOUNTERED (iii) APPENDIX E SPECIES OF FAUNA ENCOUNTERED APPENDIX F DESCRIPTION OF ANOPHELES AND SIMULIUM BREEDING SITES INVESTIGATED (iv) REPORT ON SUPPLEMENTARY ENVIRONMIENTAL STUDIES LIST OF TABLES No. Title Page 3.1 Population Statistics 3.10 3.2 Population, Wastewater Production, Dilution Requirements and River Water Quality 3.11 3.3 River Water Quality 3.12 3.4 Groundwater Quality 3.13 3.5 Wastewater/Sewage Quality 3.14 (v) REPORT ON SUPPLEMENTARY ENVIRONMENTAL STUDIES LIST OF DRAWINGS No. Title 1.1 General Layout of Project Components 2.1 Discharge Rating Curve at Ghazi (L 9) (Average of 1986-1989) 2.2 Climatic Diagram for Tarbela and Attock 3.1 Assumed Wastewater Ingress Points 3.2 Required Dilution Flow 3.3 Dissolved oxygen in Indus (Year 2057) 4.1 Project Area showing Breeding Sites Investigated 4.2 Barrage Pond Fluctuation 4.3 Headpond Fluctuation 4.4 Mosquito Increase Rate (MIR) VS Slide Positive Rate (SPR) 4.5 Rainfall VS Mosquito Increase Rate (MIR) 4.6 Indus River Water Temperature VS Mosquito Increase Rate (MIR) 4.7 Air Temperature VS Mosquito Increase Rate (MIR) 5.1 Location of Borrow Areas (vi) CHAPTER 1 i 5 CHAPTER 1 INTRODUCTION 1.1 GENERAL This Report supplements the Environmental Assessment Report (EAR) that was prepared as part of the feasibility studies for the Project and constituted Volume 7 of the Feasibility Report (Ref. 1.1). The draft EAR was reviewed by an Environmental Review Panel in May 1991. The recommendations of the Panel formed the basis for sfupplementary studies that are presented in this Report. The Project was called the Ghazi-Gariala Hydropower Project until late in 1991, when the name was changed by WAPDA at the request of the people of Barotha. The Project is described in the EAR and, in greater detail, in various other volumes of the Feasibility Rep-ort. For convenience, a brief description of the Project is provided here. 1.2 GENERAL DESCRIPTION OF THE PROJECT The Project will be located in the eastern part of Pakistan's North West Frontier Province and the northern part of the Punjab Province. It consists of three main components: a barrage, a power channel and a power complex (Drawing 1.1). The barrage will be located on the Indus river about 7 km downstream of Tarbela dam, just upstream of the village of Ghazi. It will create a pond with a maximum surface area of 1140 ha at a surface elevation of 340.0 m. During the low-flow season (October to April), when the average daily release from Tarbela is less than the power channel capacity, the barrage pond will provide diurnal re-regulation to ensure a constant flow in the power channel. During this period, the pond level will fluctuate daily by up to 5 m. Water from the barrage pond will be delivered to the power channel through a head regulator. The power channel will have a capacity of 1,600 cumecs (56,500 cusecs) as against the 2,000 cumecs proposed in the Feasibility Report. The capacity has been reduced as a prudent measure in view of the limited experience of channels of this capacity. The power channel will be a concrete-lined, trapezoidal structure approximately 94 m across at the water surface and 9 m deep. It will flow at a velocity of 2.33 m/s and a gradient of 1:9,600 to a forebay which forms the start of the power complex, near Barotha. The power complex will include two headponds, to allow peaking operation while maintaining channel flows uniform, a spillway, an intake structure, 5 penstocks, a powerhouse with 5x290 MW turbine-generators, and a tailrace channel to discharge the water back into the Indus. 1.1 During the high-flow season, when the average daily flow released by Tarbela is greater than the 1,600 cumecs capacity of the power channel, the barrage will release excess flows through undersluices near the left bank and, during high floods, an adjacent set of spillway gates. When Tarbela delivers less water than the capacity of the channel, the barrage will release only compensation water, much of which is expected to result initially from seepage under the barrage. 1.3 PREVIOUS ENVIRONMENTAL STUDIES The environmental assessment of the Project began during the pre-feasibility studies by WAPDA and was continued by the Consultants during the feasibility studies. It is expected that environmental assessments will continue, in one form or another, throughout the life of the Project. Efforts during the pre-feasibility stage focused on the identification of alternatives. During the layout phase of the feasibility studies, attention was focused on the siting and preliminary design of the main components, the locations of the channel crossings, public safety, and the avoidance of impacts on villages, shrines and graveyards. During this stage an excellent working relationship was established between the planning engineers and the environmental staff that resulted in early attention to potential problems. Scoping meetings were held with provincial and district officials, In the subsequent phase of the feasibility study, scoping sessions were held at the Union Council level. Various aspects related to land, water and biological resources, and the socioeconomic conditions of the Project area were studied. These aspects, along with resettlement and other mitigation measures, were discussed in the Draft EAR. 1.4 CONCLUSIONS AND RECOMMENDATIONS OF THE ENVIRONMENTAL REVIEW PANEL The Panel's review found "general acceptability of (a) the approach used in the environmental and social impact analysis of the structural elements of the proposed Project, including siting and design approach for barrage, power channel and power complex; (b) recommended mitigation plan for resettlement and compensation; (c) proposed mitigation plan for archaeological, historical and religious sites." The Panel recommended revisions to the draft environmental assessment to : - strengthen the presentation and analysis of alternatives, environmental impacts, mitigation activities and monitoring plan; and 1.2 include the arrangement for implementing the recommended social mitigation plan and for facilitating economic development in the Project area.