Drainage Master Plan for NCT of Delhi Final Report July 2018 Prepared for: Department of Irrigation & Flood Control Government of Delhi DEPARTMENT OF CIVIL ENGINEERING Indian Institute of Technology Delhi Hauz Khas, New Delhi Contributors to the Study • IIT Delhi Faculty Prof. A. K. Gosain Prof. R. Khosa Prof. B. R. Chahar Prof. D. R. Kaushal Dr. C. T. Dhanya • IIT Delhi Research Scholars Mr. Satish Kumar Ms. Anupriya Goyal Ms. Harsha Yadav and others • INRM Staff Dr. Sandhya Rao Ms. Puja Singh Ms. Anamika Arora • GSDL Staff • People from various departments of Delhi I&FC, IMD, PWD, DDA, All Municipalities, Cantonment Board, DJB, DSIIDC, DIAL, etc. Table of Contents TABLE OF CONTENTS ........................................................................................................................................................ I LIST OF FIGURES .............................................................................................................................................................. V LIST OF TABLES ............................................................................................................................................................. VIII ABBREVIATIONS .............................................................................................................................. X EXECUTIVE SUMMARY .................................................................................................................. XII 1. INTRODUCTION ....................................................................................................................... 1 1.1 SCOPE OF THE STUDY .............................................................................................................. 1 1.2 DRAINAGE SYSTEM IN THE NCT REGION ................................................................................. 1 1.3 INSTITUTIONAL JURISDICTIONS .............................................................................................. 5 1.4 THE SCALE OF INSTITUTIONAL MONITORING OF FLOOD EVENTS ........................................... 6 1.5 INITIATIVES BY IIT DELHI AND SOME OBSERVATIONS FROM FIELD VISITS .............................. 6 2. DRAINAGE MASTER PLAN METHODOLOGY ............................................................................ 8 2.1 METHODOLOGY OVERVIEW .................................................................................................... 8 2.2 MODELS DEPLOYED ............................................................................................................... 10 2.2.1 SWAT – HYDROLOGICAL MODEL ..................................................................................................................... 10 2.2.2 SWMM/PCSWMM – URBAN STORM WATER MANAGEMENT MODEL ..................................................... 10 2.3 DATA USED ............................................................................................................................ 11 2.4 HANDLING OF STORM DRAIN DATA ...................................................................................... 13 2.5. DATA LIMITATIONS AND ASSUMPTIONS ............................................................................... 15 2.6. SIMULATION SCENARIOS GENERATED .................................................................................. 19 2.6.1. SIMULATION WITH THE DATA PROVIDED BY THE DEPARTMENTS ...................................................................... 19 2.6.2. SIMULATION WITH CHANGED/CORRECTED CROSS SECTIONS OF THE DRAINS .................................................. 19 2.6.3. SIMULATION AFTER INCORPORATING THE EXISTING WATER BODIES ................................................................ 20 2.6.4. SIMULATION AFTER DIVERTING STORM WATER TO ADDITIONAL STORAGES/ RECHARGE AREAS ..................... 20 2.6.5. TOWARDS NO FLOODING FOR 2 YEAR RETURN PERIOD STORM ........................................................................ 20 3. BASIN-WISE REPORT ............................................................................................................. 23 3.1. TRANS YAMUNA BASIN ......................................................................................................... 23 3.1.1. INTRODUCTION ................................................................................................................................................... 23 3.1.1.1. Basin characteristics .......................................................................................................... 23 3.1.1.2. Population statistics .......................................................................................................... 24 3.1.1.3. Topography and land use .................................................................................................. 26 3.1.1.4. Rainfall and groundwater scenario ................................................................................... 28 3.1.2. DETAILS OF EXISTING DRAINAGE NETWORK AS CAPTURED ............................................................................... 30 3.1.3. MAJOR DRAINAGE PROBLEMS IN THE REGION .................................................................................................. 31 3.1.4. SIMULATION SCENARIOS .................................................................................................................................... 34 i DELHI DRAINAGE MASTER PLAN | IIT Delhi F I N A L R E P O R T 3.1.4.1. Scenario 1 – Simulation with data provided by the departments .................................... 34 3.1.4.2. Scenario 2 – Simulation with changes made to cross-sections ........................................ 34 3.1.4.3. Scenario 3 – Simulation towards rejuvenation of water bodies ....................................... 39 3.1.4.4. Scenario 4– Simulation with public parks as recharge zones ........................................... 43 3.1.4.5. Scenario 5 - Towards no flooding junction for 2 year return period storm ...................... 47 3.1.4.6. Comparison of Simulations with 2 year and 5 year return period rainfall events ............ 55 3.2. BARAPULLAH BASIN............................................................................................................................................ 58 3.2.1. INTRODUCTION ................................................................................................................................................... 58 3.2.1.1. Basin characteristics .......................................................................................................... 58 3.2.1.2. Population statistics .......................................................................................................... 59 3.2.1.3. Topography and land use .................................................................................................. 60 3.2.2. DETAILS OF EXISTING DRAINAGE NETWORK ....................................................................................................... 62 3.2.3. MAJOR DRAINAGE PROBLEMS IN THE REGION .................................................................................................. 63 3.2.4. DATA LIMITATIONS AND ASSUMPTIONS ............................................................................................................ 65 3.2.5. SIMULATION SCENARIOS .................................................................................................................................... 69 3.2.5.1. Scenario 1 – Simulation with data provided by the departments .................................... 69 3.2.5.2. Scenario 2 – Simulation with changes made to cross-sections ........................................ 70 3.2.5.3. Scenario 3 – Simulation towards rejuvenation of water bodies ....................................... 73 3.2.5.4. Scenario 4 – Simulation with public parks as recharge zones........................................... 76 3.2.5.5. Scenario 5 - Towards no flooding junction for 2 year return period ................................ 80 3.2.5.6. Comparison of Simulations with 2 year and 5 year return period rainfall events ............ 85 3.3. NAJAFGARH BASIN ............................................................................................................................................. 87 3.3.1. INTRODUCTION ................................................................................................................................................... 87 3.3.1.1. Basin characteristics .......................................................................................................... 87 3.3.1.2. Population statistics .......................................................................................................... 88 3.3.1.3. Topography and land use .................................................................................................. 89 3.3.2. DETAILS OF EXISTING DRAINAGE NETWORK ....................................................................................................... 91 3.3.3. MAJOR DRAINAGE PROBLEMS IN THE REGION .................................................................................................. 92 3.3.4. SIMULATION SCENARIOS .................................................................................................................................... 95 3.3.4.1. Scenario 1 – with data provided by the departments ...................................................... 95 3.3.4.2. Scenario 2 – with changes made to cross-sections ..........................................................