[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"detail-sidebar-cat-0-en-105":3,"doc-seo-649470-105":59,"doc-detail-649470-en":129},{"code":4,"msg":5,"data":6},0,"success",[7,13,18,23,28,33,38,43,48,51,55],{"id":8,"doc_module":4,"doc_module_name":9,"category_name":10,"show_sort_weight":11,"slug":12},1,"Document","Story & Novel",90,"story-novel",{"id":14,"doc_module":4,"doc_module_name":9,"category_name":15,"show_sort_weight":16,"slug":17},2,"Literature",80,"literature",{"id":19,"doc_module":4,"doc_module_name":9,"category_name":20,"show_sort_weight":21,"slug":22},4,"Exam",70,"exam",{"id":24,"doc_module":4,"doc_module_name":9,"category_name":25,"show_sort_weight":26,"slug":27},5,"Comic",60,"comic",{"id":29,"doc_module":4,"doc_module_name":9,"category_name":30,"show_sort_weight":31,"slug":32},6,"Technology",50,"technology",{"id":34,"doc_module":4,"doc_module_name":9,"category_name":35,"show_sort_weight":36,"slug":37},7,"Healthcare",40,"healthcare",{"id":39,"doc_module":4,"doc_module_name":9,"category_name":40,"show_sort_weight":41,"slug":42},8,"Research & Report",30,"research-report",{"id":44,"doc_module":4,"doc_module_name":9,"category_name":45,"show_sort_weight":46,"slug":47},9,"Religion & Spirituality",20,"religion-spirituality",{"id":46,"doc_module":4,"doc_module_name":9,"category_name":49,"show_sort_weight":46,"slug":50},"World Cup","world-cup",{"id":52,"doc_module":4,"doc_module_name":9,"category_name":53,"show_sort_weight":52,"slug":54},10,"Lifestyle","lifestyle",{"id":56,"doc_module":4,"doc_module_name":9,"category_name":57,"show_sort_weight":24,"slug":58},19,"General","general",{"code":4,"msg":60,"data":61},"ok",{"site_id":62,"language":63,"slug":64,"title":65,"keywords":66,"description":67,"schema_data":68,"social_meta":122,"head_meta":124,"extra_data":126,"updated_unix":128},105,"en","part-2-drainage-design-road-design-manual-for-roads-and-bridges","Part 2 - Drainage Design - Road Design Manual for Roads and Bridges","","Road Design Manual for Roads and Bridges Part II: Drainage Design (April 2016, referencing earlier 2009 draft material) sets out drainage design guidance for Kenyan road projects. It establishes basic principles, planning and location considerations, coordination requirements, and physical factors affecting drainage layout. The manual defines design standards using return periods, then provides flood estimation procedures for gauged rivers and non-gauged basins, including rainfall-runoff relationships and practical methods for computing design flows.",{"@graph":69,"@context":121},[70,84,104],{"@type":71,"itemListElement":72},"BreadcrumbList",[73,77,79,82],{"item":74,"name":75,"@type":76,"position":8},"https://docshare.wps.com","Home","ListItem",{"item":78,"name":9,"@type":76,"position":14},"https://docshare.wps.com/document/",{"item":80,"name":40,"@type":76,"position":81},"https://docshare.wps.com/document/research-report/",3,{"item":83,"name":65,"@type":76,"position":19},"https://docshare.wps.com/document/part-2-drainage-design-road-design-manual-for-roads-and-bridges/649470/",{"url":83,"name":65,"@type":85,"image":86,"author":91,"headline":65,"publisher":94,"fileFormat":97,"inLanguage":63,"description":67,"dateModified":98,"datePublished":98,"encodingFormat":97,"isAccessibleForFree":99,"interactionStatistic":100},"DigitalDocument",{"url":87,"@type":88,"width":89,"height":90},"https://docshare.wps.com/thumbnails/part-2-drainage-design-road-design-manual-for-roads-and-bridges/649470.png","ImageObject",300,407,{"name":92,"@type":93},"RuangKosong","Person",{"url":74,"name":95,"@type":96},"DocShare","Organization","application/pdf","2026-10-24",true,{"@type":101,"interactionType":102,"userInteractionCount":14},"InteractionCounter",{"@type":103},"ViewAction",{"@type":105,"mainEntity":106},"FAQPage",[107,113,117],{"name":108,"@type":109,"acceptedAnswer":110},"What topics are covered in Part II of the drainage design manual?","Question",{"text":111,"@type":112},"It covers basic principles, road planning and locating factors affecting drainage, design standards using return periods, and flood estimation for both gauged rivers and non-gauged basins.","Answer",{"name":114,"@type":109,"acceptedAnswer":115},"How does the manual define design standards using return period and design frequency?",{"text":116,"@type":112},"It presents the concept of return period and design frequency, then lists applicable design flow return periods for drainage design.",{"name":118,"@type":109,"acceptedAnswer":119},"What methods are used to estimate flood flow for non-gauged basins?",{"text":120,"@type":112},"It includes the specific discharge method, the rational method (including time of concentration and rainfall intensity), and the TRRL method with parameters such as initial retention, contributing area coefficient, and lag time.","https://schema.org",{"og:url":83,"og:type":123,"og:title":65,"og:site_name":95,"og:description":67},"article",{"robots":125,"canonical":83},"index,follow",{"doc_id":127,"site_id":62},649470,1792843089,{"code":4,"msg":5,"data":130},{"doc_id":127,"user_id":131,"nickname":92,"user_avatar":132,"doc_module":4,"category_id":39,"category_name":40,"doc_title":65,"doc_description":67,"doc_content":133,"file_id":134,"file_url":135,"file_type":136,"file_size":137,"view_count":14,"is_deleted":4,"is_public":8,"is_downloadable":8,"audit_status":8,"page_count":138,"language":139,"language_code":63,"site_id":62,"html_lang":63,"table_of_contents":140,"faqs":141,"seo_title":142,"seo_description":67,"update_tm":143,"read_time":144},962090883219,"https://ap-avatar.wpscdn.com/davatar_276721f389ce27ea32af1340a28f341c","ROAD DESIGN MANUAL FOR ROADS  \nAND BRIDGES  \nPart II: Drainage Design  \nApril 2016  \nDESIGN MANUAL for ROADS and BRIDGES PART 2 – Drainage Design 2009  \nPART 2 –DRAINAGE DESIGN  \nThe Republic of Kenya – Ministry of Roads 1 Draft Document – December 2009  \nDESIGN MANUAL for ROADS and BRIDGES PART 2 – Drainage Design 2009  \nTable of Contents  \nINTRODUCTION ............................................................................................................ 6  \n1 BASIC PRINCIPLES AND CONCEPT ..................................................................7  \n2 PLANNING AND LOCATING OF ROADS AND HIGHWAYS...........................8  \n2.1 INTRODUCTION .................................................................................................... 8  \n2.2 COORDINATION WITH MINISTRIES AND AGENCIES ................................................. 9  \n2.3 LOCATION AND ALIGNMENT CONSIDERATIONS ................................................... 10  \n2.3.1 Horizontal Alignment ................................................................................ 10  \n2.3.2 Vertical Alignment..................................................................................... 11  \n2.4 PHYSICAL CONSIDERATIONS............................................................................... 12  \n2.5 TIDAL AREAS..................................................................................................... 12  \n2.6 LAND USE CONSIDERATIONS .............................................................................. 12  \n2.7 LOCATION OF UTILITIES ..................................................................................... 13  \n2.8 LOCATION OF STORM DRAINAGE FACILITIES ...................................................... 13  \n2.9 TYPE OF STRUCTURE .......................................................................................... 14  \n2.10 CONSTRUCTION-RELATED CONSIDERATIONS ..................................................... 14  \n3 DESIGN STANDARDS AND DESIGN FLOW RETURN PERIODS ................. 16  \n3.1 THE CONCEPT OF RETURN PERIOD AND DESIGN FREQUENCY .............................. 16  \n3.2 APPLICABLE DESIGN FLOW RETURN PERIODS ..................................................... 16  \n4 FLOOD ESTIMATION OF GAUGED RIVERS.................................................. 17  \n4.1 INTRODUCTION .................................................................................................. 17  \n4.2 SOURCES OF RIVER FLOW DATA IN KENYA ......................................................... 17  \n4.3 PROCEDURE ....................................................................................................... 18  \n4.3.1 Data Preparation ...................................................................................... 18  \n4.3.2 Frequency Analysis Concepts .................................................................... 19  \n4.3.3 Plotting Formulas...................................................................................... 19  \n4.3.4 Distribution Function ................................................................................ 20  \n4.3.5 Application Example ................................................................................. 21  \n5 FLOOD ESTIMATION OF NON – GAUGED BASINS ...................................... 23  \n5.1 INTRODUCTION .................................................................................................. 23  \n5.2 SPECIFIC DISCHARGE METHOD ........................................................................... 24  \n5.3 RATIONAL METHOD ........................................................................................... 24  \n5.3.1 Introduction............................................................................................... 24  \n5.3.2 Application ................................................................................................ 24  \n5.3.3 Characteristics ..........................................................","cbCaifaoTOyHbmaO","https://ap.wps.com/l/cbCaifaoTOyHbmaO","pdf",13040091,138,"English","# INTRODUCTION\n# 1 BASIC PRINCIPLES AND CONCEPT\n# 2 PLANNING AND LOCATING OF ROADS AND HIGHWAYS\n## 2.1 INTRODUCTION\n## 2.2 COORDINATION WITH MINISTRIES AND AGENCIES\n## 2.3 LOCATION AND ALIGNMENT CONSIDERATIONS\n## 2.8 LOCATION OF STORM DRAINAGE FACILITIES\n# 3 DESIGN STANDARDS AND DESIGN FLOW RETURN PERIODS\n## 3.1 THE CONCEPT OF RETURN PERIOD AND DESIGN FREQUENCY\n## 3.2 APPLICABLE DESIGN FLOW RETURN PERIODS\n# 4 FLOOD ESTIMATION OF GAUGED RIVERS\n## 4.1 INTRODUCTION\n## 4.3 PROCEDURE\n# 5 FLOOD ESTIMATION OF NON - GAUGED BASINS\n## 5.2 SPECIFIC DISCHARGE METHOD\n## 5.3 RATIONAL METHOD\n## 5.4 TRRL METHOD","[{\"question\":\"What topics are covered in Part II of the drainage design manual?\",\"answer\":\"It covers basic principles, road planning and locating factors affecting drainage, design standards using return periods, and flood estimation for both gauged rivers and non-gauged basins.\"},{\"question\":\"How does the manual define design standards using return period and design frequency?\",\"answer\":\"It presents the concept of return period and design frequency, then lists applicable design flow return periods for drainage design.\"},{\"question\":\"What methods are used to estimate flood flow for non-gauged basins?\",\"answer\":\"It includes the specific discharge method, the rational method (including time of concentration and rainfall intensity), and the TRRL method with parameters such as initial retention, contributing area coefficient, and lag time.\"}]","Part 2 - Drainage Design - Road Design Manual for Roads and Bridges | PDF",1792800396,348]