Drainage design guide. Published on 25 June 2019 2146 Downloads.

However, designers and architects can often leave drainage to be implemented by specialists in isolation of other design considerations, resulting in costly changes, rework and repairs, operational discomfort and poor user experiences that could have been SDCC Householder’s Guide to Sustainable Drainage (SuDS). Steven Morgenstern, Drainage Design Bureau Chief. ACO world-wide; ACO This revised Drainage Guide was developed to assist Florida NRCS field personnel and others to provide general design guidance and/or recommendations for various drainage systems commonly used in Florida. The primary means of documenting storm drain design is the Department’s storm drain tabulation form shown in Figure 6. After considering the landscape context, the designer should complete a channel assessment, determine the site conditions, causes of channel instability (if present), and the most appropriate design approach. Document/justify tailwater used in the design and provide source of tailwater information. chapter 9 - energy dissipators. Drainage is one of the essential components of roadway design. Chapter 1. 2019 Street Process Manual (2. These easy-to-use routines were developed to make data analysis on drainage sites using LiDAR DEM data to be both easy and available to broader audiences. Institute for Transportation Chapter 2 in this design guide and the Drainage Manual encompass the Department’s general guidance regarding hydrology. The philosophy which guides us internally and protects our customers. Illustrating adequate drainage design together with appropriate cleaning and maintenance procedures within the PRP is the prime objective of this guide. Structural Design Manual. A grading plan is essential for any construction project as it guides the land grading to manage topography and moisture issues process, including cut and fill operations. Items covered in the Water Management Drainage Handbook include specifications, structures, hydraulics, durability, installation, retention/detention systems, general technical notes, sanitary sewer systems, sanitary technical notes and a summary of standard The standards in this Manual provide a basis for uniform design practice for typical roadway drainage design situations. Download the BDE Manual in PDF. Fill the cut around the foundation with two (2) inches of nonporous fill. Check the drainage tubing with a 4-ft. Thus, for proper drainage The Bureau of Design and Environment (BDE) Manual contains the policies and procedures which govern the location, design, and environmental evaluation of highway construction projects on the state highway system. ). 4 DETOURS. Design guidance is provided for the design of storm drainage systems which collect, convey, and discharge stormwater flowing within and along the highway right -of-way. Design guidance is provided for the design of storm drainage systems which collect, convey, and discharge stormwater flowing within and along the highway right-of-way. Sep 1, 2009 · This circular provides a comprehensive and practical guide for the design of storm drainage systems associated with transportation facilities. This Three-D video shows how a flat roof drain should function if installed correctly. every 4 ft. Adjust the gravel base as needed. The Central Office Drainage Section provides hydrologic, hydraulic, stormwater management, and coastal engineering services to. French Drain Guide. Open Channel: Channel Flow Theory - Channel Design - Channel Linings - Connection Permitting and Maintenance Concerns. The standards in this Manual provide a basis for uniform design practice for typical roadway drainage design situations. Jan 24, 2024 · The Department of Transport and Main Roads Road Drainage Manual has been withdrawn and replaced with new supplements to Road Planning and Design Manual - 2nd Edition, Volume 3: Guide to Road Design. ANSI/ASCE/EWRI 12-13 provides guidelines for the design of these systems and covers site analysis, system configuration, drain envelopes, hydraulics and hydrology, structural Guide 1. Nov 28, 2019 · Good drainage contributes to the delivery of sustainable, innovative and resilient buildings, and is essential for our health and wellbeing. Drainage Pipe Guide. Significant revisions and pertinent details are listed below. File Size: 34. chapter 7 - storm drainage systems. 2. Construction Manual. 08. View the GDOT design policy manual, Plan Presentation Guidelines (PPG) and Plan Development Process (PDP) documents. It is an important strategy to manage water flow and avoid excessive runoff. It covers design considerations, climate change, factors of safety, designing for exceedance, network design, construction and more. 6. The entire contents herein is equipped to provide designers of agricultural drainage systems with the best practices suited to their respective Slope surface to grade away from the house. gov. Limit roof area to 25,000 sq. Established as part of the Self and Custom Housebuilding Act 2015, councils are required to maintain a register of people who wish to create their own home and ensure enough plots come forward to meet demand. Complete Drainage Design Guide. Updated Gravity drainage systems are only recommended for flat or low-slope commercial roofs that have a surface area of less than 150m 2 per drainage point. “Principles of Exterior Drainage – Short Course” is a condensed version of the “Principles of Exterior Drainage”. Chapter 3. Hygienefirst. 6 DOCUMENTATION OF DRAINAGE DESIGN Include approvals of deviation from this Manual in the project drainage design documentation, along with supporting justifications. Drainage: 145 acres, moderately sloping, largely farmed on the contour, using conservation tillage. Application guide accompanying the Drainage Manual. Navigate to the BDE Procedure Memorandums to view a complete listing of changes. The drains should be equally spaced and located symmetrically . Procedure Memorandum. Design policies will be eliminated from this list as they are incorporated into the Roadway Design Manual. These are known as Right to Build Registers. It also removes the barrier of having Design a grassed waterway given the following set of conditions: Location: McLean County. Fill the trench and around the bottom of the pipe with another inch of nonporous material, then cover the pipe with three inches of washed rock. chapter 11 - natural stream design. You just need to fill out the form on the right and tell us about your application. Design and check certificate - temporary works type P (May 2022) Design and check certificate - temporary works type S (May 2022) Road safety audits and consultations. 3. North Carolina geospatial information. Specific steps to be taken generally include: (a) Estimating the amount and frequency of storm runoff. Swales should have a 3-to-1 width-to-height ratio, a slope along the longitudinal channel of 2% It may be useful for researchers doing further work in this area as well as those developing improved testing and design procedures and is included because of its historical value. These soils have a moderate rate of water transmission. Nov 17, 2015 · Installing the Drain. roadway drainage design situations. Principles of Exterior Drainage - Quick Review. All supporting calculations and documentation for the on-site conveyance analysis should be presented in Appendix G. 33 and above. Concepts for the design of detention/retention Drainage Design Guide Chapter 2: Hydrology Chapter 2: Hydrology 2-4 . May 31, 2023 · Updated Turnpike Landscape Setback Guide (posted 08/07/2023) Updated GTR Deviation Submittal Letter Template (posted 08/07/2023) Updated Permit Exemption Memo Template (posted 07/27/2023) Updated Drainage Design Kickoff Overview (posted 07/25/2023) Updated Project Checklist for Tolls Design Support (posted 07/24/2023) Use at least two drains where possible. 2 MB. Employee Directory NCDOT contact information. Drainage Design Guide. chapter 5 - roadside ditches & streams. FROM: Central Office Drainage Group . In the design of your project, a drainage consultant can incorporate sustainable drainage systems (SuDS). level to make sure you have at least 1/8 in. 15-01: Policy for Value Engineering; DES 23-04: Final Design; DES 24-01: Policy for Utility Accommodation on State ROW Drainage Design and Erosion Control Manual - PDF. 4 Objectives of Drainage Design Drainage design seeks to prevent the retention of water by a highway and provide for removal of water from the roadway through a detailed analysis considering all pertinent factors. On this form, record items identified by numbers in parentheses on Figure 6. The Drainage Design Guide (DDG) has been revised for the January 202 4 scheduled release date. A Drain that is placed inside a basin makes for the most practical design. The term drainage is defined in several different ways, including the process of removing surplus groundwater or surface waters by artificial means, the manner in which the waters of an area are removed, and the area from which waters are drained. 1120 Cerrillos Rd. The pitch of a roof is the angle at which it slopes. Property Drainage Assessment Checklist. HygieneFirst. If site grade is level or directed toward the house and if space is available on the site, install swales to capture, control, and filter stormwater runoff, allowing it to percolate into the soil on site. The best roof drain is normally one that sits in a basin. Drainage facilities on any highway or street should adequately provide for the flow of water away from the surface of the pavement to properly designed channels. 8 of the Bridge Manual for an overview of bridge scupper policies, procedures, and methods. GENERAL 2. Soils having slow infiltration rates when thoroughly wetted and consisting chiefly of soils with a layer that impedes downward movement of water, soils with moderate fine to fine texture, or soils with moderate water tables. Realizing that drainage design is primarily a matter of sound application of good engineering judgment, it is impossible to give precise rules that would apply to all possible situations which may arise. This is an important factor to consider when designing a flat roof drainage system, as it affects the rate at which water flows off the roof. divided by the 4,600 sq. May 6, 2015 · Guide water away from homes and roadways. 3 Time of Concentration 2. This document provides design standards and guidance for highway drainage systems in Cornwall, UK. morgenstern@dot. ft. Overlap the sock ends after you connect them. The. Chapter 2. Sep 16, 2019 · Make sure the tube slopes to drain the water. Coordinate in advance with the District Drainage Engineer for approval of the design criteria and calculation methods. 1 Design of Enclosed Storm Drain Systems Course 201. 3. Example: 150,000 sq. It can be used to evaluate gray infrastructure stormwater control strategies, such as pipes and storm drains, and is a useful tool for creating cost A strong brand around the world. The pipes are laid on 300mm of clean shingle or possibly broken stone which is graded between 20mm and 50mm. 1 INTRODUCTION. Jan 19, 2024 · Published: January 19, 2024. Design Guides 2. 1. Guidance on holistic design can be found in „Building for Life 12‟, CIRIA Report C635 „Designing for Exceedance in Urban Drainage - Good Practice‟, CIRIA Report C723 „Water Sensitive Urban Design in Councils discouraging self builders from signing up to Right to Build. Oct 30, 2019 · Coverage includes: - Surface and rainwater drainage - Water and energy efficiency through wastewater recycling and reuse, and heat recovery - Cumulative benefits of integrating drainage design Oct 18, 2018 · What is land drainage? Land drain, often known as French Drain, is the name given to flexible coiled pipes which are laid underground to alleviate excess surface water. ensure that Florida DOT provides a safe, economical transportation system that preserves the quality of Florida's environment. It focuses solely on all aspects of exterior drainage, from the identification of the problem to the design and Jul 1, 2001 · This circular provides a comprehensive and practical guide for the design of storm drainage systems associated with transportation facilities. EZ-Drain/EZflow Installation Manual. of roof area. com. This Drainage Design Manual has been prepared as a guide for the hydraulic design of highway drainage facilities. Design side slopes based on site conditions to be stable and meet maintenance requirements. chapter 6 - culverts. This course covers the basics of designing an adequate storm drainage system for a parking lot. Prevent flooding. Detours may be either located on existing streets or constructed with temporary paved or graded lanes. chapter 8 - stormwater storage facilities. This video is certified for ORD version 10. For architectural and engineering specifications, here is our latest product information. 8-1 2. They convey runoff through pipes and large underground storage tanks to store and attenuate surface water. Santa Fe, NM 87505-7500. Los Angeles County Hydrology & Sedimentation Manuals. Nov 11, 2019 · Hence, this is, by far, the most common roof drainage situation. SUBJECT: FDOT Drainage Design Guide – January 2024 . This guide promotes the idea of integrating SuDS into the fabric of development: using the available landscape spaces as well as the construction profile of buildings. 2. Drainage Strategy. These items are discussed in the description following the form. Howbery Park, Wallingford, OXON OX10 8BA Tel: +44 (0) 1491 835381 Fax: +44 (0) 1491 832233 Registered in England No. The most important aspect of a septic tank installation is the drainage field which disposes of the effluent. Whether you are building a new kitchen or upgrading an existing one, this guide is an essential resource for anyone involved in commercial kitchen design. A well-designed drainage system should have: A debris filter at outlet DESIGN Design Procedures System planning Applications, pipe sizing 12 Maximum pipe runs, thermal movement 13 Pipe support, access, offsets 14-15 Design Detailing System connections Connections to drainage 16-17 Connections to waste 18-19 Connections to WCs 20-21 WC manifolds 22-23 Specific design issues Ventilation 24-26 Fire stopping 27 Errata Roadway Design Manual - PDF. Place the pipe in the trench and connect it. Contact. Participants of this course will be introduced to the newest OpenRoads environment and a Workflow for designing two dimensional (2D) Plans, Profiles, and three dimensional (3D) Models for Drainage design, at its most basic, involves the collection, conveyance, treatment, and disposal of water. Larger roofs collect more water that may not drain quickly enough with just a gravity system. METHODS OF DETERMINING DESIGN DISCHARGE 2. Guidelines on Load Posting of Bridges. ACO stands for professional drainage, efficient cleaning and the controlled discharge or reuse of water. Illini Drainage Tools. The contents relating to Eurocodes are printed in green colour in the updated version. Downloadable Guide. 0 MB) Approved Software for use with the Drainage Design Manual (94 KB) Nov 16, 2023 · Understanding and implementing effective grading and drainage strategies are crucial in the intricate dance of construction and environmental stewardship. 6, or 33 drains required. For maintenance and local inquiries, please see the Statewide Maintenance Contacts or Oct 30, 2023 · TO: FDOT Drainage Designers . These are a series of “one-click QGIS processing plugins” being developed at the drainage laboratory, University of Illinois. This document provides guidance on drainage design standards for carriageways and other paved areas in Cornwall, England. Design the drainage for detours on existing streets by using the existing street drainage system while preventing overtaxing of the system on those streets. Chapter 2 in this design guide and the Drainage Manual encompass the Department’s general guidance regarding hydrology. chapter 10 - erosion prevention and sediment control. Swales can be part of an area’s natural landscaping, or they can be created to help ensure proper drainage, minimize runoff or capture storm water. Provide adequate flashing for parapets, openings, walls, joints, skylights, etc. 2 Unit Hydrograph Method 2. Published on 25 June 2019 2146 Downloads. This guide links the design of SuDS with the evaluation requirements of planning in a sequence that mirrors the SuDS design process. AASHTO Drainage Manual. This single-volume set of three standards establishes guidelines for design, installation, and operation and maintenance of urban subsurface drainage systems. Watershed: dominated by Catlin Silt Loam – a dark-colored, well-drained soil. Inadequate Urban Drainage Design Manual: Hydraulic Engineering Circular 22, Third Edition. Mar 4, 2024 · Importance of Grading and Drainage Plans in managing water moves and preventing moisture issues. between these series are notable for smaller storm events (<15-years) but are negligible for larger storm events (i. drainage manual Selection Process Channel Drainage Systems Five channel linear drainage systems are available from Marshalls, designed primarily (though not exclusively) for non-kerbside applications; Max-E-Channel High Capacity Linear Drainage System Birco Linear Drainage System Landscape Drain Slot Drain Traffic Drain Decathlon Step 4 If the channel length Highway drainage is an important consideration in the design of many projects. Thus, for proper drainage Roadway Drainage Design – C03-073 1 Section 1 — Background Provision of sufficient drainage is an important factor in the location and geometric design of highways. HYDRAULIC DESIGN CRITERIAFORDRAINAGE RELATED STRUCTURES 3. both have similar rainfall and intensity results for larger storm events). This video illustrates the perfect drain on a roof. Drainage report for planning applications in full compliance with local and national regulations at competitive prices. Sewer Design Manual. These systems effectively bypassed the natural 4. Siphonic Drainage. Use the drainage guide or other local information to determine side slope limits for specific soils and/or geologic Definitive Drainage Guide. Using swales, ponds, rain gardens, permeable paving, and green roofs in your designs, you can get multiple benefits. Capture rain water for reuse. Install a drain at most 50 ft. Most drain projects are unique, with different watershed conditions and site constraints. Every domestic building should be provided with a drainage system to remove surface water from paved surfaces, such as an access route that is suitable for disabled people, without endangering the building or the health and safety of people in and around the building. 8 - Scupper Placement Nov. 0 percent. Slope of the Waterway reach: 2. Aug 28, 1987 · SECTION 11 - DRAINAGE DESIGN CRITERIA 1. Oversize/Overweight Permits Annual, single trip and superload permits. of slope per foot of tubing (1/2 in. The aim is to provide a basic working knowledge of hydrology and hydraulics to hydraulics engineers, with an emphasis on basic design elements - it is not intended for guidance on more The 2019 City of Dallas Street and Drainage Design Manuals and Street Process Manual are in effect for projects beginning design on or after October 1, 2019. The hydraulic designer will provide a Drainage Design Report to accompany all phase submittals (signed and sealed for the The Illinois Drainage Guide is a website that serves as a technical reference platform for providing both educational and practical solutions to drainage related issues within the state of Illinois. Adequate drainage is more than a necessary evil, it is a major influence on proper water management. 1-1. Step 4: Divide total roof area by area found in Step 3 to obtain the number of drains required. 8 MB) 2019 Drainage Design Manual (9. Survey Manual. 2562099. Guidelines for establishing specific policies and procedures for the design of highway drainage facilities are provided in this manual. Consider geography, budget and use for the roof to determine The primary means of documenting storm drain design is the Department’s storm drain tabulation form shown in Figure 6. These recommendations include depth, spacing, and channel side slope for surface drain main or lateral and surface drain field ditch, and tile The ultimate goal is to ensure economic design, constructability, and sustainability of NMDOT drainage structures. pdf. Vendor Directory Searches Certified and prequalified firms. Dec 2, 2020 · 3. This guide offers step-by-step instructions and expert advice to help readers design a drainage system that meets their specific needs and requirements. Stormwater Pollution Abatement Handbooks and Publications. 4 Flood Routing 3. 505-231-7688. Highway Safety Design Standards Manuals: Part 1 – Road Safety Design Manual and Part 2 – Road Signs and Pavement Markings Manual. Project Delivery Manual. steven. 2 Runoff Curve Number 2. For best results, the roof should have a slope of at least 1/4 inch per foot to ensure proper drainage. Hydrology: Drainage Data - Procedures Selection. Location: Attention: Drainage Design Bureau, Room 219. The soakaway system is made up of a series of 100mm perforated pipes laid to a uniform pattern and to a gradient of 1-in-200. Direct water to gardens. pdf (size 4 MB) Traditional surface water drainage systems are typically “Hard Engineered” solutions used in drainage design. Updated 10-2023 Policies. If you have any questions, The Guide to Sustainable Urban Drainage Techniques is an instrument for achieving the Sustainable Development Objectives (ODS), established by the United Nations Organization (UNO), in accordance with the goals of Objectives 11 and 13: to implement policies and integrated plans for the inclusion, resource efficiency, mitigation and adaptation to climate change, resilience to disasters; and Example: For a 4" hourly rainfall and 4" leader, each drain can handle 4,600 sq. See new supplements Part 5: Drainage - General and Hydrology Considerations, Part 5A: Drainage - Road Surface, Networks, Basins and Subsurface, and This circular provides a comprehensive and practical guide for the design of storm drainage systems associated with transportation facilities. This information also is available on the FDOT Drainage web site. The term “detour” is defined in FDM 240. equals 32. 01. chapter 4 - hydrology. From there, the flat roof system you choose will determine the materials you apply. Introduction: Background - Purpose - Revisions - Definitions of Terms and Acronyms. 1 4 1 Drainage Design Process 4 1 4 2 Drainage Design Considerations 4 1 4 3 Defining a Project 5 1 4 4 Sustainable Design Guidelines 5 1 4 5 Pre-Development Meeting 5 1 4 6 Design Software 5 SECTION 2 Jul 1, 2020 · 801. 8 Bridge Scupper Placement This design guide contains a procedural outline and example for scupper placement. This will save time and energy when building extensions too. We will also be looking at rainwater drainage systems and drainage building regulations. e. It is ACO´s commitment to ultimate hygienic performance. File Name: 2013_za_drainage_manual_application_guide. Jun 25, 2019 · 2013 - South Africa - Drainage Manual Application Guide. They are corrugated and can typically flex 90 degrees per 1m, and come in either perforated or unperforated coils, available from JDP in sizes varying from 60mm-160mm in 25m Jul 25, 2023 · Roof Pitch. FHWA Publication Number: NHI-10-009; Publication Year: 2009; Last Errata Date: 08/22/2013 Underneath the basics, flat roofs are usually constructed with a ceiling, nailed to joists which support a deck (usually wood in residential construction), a vapor barrier, insulation and a roof board. Make certain that the holes of each section are facing up. PDS includes all rainfall amounts for specified durations above a predefined - Our comprehensive drainage design services comply with building regulations, Sewers for Adoption: A Design and Construction Guide for Developers, lead local flood authorities guidance and the CIRIA SuDS Manual. This circular provides a comprehensive and practical guide for the design of storm drainage systems associated with transportation facilities. Moderately High Runoff Potential. For the period from 1 June 2013 to 31 December 2014,the adoption of updated version is optional for public works civil While it’s a complicated topic, it is worth understanding underground drainage layouts to assist with access for repairs. Injury and Illness Prevention Program. 1 Rational Formula 2. per weir opening. from the edge of a valley. Stormwater drainage design is an integral component in the design of parking lots. Realizing that drainage design is primarily a matter of sound application of good engineering judgment, it is impossible to give precise rules that would apply to all possible situations may arise. Frequency of Grade Reversals or Cross Drains Source: Forest Service Trails Handbook 2309. It outlines the benefits May 3, 2024 · chapter 3 - drainage plan requirements. This guide contains all you need to know for any drainage design project. Methods are presented for evaluating rainfall and runoff magnitude, pavement drainage, gutter flow, and drainage inlets. Those roofs benefit from siphonic drainage systems. How to Unclog a Toilet. See also Section 2. 18, Chapter 3, Trail Preconstruction & Construction Grade (percent) Material Type 2 4 6 8 10 12 15 Loam 350’ 150’ 100’ 75’ 50’ * * Clay-Sand 500’ 350’ 200’ 150’ 100 The curriculum was developed within the FDOTCONNECT Workspace to provide sample exercises for many of the Drainage Tools on a sample project data set. Note - The updated version incorporates updating for migration from British Standards to Eurocodes in respect of structural design. Principles of Exterior Drainage - Quick Review - En Espanol. The downloadable slot drain guide is a complete overview of the product including specifications and installation instructions. 1005. Keep the distance between drains to at most 200 ft. from a roof edge. This Three-D video shows how an ideal flat roof drain should function. nm. Approved Products and Materials Lists. Design guidance is provided for the design of storm drainage systems which collect, convey, and discharge stormwater 10. Urban Drainage Design Manual Third Edition. A good drainage system will reduce the risk of detrimental waterlogging to acceptable levels and help return soils to field capacity after wet weather. 7. In simple terms, they are generally shallow ditches that have gently sloping sides. Inclusion of Bridge Aesthetics in all Bridge Plan. Drainage criteria and design outlined in this manual reflects the maximum standard achievable that is based on new project development for effect of any overland flows from adjacent sites. It outlines general principles, factors for design consideration like climate change and safety, and guidance on specific design elements like minimum pipe depths, catchpit positions, and connections to open water. SuDS are used to manage water runoff from sites by mimicking natural processes. which Thus, for proper drainage design, we must preserve flexibility to account for varying site conditions What is field drainage? Well-maintained field drainage systems help remove excess soil water (held in the upper soil horizons) and can be used to control a water table. This comprehensive guide delves into the Oct 3, 2003 · Manual for the Design of Roof Drainage Systems A guide to the use of European Standard BS EN 12056-3:2000 R W P May Report SR 620 March 2003 Address and Registered Office: HR Wallingford Ltd. 1 Rainfall - 2. 1 Time of Concentration Chapter 2 (Hydrology) defines and provides methods to calculate the time of Feb 27, 2024 · EPA's Storm Water Management Model (SWMM) is used throughout the world for planning, analysis, and design related to stormwater runoff, combined and sanitary sewers, and other drainage systems. Interim Guidelines on the Eligibility Processing for all Field Offices Connected to the CWR. Refer to the FDOT Drainage Manual and Chapter 6 of the Drainage Design Guide for guidance. For most dwellings, you’ll find that gutters range in size from approximately 100mm diameter to 150mm diameter (assuming gutters with a ‘half-round’ section profile), and downpipes range from approximately 60mm diameter to 90mm diameter (assuming circular downpipes). File Type: application/pdf. This is ADS’ Water Management Drainage Handbook, which details technical information about ADS products and the products’ usage. Drainage Design and Drain Dips anuary 201 ersion Figure 3. This process should also form part of the Design Risk Analysis for any building design. 1 Time of Concentration Chapter 2 (Hydrology) defines and provides methods to calculate the time of Sustainable Drainage: Design & Evaluation Guide. It is an integral part of any architectural project, influencing the longevity, functionality, and even the aesthetics of the building. Drainage design guide (August 2017) Soakaway Checklist (September 2021) Open the Prerequisite Programme (PRP). 2 Surface water drainage of paved surfaces. More information. 5 MB) 2019 Street Design Manual (45. Jun 28, 2024 · Enhancing Amenities and Biodiversity. Where a low-flow or two-stage channel is planned, use the design process in NRCS National Engineering Handbook (NEH), Part 654. The guidance is intended to provide consistency in highway Along with extensive technical information, the Design Guide walks engineers through the complex LRFD design process established by AASHTO for corrugated plastic pipe, while the Installation Guide and Design Calculation Guide are invaluable for contractors and installers. 2006 Page 2. The design should work with the contours of the land to manage exceedance flows safely. Principles of Exterior Drainage - Full Course. Road safety audits (August 2012) Consultation on developer led proposals (September 2015) Drainage. py zd er bo sy sp jx sx cc ev