Technical guide - Roadway water management
This technical guide on roadway water managementproposes a methodical approach to the technical design ofstructures to accommodate natural flows, for surface drainageof the platform and for internal ground drainage.
This guide is intended for project owners and maincontractors and for design offices and consultants concernedin the design of water management structures for new roadprojects and in rehabilitation studies for existing roads.
Road construction hydrology covers the re-establishment of natural flows, the drainage of roadways, drainage and the control of road pollution. The recommendation on road improvements of 1982 dealt essentially with the first two fields. The collection of guides "Water and road construction" deals with the protection of water resources and aquatic environments in the context of road infrastructure.
A working group made up of hydraulic experts was set up by Sétra to collect up-to-date knowledge in the field of hydrology and take account of environmental protection-related impacts.
This work took shape in a guide in three main sections :
• the technical design of structures;
• studies;
• the quality procedure.
General technical appendices give calculation examples and ABAC calculation charts to be used.
It was devised to meet the needs and expectations of prime contractors. Its primary purpose is as a tool that assists in the design of drainage structures for new road projects and improvement planning studies on existing roads.
Contents
The Sétra supports the public owner ............................................................................... 2
The Sétra, producer of the state of the art....................................................................... 2
The Sétra, a work in partnership ....................................................................................... 2
Contents................................................................................................................................ 5
Preamble .............................................................................................................................. 7
1 - Technical design of structures ..................................................................................... 8
1.1 - Re-establishment of natural flows (catchment areas < 100 km2)......................... 8
1.1.1 - General principles.................................................................................................... 9
1.1.2 - Determination of the project flow ........................................................................ 11
1.1.3 - Design of hydraulic structures ...............................................................................18
1.1.4 - Maintenance and operation of the hydraulic structures ................................. 19
1.2 - Surface drainage of the platform...............................................................................20
1.2.1 - General principles.....................................................................................................20
1.2.2 - Nature and function of systems .............................................................................20
1.2.3 - Choice of drainage structures and hydraulic design calculation ........................ 26
1.1.4 - Maintenance and operation of the structures [11] .............................................. 26
1.3 - Road structure drainage...............................................................................................27
1.3.1 - Definition ....................................................................................................................27
1.3.2 - Who does what? ........................................................................................................ 27
1.3.3 - Summary of the effects of water on the road......................................................... 27
1.4 - Controlling road pollution............................................................................................ 27
1.4.1 - Definition ................................................................................................................... 27
1.4.2 - Who does what? ....................................................................................................... 27
1.4.3 - Summary of risks and challenges .......................................................................... 28
2 - Sequence of studies ...................................................................................................... 29
2.1 - Preliminary studies...................................................................................................... 29
2.1.1 - Hydraulics* ............................................................................................................... 29
2.1.2 - Protection of Water Resources................................................................................ 29
2.2 - Outline Preliminary Project (APS) studies ................................................................. 30
2.2.1 - Choice of scales for the plans of the routes studied ............................................ 30
2.2.2 - Road surface drainage at the Outline Preliminary Project (APS) study stage.....30
2.3 - Project studies .............................................................................................................. 33
2.3.1 - Height setting constraints ........................................................................................ 33
2.3.2 - Validation of the general principles......................................................................... 33
2.4 - Water Law Dossiers (DLE) or water police [police de l’eau] dossier ....................... 35
2.4.1 - At the project study stage ......................................................................................... 35
2.4.2 - At the Outline Preliminary Project (APS) level ........................................................ 35
3 - Study quality approach ................................................................................................... 36
3.1 - Notions of process and progression, of inputs, outputs and tasks......................... 38
3.1.1 - Process ........................................................................................................................ 38
3.1.2 - Progression ................................................................................................................ 38
3.1.3 - Required "inputs" and expected "outputs" ............................................................. 39
3.1.4 - Main tasks .................................................................................................................... 39
3.2 - Issuing an order .............................................................................................................. 41
3.2.1 - General principles......................................................................................................... 41
3.2.2 - Progression of studies ................................................................................................. 41
3.3 - Traceability of choices/decisions, archives.................................................................... 55
3.4 - Validating the production................................................................................................ 55
4 – General technical appendices .......................................................................................... 56
4.1 - General elements of hydrology ...................................................................................... 56
4.1.1 - Rainfall data.................................................................................................................... 56
4.1.2 - Numerical example of application for the calculation of a project flow of a natural catchment area ...................................................................................................................................................... 58
4.2 - Elements of general hydraulics ....................................................................................... 65
4.2.1 - On the theory of flows .................................................................................................. 65
4.2.2 - ABAC design charts for small hydraulic structures for re-establishing natural flows............................................................................................................................................ 74
4.2.3 - Constructional arrangements and protection of hydraulic structures ................... 84
4.2.4 - Dimensioning of a hydraulic structure for re-establishing natural flows - application example....................................................................................................................................... 86
4.2.5 - Surface drainage of the platform - calculation method ............................................ 94
4.2.6 - Surface drainage of the platform - hydraulic calculations - application examples 97
4.3 - Glossary.............................................................................................................................. 105
4.4 - Abbreviations and symbols ............................................................................................. 108
Abbreviations (French) .............................................................................................................. 108
Symbols........................................................................................................................................ 108
4.5 - Table summarizing principle formulae ........................................................................... 110
4.6 - Bibliography (non-exhaustive list)................................................................................... 112
Technical documents:................................................................................................................. 112
Regulatory texts: ........................................................................................................................ 112
For information .......................................................................................................................... 112
