Guidelines - IMESA - Low Cost Road 09Jun2005rev

I.M.E.S.A. Municipal Guidelines

SECOND Edition MG 1

GUIDELINES FOR DESIGN, CONSTRUCTION AND MAINTENANCE OF LOW COST ROADS AND ASSOCIATED DRAINAGE FOR FURTHER INFORMATION PLEASE CONTACT J PIETERSEN – TEL. (031) 7182404 ÉTHEKWINI MUNICIPALITY P O Box 244 Pinetown 3600

APRIL 2006 Edition MG 1. pp 1 – 18, Durban, Durban, South Africa, 2006

GUIDELINES FOR DESIGN, CONSTRUCTION AND MAINTENANCE OF LOW COST ROADS AND ASSOCIATED DRAINAGE CONTENTS Chapter

Description Page

1.

INTRODUCTION .......................... ........................................ ........................... ........................... ................. ... 1

2.

......................................... ................... ..... 2 SOCIO-ECONOMIC CONDITIONS...........................

3.

ROAD CATEGORIES ........................... ......................................... ........................... ....................... .......... 2 3.1 Minor arterials arterials ...................... .................................. ....................... ...................... ....................... .......................3 ...........3 3.2 Residentia Residentiall Access Access Road Roads s ...................... ................................. ....................... ....................... ...............3 ....3

4.

SUBGRADE CONDITIONS .......................... ....................................... ........................... ................. ... 4 4.1 Geotechnical Investigation................ Investigation.... ......................... .......................... .......................... .................. .....4 4 4.2 Material Material Depth ..................... ................................. ....................... ...................... ....................... .......................5 ...........5 4.2.1 Minor Arterials..................... Arterials........ .......................... .......................... ......................... ........................ ............ 5 4.2.2 Residential Access Roads ......................... ............. ......................... .......................... ..............5 .5

5.

GEOMETRIC ROAD DESIGN........................... ......................................... .......................... ............ 5 5.1 Road Cross Section........... Section ........................ .......................... .......................... .......................... .................... .......7 7

6.

PAVEMENT DESIGN ........................... ......................................... ........................... ....................... .......... 9 6.1 Minor Arterials.................... Arterials........ ......................... .......................... .......................... .......................... .................... .......9 9 6.2 Residentia Residentiall Access Access Road Roads s ...................... ................................. ....................... ....................... .............10 ..10

7.

STORMWATER DRAINAGE DESIGN ............................ ........................................ ............ 10 7.1 Stormwater Drainage Design............ Design ......................... .......................... .......................... ................ ...10 10 7.2 Return Period..................... Period......... ......................... .......................... .......................... .......................... .................. .....14 14

8.

QUALITY CONTROL.......................... ....................................... ........................... ........................ .......... 14

9.

........................................ ........................... ............................ .......................... ............ 15 SAFETY ...........................

10.

ENVIRONMENTAL ............................ ......................................... ........................... ........................ .......... 15

11.

........ ......... ......... ...... 15 ROAD AND STORMWATER ASSET MAINTENANCE ....

12.

REFERENCES........................... ......................................... ........................... ........................... ................. ... 17

13.

ACKNOWLEDGEMENTS........................... ........................................ ........................... ................. ... 18

1. INTRODUCTION The purpose of this document is to provide municipalities with guidelines for design, construction and maintenance of low cost/volume roads and associated drainage. Low volume roads are defined as minor arterial or residential access roads which carry less than 500 vehicles per day, including up to 20 % commercial vehicles and non-motorized traffic. This document is not intended as a design manual, rather it seeks to collate available design guidelines with experience gained over years into a set of guidelines which are appropriate for given circumstances taking cognizance of geographical, geotechnical or socio-economic factors. The emphasis is on the improving of existing conditions in informal settlements or townships, thereby improving quality of life, in a most costeffective manner. It is also important to ensure that projects are implemented as part of a phased development; i.e. very basic improvements can be implemented first, with further enhancements added as the desired level of service increases when more funds become available. Low cost roads should be constructed to levels where they can effectively be upgraded. The emphasis of the Municipality should be to optimize their expenditure on roads, drainage and maintenance over a number of years, in accordance with a strategic road infrastructure maintenance management system or plan. (An example of such a plan, referred to as RIMMS, is available from the eThekwini Municipality on request from the Maintenance Management). ( 1 ) Such a plan should also include planned improvements to the road drainage as to reduce risk of flooding of properties which could result in damage to property and loss of life. The provision of services to underprivileged communities is a rewarding task, but must be coupled with a vision of how the “improved standard of life” can be maintained. It is therefore imperative to have a strategic road infrastructure maintenance management system or plan, which will protect the investment as well as provide local employment and a sense of ownership to the community.

1

2. SOCIO-ECONOMIC CONDITIONS These guidelines are supportive of sustainable poverty alleviation programmes for example the Expanded Public Works Programme (EPWP), structured in the interests of the poor. A substantial amount of the overall annual budget allocation must be channeled towards the implementation of the EPWP to: •

•

•

Create employment opportunities for the unemployed Develop skills within communities through EPWP on-the-job skills programmes Capacitate Small Medium Macro Enterprises (SMME’s) to execute EPWP work within communities by facilitating the transfer of sustainable technical, managerial and financial skills.

The use of Labour Intensive methodology in construction and maintenance will significantly reduce poverty within a City or Town and give access to Government Grant Funding. Since not all projects are 100% conducive to labour intensive construction methods, each should be assessed on its merits and justification provided if it is considered that labour intensive construction methods cannot be implemented on a particular project.

3. ROAD CATEGORIES For the purpose of this document, two street categories are considered as basic access streets: •

Minor arterials (Bus routes) and

•

Residential Access roads

2

The following table serves as a guide to the road design:

TYPICAL ROAD CHARACTERISTICS ( 2 ) Minor Arterials

Residential Access Roads

Description and Function

Low Order Mixed Pedestrian and Vehicle Route

Pedestrian and vehicle access route

Level of service (LOS)

Moderate to Low

Low

Traffic (vehicles per day)

>75 < 500