Greendale Pipeline

HOWICK WATER SUPPLY SYSTEM

MILLS FALLS TO HOWICK WATER WORKS

AUGUMENTATION PUMPING MAINS

(GREENDALE PIPELINE)

DESIGN REPORT

UMGENI WATER

310 Burger Street

Pietermaritzburg 3201

JULY 2006.

TABLE OF CONTENTS

Page

INTRODUCTION 3

GENERA 3

BACKGROUND AND PURPOSE OF NEW MAINS 3

TERMS OF REFERENCE 3

LOCALITY 3

SITE DESCRIPTION 4

TOPOGRAPHY AND GEOLOGY 4

CLIMATE 4

WATER DEMAND 4

PRESENT AND RECENT WATER DEMAND 4

FUTURE (DESIGN) DEMAND 5

EXISTING (SUPPLY) WORKS 6

SOURCE 6

TREATMENT PLANT 7

PUMPING PLANT AND MAINS 7

PUMPING PLANT 7

PUMPING MAIN 7

STORAGE 7

DISTRIBUTION 7

PROPOSED WORKS 7

SOURCE 7

PUMPING PLANT AND MAINS 7

PUMPING PLANT 7

PUMPING MAIN 8

STORAGE 8

DISTRIBUTION 8

VALVES 8

HYDRAULIC ANALYSIS 9

TENDER DRAWINGS 9

COST ESTIMATE 10

COST OF WATER 10

RECOMMENDATION 10

APPENDICES 11

1. INTRODUCTION

1.1. General

This design report describes the proposed engineering works to upgrade a 2,5 km section of the Mills Falls to Howick Reservoir Complex pumping main and upgrading of the existing pumps. The design is based on the projected demands derived from new housing developments in the Howick area and the ever increasing urban population in the town. It is proposed to install a 400NB steel pipe to upgrade the aged section of the rising main from the old Greendale pump station to the Howick Reservoir Complex, which is located on the old Howick Water Works premises. It is also proposed to replace the existing old pumps with new a pump. The estimated total cost of the project was R 6, 44 million.

1.2 Background and Purpose of New Mains

The section of the rising main to be upgraded consists of a 300NB AC pipeline that was installed in 1980. It used to convey unstabilised raw water from Midmar dam to the old Howick Water Works until the Water Works were decommissioned in 1997. There have been recent reports of operational problems experienced,...