2020
RDM4702 RETICULATION
DESIGN MANAGEMENT IV
MOLEBOGENG MATHIBEDI
Unique Number: 533203
8/28/2020
ASSIGNMENT 2: RDM4702 PROJECT 2020
BTECH STRUCTURAL ENGINEERING
UNISA
RDM4702 RETICULATION DESIGN MANAGEMENT IV
AUTHOR: MOLEBOGENG MATHIBEDI
DECLARATION:
I Declare that this assignment is my own work and that all sources
quoted have been acknowledged by appropriate references
SIGNED: M MATHIBEDI
DATE: 18 AUGUST 2020
PLACE: NINAPARK, PRETORIA SOUTH AFRICA
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RETICULATION DESIGN AND MANAGEMENT IV PROJECT 2020
The Preliminary Planning, Design and Cost Estimate for the CIVIL ENGINEERING STORMWATER SERVICES
for an upmarket residential township
BY MOLEBOGENG MATHIBEDI
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ACKNOWLEDGEMENTS
I would like to thank God, my Grandparents, my Mother and my Family who supported me throughout and
made who I am today possible and have been there through the rough and the great times in my career and
studies. I would also like to thank my Mentor and Senior Boyce Sonti whom in the brief time spent together
taught me the basics of Roads and Stormwater in Civil 3D and SSA.
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SYNOPSIS
EXECUTIVE SUMMARY OF REPORT
Ruimsig Country Estate which is an upmarket township in the Gauteng, South Africa, currently lacks a
stormwater drainage system. This project presents a preliminary design for a stormwater drainage system in
for the upmarket township. Such a design can serve as a model that can be implemented to the other areas
in the country. The design of this collection system involved investigating hydraulic modeling and analysis,
alternatives for drainage system and cost estimates for the system. A gravity collection system should be
designed based on recommended specifications.
KEY WORDS:
Stormwater Services;
Runoff;
Preliminary Designs;
Cost Estimation;
Critical Path;
Design Standards;
Ruimsig Country Estate;
Pipes;
Manhole;
Catchments;
Glossary
Stormwater Drainage System: All the Facilities that are used for the collection, conveyance, storage,
treatment, usage and disposal of Run-Off from a drainage area to a specified point.
Runoff : The water which constitutes streamflow that may reach the stream channel or kerb inlets.
Stormwater Outfall : The Point at which runoff discharges from a conduit.
Drainage Area: The Part of the catchment that is above a specified point that contributes to the runoff at
that point.
Critical Path: The Longest Path the water will travel within the pipes to the discharge point.
Kerb: A stone edging to a pavement or raised path.
Design Period: The length of time a structure will be expected to have a useful life(Structure Life Span)
Abbreviations
I – RAINFALL INTENSITY
S – SLOPE
Q - PEAK FLOW
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ADF - AVERAGE DAILY FLOW
PDF - PEAK DAILY FLOW
PWF - PEAK WET WEATHER FLOW
TABLE OF CONTENTS
SYNOPSIS .................................................................................................... 4
Glossary ...................................................................................................... 4
ABSTRACT.................................................................................................... 6
INTRODUCTION.............................................................................................. 6
1.
PROBLEM STATEMENT: ................................................................................ 8
2.
AIM AND OBJECTIVES .................................................................................. 8
3.
SCOPE & LIMITATIONS ................................................................................. 8
4.
STAKEHOLDERS ........................................................................................ 9
5.
SUMMARY OF CHAPTERS .............................................................................. 9
6.
TECHNICAL ASSESSMENT: ............................................................................ 10
7.
ENGINEERING DESIGN STANDARDS .................................................................. 13
DISCUSSIONS ............................................................................................... 22
RECOMMENDATIONS ...................................................................................... 23
CONCLUSION ............................................................................................... 23
REFERENCES ................................................................................................ 24
APPENDICES .......................................................................................................................... 25
Appendix 1: Survey Layout .................................................................................... 26
Appendix 2: DTM Model & Ground Profile ............................................................. 27
Appendix 3: Stormwater Layout............................................................................. 28
Appendix 4: Catchment Layout.............................................................................. 29
Appendix 5: Design Calculations ........................................................................... 30
Appendix 6: Schedule of Preliminary Quantities based on the Preliminary Design in
accordance with Standardized Specification SABS1200 ....................................... 31
Appendix 7: Cost Estimate .................................................................................... 32
Figure 1 - LOCALITY MAP – RUIMSIG, KRUGERSDORP ........................................................................................... 7
Figure 2-ORTHOGRAPHIC MAP- RUIMSIG, KRUGERSDORP .................................................................................... 7
Table 1 – DESIGN GUIDELINE..………………………………………………………………………………………………………………14
Table 2 – HYDROLOGY………………………………………………………………………………………………………………………….15
Table 3 – HYDRAULICS……………………………………………………………………………………………………………………….…16
Table 4 – PROPOSED WEATHER STATION……………………………………………………………………………………………….18
Table 5– WATER SYSTEM DESIGN PARAMETERS…………………………………………………………………………………….20
Table 6–ADF PER SINGLE FAMILY DWELLING UNIT………………………………………………………………………………..20
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ABSTRACT
This Design report is based on the RDM4702 IV project. The project is based on the design of the
stormwater services for an upmarket residential township in Ruimsig, Gauteng.
INTRODUCTION
DorDave Engineering Consortium has been appointed as Consulting Engineers to do the preliminary
planning, design and estimate the cost of civil engineering stormwater services for an upmarket residential
township in Ruimsig Country Estate, Krugersdop.
PROJECT DESCRIPTION:
Requests for Proposals: Professional Services Ruimsig Country Estate Stormwater Drainage System.
Contract No: CJ5502.
Designs Proposals from Civil and Structural Engineering Consultants to Design and Implement Stormwater
Services for the Estate.
The Estate experiences constant flooding during the rainy season due to lack of drainage infrastructure, as a
result the existing road structures are damaged due to erosion.
This Preliminary Design Report (Stormwater) for this project; serves as a summary of the preliminary design
stage in which the site conditions were assessed, and the design concepts and parameters were
determined. The main aim of this report is to present the recommendations from the preliminary design
processes to enable better decision-making in everything from budgets to management plans. This report is
an important key to time-effectiveness, cost-effectiveness and environmental responsibility.
This report marks the end of the Concept and Viability stage that was preceded by inception and technical
assessment report and project programme plan.
DorDave Engineering Consortium representatives visited the site on the 5th August 2020 to perform an
initial storm water infrastructure assessment and thorough site assessment. The assessment findings are
detailed under the Technical Assessment Section.
It should also be noted that DorDave Engineering Consortium has already submitted a detailed Project
Programme and Inception report to fast track the deliverables and save valuable time given the urgency of
the project.
Project Location
Ruimsig Country Estate is located approximately 5km north east of Krugersdorp along M47 project
coordinates (Latitude: 26° 4’13.48’S, Longitude 27° 50’ 50.14’E)
See Below Locality Map and Orthographic Map
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FIGURE 1 - LOCALITY MAP – RUIMSIG, KRUGERSDORP
FIGURE 2-ORTHOGRAPHIC MAP- RUIMSIG, KRUGERSDORP
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1. PROBLEM STATEMENT:
Ruimsig Country Estate experiences constant flooding during the rainy season due to lack of drainage
infrastructure, as a result the existing road structures are damaged due to erosion. It is required to do
the preliminary planning, designing and estimating of the cost of civil engineering stormwater services
for an upmarket residential township. It is required to design a stormwater collection system for the
area given in the layout.
2. AIM AND OBJECTIVES
A preliminary design report with the following main objectives:

Proposed layout for the stormwater system of the township

A planning & design criteria schedule for each infrastructure, indicating all relevant design criteria
used

Design Calculations

Preliminary Designs (Long Sections, Cross Section, Catchments, Subcatchments, Details etc)

A schedule of preliminary quantities based on the preliminary design in accordance with
standardized specification SABS 1200

Cost estimate of the township infrastructure based on the schedule in 2.4 above, using current
average contract prices for the items scheduled.
3. SCOPE & LIMITATIONS
The project scope is to provide full scope of services of stage 2 Preliminary Design Stage, as per latest
ECSA guideline which is basically the Preliminary planning, designing and estimating of the cost of civil
engineering stormwater services for an upmarket residential township. Assume data as required. BUT
contacting or obtaining any information or data from any government or local municipality is
forbidden. Clearly define and explain all design assumptions. Numbers are mandatory.

The design must allow only runoff from the contributing catchments

It is required to make use of appropriate computer software to assist with design (Civil 3D,Design
Rainfall Estimation in South Africa, Excel Programmes etc)
Main Focus:
Prepare of Preliminary Design Report
Prepare Preliminary Designs
Prepare Schedule and Cost Estimates for the Project
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4. STAKEHOLDERS
The following bodies have been identified as suitable stakeholders for this project:
Mogale City Local Municipality:
Mogale City Local Municipality is the official sponsor and is responsible for funding the entire project.
As the Client, the Mogale City Local Municipality will have approval power over any decision regarding
the project
Residents and Communities around Ruimsig Country Estate, Gauteng:
The construction stormwater drainage systems in Ruimsig will help reduce the amount of flooding and
improve safety for commuters and residents.
DorDave Engineering Consortium:
DorDave Engineering Consortium is the appointed Consultant for the project; it therefore has the
responsibility to provide a suitable solution in line with good practice measures / guidelines as well as
the legislation in force
Sub-consultants:
The Sub-consultants are to service the project during the entire planning phase; this will include
providing best advice on Environmental matters, best flood control measures and Occupational Health
and Safety related matters.
Project Team:
The project team’s responsibilities are to run and facilitate the project activities that include feasibility
study, site assessment and preliminary designs.
5. SUMMARY OF CHAPTERS
The Chapters covered in this review report will be as follows:

Technical Assessment

Engineering Design Standards

Preliminary Designs and Layout

Design Calculations

Cost Estimates

Discussions

Recommendations

Conclusion

References
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6. TECHNICAL ASSESSMENT:
6.1 Topographical Survey
The City of Johannesburg cadastral has been adopted to indicate the boundaries of residential and
commercial properties as well as any geographical features in Ruimsig, Johannesburg. A detailed
topographical survey has been provided along with a DTM file for the project as to show all existing
topographical features. The Surveyor shall be call upon before and during construction to confirm
existing invert levels of any channels or culverts and establishment of fall slopes.
6.2 Geotechnical Investigation
DorDave Engineering Consortium (Pty) Ltd appointed Lufuno Lenvelo Consultants to undertake a
Geotechnical Investigations in Ruimsig Country Estate to confirm the general geotechnical and
geological site conditions, and provided recommendations on the suitability of material for bedding
and backfill, excavation and compaction requirements, foundations and bearing capacity etc. The
investigations were done and a Geotechnical Technical Desktop study was provided. A summary of the
findings is outlined below:
The following typical soil profile should be anticipated:
Transported (Hillwash)
Typically this area will be blanketed by a transported colluvium that is likely to exist as a medium
dense, sandy to clayey silt, with may contain abundant rounded and sub-rounded cobbles and small
boulders.
From experience it is unlikely that this horizon will exceed 500mm in thickness. It is likely that the
horizon will exhibit a low to moderate heave potential and could be expected to classify as G7 to G8
construction materials in terms of TRH14.
Pedogenic
Due to the relatively impermeable nature of the underlying residual soils it is likely that development of
a pedogenic horizon in the form of a ferricrete is likely to occur across the site. Typically this horizon
develops below the transported horizon and is most clearly observed in the upper residual soil horizon.
The ferricrete horizon can vary from a loose nodular material to a hardpan or honeycomb horizon of
very soft rock consistency. Typically the horizon varies in thickness from 100mm to <500mm.
Laboratory tests on these soils will most probably indicate low plasticity and this material would
generally classify as a G7 material on a TRH14 classification system.
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Residual Sandstone
This horizon represents the residual soils which have formed as a result of insitu weathering of the
sandstone bedrock. In this area the material is likely to occur as yellow brown, mottled grey brown,
dense becoming very dense, relic fissured, silty sand with fine gravels and scattered cobbles. Typical
thicknesses for this horizon range from 500mm to 1500mm. Laboratory tests on these soils will most
probably indicate low plasticity and this material would generally classify as a G7 material on a TRH14
classification system.
Residual Shale
Typically the residual shales develop as sandy to clayey silt, which may contain abundant closely packed
cobbles and small boulders. Typical thicknesses for this horizon range from 500mm to 1500mm.
Laboratory tests on these soils will most probably indicate medium plasticity and this material would
generally classify as worse than G10 material on a TRH14 classification system.
The CBR values of the soil layers are 15.5% at 0.6m. DCP results deeper than 1.5m cannot be relied on
due to increased frictional resistance of the testing rods hence the tests were limited to 1.0m. The
maximum bulk density of the residual material of shale is 1768kg/m³ with an optimum moisture
content of 19.5%. The maximum soaked CBR value is 10% at 95% MODAASHTO on a residual material
of shale. In terms of the Unified Soil Classification system the material of residual shale is classified as
‘GC-CL’ soil type, these being clayey gravels, gravel-sand clay mixtures to inorganic clays of low to
medium plasticity, gravelly clays, sandy clays, silty clays and lean clays. Its grading modulus is 0.55
which reflects its fairly fine nature.
6.3 Existing Services:
Existing Water and Sewer Reticulation:
There are 75 mm and 160mm uPVC diameter municipal water lines running along the roads in the area.
Existing Fibre Services:
The Estate has existing DFA optic fibre sleeves
Existing Electrical Services:
The proposed site area has electrical pipes running deep within the facility.
Existing Stormwater Services:
Upon Initial Site Assessments as per the Findings and Assessment Reports prior to this report, outlined
that the existing initial stormwater infrastructures seem to only be the below shown culvert which is
the outlet structures in both Plots 20 and 29 and as shown below are in good condition.
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FIGURE 3 -EXISTING CULVERT
6.4 Environmental Requirements
The Project under study shall require an Environmental Management Plan for Implementation of the
Design and Construction of Stormwater Drainage in Ruimsig Country Estate. Assessment of the Project
indicate the following Environmental needs:
LEGAL REQUIREMENTS
National Environmental Management Act (Act 107 of 1998)
A brief assessment was made considering the available information of the proposed project and it was
concluded that in terms of National Environmental Management Act, 1998 (Act No. 107 of 1998) (as
amended) (NEMA) and its 2014 regulations (as amended), which were published in April 2017,
Environmental Authorisation will not be required. Considering the available information, it is
concluded that since work will be undertaken in a natural channel, a Water Use Authorisation will be
required.
6.5 Environmental Management Plan (EMP)
The Environmental Management Plan (EMP) will be prepared to assist in ensuring that impacts
affecting the environment are minimized and avoided where necessary during the remedial works for
Implementation of the construction of Storm Water Drainage in Ruimsig, Gauteng.
A draft EMP will be prepared as per Regulation 33 and will include:

Details of the person who prepared the EMP and their expertise;

Information on the proposed management or mitigation measures that will be taken to address
environmental impacts in respect of:
o
Planning and Design;
o
Pre-construction and Construction Activity;
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o
Operation or undertaking of the activity;
o
Rehabilitation of the environment; and Closure

Detailed description of the aspects of the activity that are covered by the EMP;

Identification of the persons who will be responsible for implementation;

Proposed mechanisms for monitoring compliance with and performance assessment against the
EMP and reporting;

As far as is reasonably practicable, measures to rehabilitate the environment affected by the
undertaking of any listed activity to its natural or predetermined state or to a land use which
conforms to the generally accepted principle of sustainable development, including, where
appropriate, concurrent or progressive rehabilitation measures;

Description of the way it is intended to: Modify, remedy, control or stop any action, activity or
process which causes pollution or environmental degradation.
6.6 Way Leave Applications
The Engineer will engage with an investigation on possible wayleaves to be obtained from existing
services owners and distribute notifications accordingly.
6.7 Hydraulic Modelling Analyses
DorDave’s professional engineering services will entail the development of a hydrological model with
viable parameters to model a realistic hydraulic solution. This phase will be approached by using
software such as Civil 3D and Stormwater and Sanitary Analysis (SSA) from Autodesk. The model will be
generated using industry norms and Employer guidelines to ensure a viable setup for a practical
hydraulic model analysis. This model will provide different solutions to be considered to lower flood
risk towards the residences at The Ruimsig Country Estate. A holistic storm water assessment will have
to be conducted in order to establish the condition of the storm water system in the area. This is
essential, as the improvements proposed will have a significant impact on residents and commuters in
Ruimsig.
7. ENGINEERING DESIGN STANDARDS
7.1 Design Philosophy
With cognizance of the site conditions, and the results from the site assessment, the design was based
on long term requirements with an emphasis on Labour Intensive Construction (LIC); yet, the basic
engineering design philosophy will be integrated i.e. Safety, Functionality and Cost.
7.2 Stormwater Design Guidelines
The design and construction of the infrastructure shall generally be in accordance with the publications
listed below. Any specifications will take cognizance of the particular requirements of the project.
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Table 1: Design Guidelines
Guideline
Title
Reference
A
SABS1200: Standardized Specifications for Civil Engineering Constructions
B
Guidelines for the Provision of Engineering Services and amenities in Residential
Township Development: Issued by The National Housing Board
C
The Red Book: Guidelines for Human Settlement Planning and Design Vol.1 & 2
D
UTG 4: Guidelines for Rural Storm-water Management
E
SANRAL Drainage Manual
7.3 Proposed Design Criteria
The detail design will consider the following items into consideration:
Safety Requirements
The Prime design will be based on the safety requirements to protect the workers during the
construction and the community during the life span of the infrastructure. Several control measures
will be used during construction to protect the workers against potential hazards.
Functionality
The infrastructure should be functional and must serve its intended purpose during the lifespan.
Cost
The project cost will be reduced as much as possible without compromising the quality of the final
product.
Environment
All requirements regarding the protection of the environment as stated in the National Environmental
Management Act (NEMA) will be adhered to, as per GDARD requirements.
Private open space 20 and 29 will be assumed to be the discharge points by the outlet structures.
Registration of servitude is required
Bulk Sewer and Reticulation
± 2222222m of 160mm diameter sewer gravity main
7.4 Observed Road Elements
The Mogale Local Municipality cadastrals were obtained in order to ascertain any property
encroachment onto the road reserves. No existing obstructions were observed for construction.
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7.4.1
Horizontal alignment
The horizontal alignment of the road was found to be in accordance with the accepted codes and no
horizontal improvements were proposed.
7.4.2
Vertical alignment
The original road vertical alignment was found to be in accordance with the accepted codes and no
vertical improvements were proposed.
(See Attached Ground Profiles Appendix 2)
7.5 Stormwater Design
7.5.1
General Principles
The provision of storm water management and control is compulsory for the safety and well-being of
the community and whether piped or canalized, the interest, safety and security of the population shall
receive the highest priority. No storm water runoff will be allowed to flow overland from a road onto
private property.
Storm water should be conveyed in streets as far as possible, trapezoidal concrete channels will be
constructed on the low side when the flow volumes for the 5-year storm exceed the capacity of the
streets. The minimum width of these channels is 2.5m. The channels will be allowed to flow full during
the five-year storm. In practice, this means that water will overflow the channel on the lower side, but
only into the road reserve, and not on to the ervens. The sloping nature of the area will allow water
runoff to be conveyed within roads and open channels, the minor and major systems have been
designed to accommodate a 1:5 and 1:50 year design flood respectively. Road drainage will form an
integral component of both the major and minor system.
7.5.2
Design Criteria for Stormwater
The following design guidelines are proposed to be used on the project and listed in Table 2 - Hydrology
below obtained from the guidelines and specifications as per Table 6.1 [Red Book] and Table 3–
Hydraulics
Table 2: Hydrology
Parameter
1
2
Design Flood Frequencies
Element
Recommendation
Minor Systems (Residential)
5 Years
Major Systems (Residential)
50 Years
Stormwater Ponds
50 Years
Sub Catchment
Residential
35% - 48%
Imperviousness
Industrial
40% - 55%
CBD
50% - 62%
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3
4
Open Areas
15% - 25%
Unknown
30% - 35%
Schools
25% - 38%
Manning’s retardance
Surface:
Ranges:
coefficients for overland flow
Bare Clay – Loam Soil
0.012 – 0.033
Sparse vegetation
0.053 – 0.130
Veld
0.100 – 0.200
Lawns
0.170 – 0.480
Minimum Invert slope
1:250 (0.40%) Lined
Maximum Embankment
1:50 (2.00%) Unlined
Slope (Grassed)
1:5 (20%)
Minimum Depth
1.5m
Stormwater Ponds
Table 3: Hydraulics
Parameter
1
Minimum Sizes
Element
Recommendation
Pipes
300 mm
Culverts
600 mm
2
Pipe Culvert Material
Reinforced Concrete
Bearing SANS mark
3
Pipe Classes
Pipes
Generally, 100D
Box Culverts
Generally, 100S
(Loading conditions for each
application to be confirmed)
4
Bedding Type
Pipes
Class B (SANS 1200 LB)
5
Minimum Slope
Connections (450 mm)
1:100 (1%)
Main Lines
1:200 (0,5%)
6
Minimum Velocity
Pipe and Box Culverts
0,7 m/s
7
Maximum Velocity
Pipe and Culverts
5,0 m/s
On Roads
3,0 m/s
8
Minimum Cover
General
900 mm
9
Maximum Distance
300 - 600 mm
100m
between Manholes
700 – 900 mm
125m
1000 1400 mm
130m
1500 mm – and up
300m
Manning Equation
Recommended Ranges
Concrete
n = 0,013 – 0,016 s/m ᶺ(1/3)
Grass blocks
n = 0,025 – 0,035 s/m ᶺ(1/3)
Paving
n = 0,013 – 0,018 s/m ᶺ(1/3)
River bed
n = 0,025 – 0,050 s/m ᶺ(1/3)
Open Stormwater
Minimum Longitudinal Slope
1:200 (0.50%)
Channels
Maximum flow velocity
1 m/s Unlined
Maximum Side Slopes
1:2 – 1:4 (Lined) Depends
10
11
Hydraulic Calculations
on Lining
1:5 (Unlined)
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7.5.3
Stormwater Drainage Design Proposal
The stormwater management of the site aims to prevent flooding and erosion by discharging the
stormwater runoff away from the residential areas in a manner that poses the least danger to
pedestrians and vehicular traffic. In addition, due to the presence of dolomite, the stormwater
drainage is designed to be watertight, such that the stormwater runoff does not infiltrate the natural
ground. Spot Elevation on different sections will indicate as to the direction of the flow and steepness
at each point. Channels assist with runoffs.
7.5.4
Open Drainage Channels
Minor and major stormwater systems were designed for 1:5 and 1:50 year storm return periods
respectively. A pre and post-development stormwater run-off analysis was performed using the
Rational Method Simulation Model. This was used to determine the impact of the development on the
general drainage of the area.
Provision of a minor stormwater system include Open Drainage Channels (Sub-Surface Drainage)
infrastructure that will accommodate 1:5 and 1:50 year recurrence interval upstream and downstream
respectively. The channel design will achieve the following:

A system that is in-line with the guidelines and standards of the Red Book and SANRAL Drainage
Manual,

Effective collection of stormwater run-off with open channels running within the road reserve,

Avoids flooding and damage of property,

Accommodates required minor and major storms efficiently, and

Minimizes erosion and post-development impacts
7.5.5
Design Methodology
The design will be based on Rainfall data from the TR102 Rainfall data. Using the Design Rainfall
Estimation South Africa Software. Ruimsig Country Estate is classified to be under Krugersdorp thus I’ll
Adopt Krugersdorp Weather Station and calibrate a week’s duration for the several return period.
Catchment Areas will be established where the Rational Method will be used for the Catchment
Calculations using Excel Programmed Sheets. The following weather station is proposed to be utilized
in the hydrological process for determining the rainfall within Ruimsig. Ruimsig soil for Catchment
Calculations will be classified according to the SCS Classification. The Kerb Inlets placing and Manholes
were made on the basis of the hydrological data and calculations. Included in the Assessment is the
Long Sections of Several of the Roads in the estate.
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Table 4-Proposed Weather Station
TR102 N-DAY RAINFALL DATA
Weather Service
MEAN ANNUAL PRECIPITATION
KRUGERSDORP
798
Station:
Weather Service
Coordinates
0475456_W
26°6´27°46´
Station No.
2- year return period daily rainfall from
Days Thunder
58.2mm
TR102
DURATION(DAYS)
RETURN PERIODS (YEARS)
2
5
10
20
50
1
53.0
73.2
88.5
104.8
128.5
2
68.2
94.6
115.0
137.1
170.1
3
77.3
106.5
129.0
153.2
189.1
4
83.2
113.5
136.7
161.5
197.9
5
90.0
122.4
146.6
172.2
209.3
6
95.4
129.5
154.8
181.3
219.2
7
100.4
136.0
162.2
189.5
228.3
7.5.6
mm
(°) (´)
(°) (´)
100
148.4
198.3
219.7
228.8
240.2
250.5
260.1
200
170.3
229.9
253.7
263.0
273.9
284.5
294.4
Catchment Calculations
Krugersdorp is within the Johannesburg region which when checking the exact Soil Type as per the
above diagram is Soil Type B. tc will be taken as 15mins.
Longest Path goes from Upstream to Downstream. Methodology used:
Water Path depends on the Contours. Logically From a highpoint to a low point.
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Catchment Results:
Catchment A
3
Peak Discharge (m /s) for the
Return Periods
5yr
20yr
50yr
100yr
1 Status Quo Scenario
0.20
0.30
0.40
0.49
Catchment B
3
Peak Discharge (m /s) for the
Return Periods
5yr
20yr
50yr
100yr
1 Status Quo Scenario
0.17
0.27
0.35
0.43
Catchment C
3
Peak Discharge (m /s) for the
Return Periods
5yr
20yr
50yr
100yr
1 Status Quo Scenario
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0.26
0.39
0.51
0.63
7.6 CURRENT EXISTING WATER COLLECTION SYSTEM CAPACITY:
Table 4 below sets out design parameters used in calculating the current existing water collection
systems which were used to determine the sizes of the pipes as well as designing their longitudinal
sections. So as to determine the current collection systems capacity as they have 15% stormwater
infiltration.
Table 5: Water System Design Parameters
Description
Average demand (per dwelling house)
Minimum cover to pipes in midblock
Minimum cover to pipes in road verge
Minimum cover to pipes in under road
Minimum gradient
(160mm dia.)
(200mm dia.)
(250mm dia.)
Minimum gradient at the head of the line
Value
1000 l/d
600mm
1400mm
1400mm
1:220
1:300
1:400
1:100
Design key factors:

For Stormwater 600mmØ Class 100D Precast Concrete Pipes

All manholes to be 1m Ø concrete rings

Maximum spacing of 100m to accommodate certain local authority concerned that has only hand
operated rodding equipment.

Pipelines will be positioned within the 2m property servitudes i.e. 1m off on either side of the
boundary.

Heavy duty concrete manhole covers to be used in mid-block and road reserves while cast iron
covers will be used where manholes are within roadway.

Excavation will depend on the soil profiles determined in the geotechnical report/information
available confirming the nature of existing ground.
Table 6: ADF PER SINGLE FAMILY DWELLING UNIT
Income group
Liters per dwelling
unit per day
Based on average
total person per
dwelling
Lower
500
Middle
750
Higher
1000
7
6
5
Ruimsig Country Estate (Higher income group)
Number of dwelling Units = 298 for 1000𝐥
20 | P a g e
1. AVERAGE DAILY FLOW
𝐀𝐃𝐅 = 𝟏𝟎𝟎𝟎 × 𝟐𝟗𝟖
= 𝟐𝟗𝟖 𝟎𝟎𝟎 𝐥/𝐝𝐚𝐲
=
𝟐𝟗𝟖 𝟎𝟎𝟎
𝟖𝟔𝟒𝟎𝟎
= 𝟑. 𝟒𝟓 𝐥/𝐬
2. PEAK DAILY FLOW
𝐏𝐃𝐅 = 𝐏𝐟 (𝐀𝐃𝐅)
Average total person per dwelling = 5
𝐏𝐟 =
=
𝟏𝟖 + √𝐏
𝐏 =
𝟔 + √𝐏
𝟓 × 𝟐𝟗𝟖
𝟏𝟒𝟗𝟎
=
= 𝟏. 𝟒𝟗
𝟏𝟎𝟎𝟎
𝟏𝟎𝟎𝟎
𝟏𝟖 + √𝟏. 𝟒𝟗
𝟔 + √𝟏. 𝟒𝟗
= 𝟐. 𝟔𝟔
∴ 𝐏𝐃𝐅 = 𝟐. 𝟔𝟔 𝐱 𝟑. 𝟒𝟓
𝐏𝐃𝐅 = 𝟗. 𝟏𝟖 𝐥/𝐬
𝐀𝐝𝐝𝐢𝐧𝐠 𝟏𝟓 % 𝐭𝐨 𝐚𝐥𝐥𝐨𝐰 𝐟𝐨𝐫 𝐬𝐭𝐨𝐫𝐦𝐰𝐚𝐭𝐞𝐫 𝐢𝐧𝐟𝐢𝐥𝐭𝐫𝐚𝐭𝐢𝐨𝐧
𝐏𝐖𝐅 = 𝟗. 𝟏𝟖 𝐱 (𝟏. 𝟏𝟓) = 𝟏𝟎. 𝟓𝟔 𝐥/𝐬
3. DIAMETER AND MINIMUM GRADIENT OF PIPE
𝝅
𝑸
(𝒅)² =
𝟒
𝒗
𝑸 = 𝑨𝒗
𝑸 = 𝑷𝑾𝑭 𝒂𝒏𝒅 𝑽 = 𝒎𝒊𝒏𝒊𝒎𝒖𝒎 𝒗𝒆𝒍𝒐𝒄𝒊𝒕𝒚 𝒐𝒇 𝟎. 𝟕 𝒎/𝒔
𝟒 𝟎. 𝟎𝟏𝟎𝟓𝟔 𝟎.𝟓
𝒅² = [
]
𝝅
𝟎. 𝟕
= 𝟎. 𝟏𝟑𝟗𝒎
𝟒. 𝑭𝒍𝒐𝒘 𝒑𝒆𝒓 𝒄𝒂𝒕𝒄𝒉𝒎𝒆𝒏𝒕 𝒂𝒓𝒆𝒂 (𝑨, 𝑩 𝒂𝒏𝒅 𝑪)
𝑻𝒐𝒕𝒂𝒍 𝑨𝑫𝑭 = 𝟑. 𝟒𝟓 𝒍/𝒔
𝑷𝒆𝒓 𝒔𝒕𝒂𝒏𝒅 = 𝟑. 𝟒𝟓/𝟐𝟗𝟖 = 𝟎. 𝟎𝟏𝟐 𝒍/𝒔
𝑻𝒐𝒕𝒂𝒍 𝑷𝑫𝑭 = 𝟏𝟎. 𝟓𝟔 𝒍/𝒔
𝑷𝒆𝒓 𝒔𝒕𝒂𝒏𝒅 = 𝟏𝟎. 𝟓𝟔/𝟐𝟗𝟖 = 𝟎. 𝟎𝟑𝟓 𝒍/𝒔
Description
Ruimsig Country Estate
No of stands
298
ADWF (l/s)
3.58
PDWF (l/s)
10.43
Thus this is the current water structures capacity intake
21 | P a g e
DISCUSSIONS
The planning of the stormwater drainage system is based on the following principles:

The prevention of loss of life and significant damage to property resulting from run-off from rare
storms.

The protection of private property from frequent storms

The Provision of convenience to the Community when functioning

Discovering solutions to run-off problem due to Urban Development

Provision of the most economical control facilities compatible with the environment

Protection of water resource from pollution’
The Key issues were determining the appropriate pipe diameter, rainfall analysis of the area, slopes and
cost estimates.The chosen design will accommodate at least a 50 year life span for major systems with
a regulated monthly maintenance programme. The Catchment Layout accounts 5 year for minor
systems and 50year for major systems.
It has been assumed that the capacity of existing road structure in the estate and existing water supply
system will be able to accommodate the new stormwater system development. The proposed
implementation plan is urgently required to avoid further cost implications and is critical that all
planning be conducted during the rainy season. Further deterioration in the drainage structures is
expected hence review of the final design will be important before appointing the contractor.
The constant flow of traffic (public transport and residential vehicle movement) will affect the
workability on site as well as the safety of the workers. It will be necessary to temporarily divert traffic
in stages according to the different sections of the roads under study, especially along the main access
routes. This will be challenging as traffic during peak hour will affect progress on site.
The disposal of surplus material (existing servitude material and asphalt) will be challenging since a
disposal spot could not be identified in the site vicinity. The hauling of the material to a distant disposal
spot will increase the construction cost of the project.
Where the new pipes intersect, or go along existing services like water pipelines, sewer pipelines, fibre
optics etc Wayleave applications will need to be made to the appropriate authorities for wayleave
agreements.
Plot 20 and 29 have existing Culverts Existing Kerbs are completely dilapidated but pavement is in good
shape. New Salberg Semi-Mountable Kerb and Channel will be installed. Detail Designs using Civil 3D
and SSA will be presented to the Client upon Approval of The Preliminary Designs.
22 | P a g e
RECOMMENDATIONS
The chosen stormwater system won’t require any silt traps as the Estate being upmarket is unlikely to
have oil or waste clogging the kerb inlets or pipes. The Stormwater pipes have been selected upon
reasoning that need be a full human being can access the structure for inspection or maintenance and
thus the reasoning behind the 600mmØ CLASS 100D Ogee Jointed Precast Concrete Pipes. The pipes
will discharge at Plot No. 20 and 29, where there’s an existing Culvert in which the water flows to a
nearby Attenuation Pond. The flow path followed should be as per the Engineers recommendation,
which is from a high point to a low point. This new system should tie-into the existing sewer
infrastructure. It is recommended that the capacity of existing infrastructure is checked before
construction of the new system commences so that if any upgrades are required, they are done
concurrently with the new stormwater system, so that their costs are factored in the client’s budget.
Instead of V-drains or Surface Concrete Channels, adopt Stormwater escapes by the side openings of
street humps or ramps preferably. Channels can be considered for Private Properties owned by
Residents.
Minimal damage on Street Furniture and Residential Property needs to be adhered to. The existing
water and sewer systems depth need to be checked before the commencement of any excavations. It
is assumed that there is no need to include Culverts in the initial design as there is existing culverts on
private open spaces 20 and 29 that are still in good shape and will be outlet structures. I recommend
that Geotechnical Tests and Surveys to be performed again prior to construction in order to verify the
Preliminary Data received.
CONCLUSION
The Engineer herewith submits this Preliminary Design Report for the Employer’s favourable
consideration as part of the deliverable requirements for Stage 2 – Preliminary Design, depicted in
ECSA Guidelines.
A total of 4000m of Stormwater Piping is required with a Cost Estimation of R R16 079 281,78 for both
Design and Construction excl of day rates shown in Appendix 7.
In order to proceed to Stage 3- Detail Design upon which The Project will go into the tendering stage
for contractor. The final construction drawings will be issued upon Approval of the next phase Detailed
Design Development where all the details, layouts, pipe longsections etc will be issued to the client.
We trust that you find this report in order and remain available to coordinate any enquiries that you
may have in this instance.
23 | P a g e
REFERENCES
 CSIR Building and construction technology, 2005, Guideline for human settlement planning and
design Guideline for human settlement planning and design, volume 1
 CSIR Building and construction technology, 2005, Guideline for human settlement planning and
design Guideline for human settlement planning and design, volume 2
 CSIR Building and construction technology, 2005, Guidelines for Engineering Services and Amenities
in Residential Township Development.
 South African Bureau of Standards 1200, Standards specification for civil engineering construction.
 University of South Africa, 2005, Reticulation design and Management IV, 3rd edition.
24 | P a g e
APPENDICES
25 | P a g e
Appendix 1: Survey Layout
26 | P a g e
NOTES:
GENERAL
1. THIS DRAWING IS TO BE READ IN CONJUNCTION
WITH SABS 1200 STANDARDISED SPECIFICATIONS
AND THE PROJECT SPECIFICATIONS.
2. PRIOR TO THE START OF CONSTRUCTION, ALL
SERVICES WHICH ARE TO BE CROSSED MUST BE
EXPOSED BY HAND TO CONFIRM THEIR POSITIONS
AND LEVELS. ANY DISCREPANCY IS TO BE
IMMEDIATELY REPORTED TO THE ENGINEER.
3. A FULL SET OF MATERIAL TESTS(COMPACTION,
CBR & UCS) REFLECTING COMPLIANCE WITH THE
SPECIFICATIONS IS TO BE SUBMITTED TO THE
ENGINEER FOR ONWARD TRANSMISSION TO THE
EMPLOYER.
4. INTERSECTION SERVICES TO BE EXPOSED,
POSITIONS RECORDED AND ANY CLASHES IN
POSITION WITH THE WORKS TO BE REPORTED TO
THE ENGINEER PRIOR TO THE COMMENCEMENT OF
CONSTRUCTION.
ROADWORKS
1. FULL ROAD RESERVE WIDTH TO BE CLEARED
2. TOPSOIL TO BE REMOVED TO AN AVERAGE DEPTH
OF 150 mm OVER ROAD BOXED CUT
3. 90mm X 190mm DEEP PRECAST CONCRETE
SUNKEN KERBS TO BE USED AS SURFACING EDGE
RESTRAINTS AT ROAD EDGES.
STORMWATER DRAINAGE
Scale 1:1000
1. THE APPLICABLE STANDARDISED SPECIFICATIONS
ARE SABS 1200DB, 1200GA, 1200LB & 1200LE READ
WITH RELEVANT CONTRACT PROJECT
SPECIFICATIONS.
2. PIPES OF DIFFERENT DIAMETERS WITHIN ANY
MANHOLE OR KERB INLET ARE TO BE INSTALLED
SOFFIT TO SOFFIT.
3. INVERT LEVELS GIVEN REFER TO THE LARGEST
PIPE IN THE STRUCTURE, UNLESS OTHERWISE
SPECIFIED.
4. ALL STORMWATER PIPES ARE TO BE CLASS 50D
PRECAST CONCRETE OGEE JOINTED PIPES EXCEPT
100D AT ROAD CROSSINGS UNLESS INDICATED
OTHERWISE .
5. PIPE SIZES: AS SHOWN ON LONGITUDINAL
SECTION.
6. MINIMUM COVER TO ALL PIPES TO BE 600 mm.
7. POSITION OF SUBSOIL DRAINAGE WILL BE
DETERMINED ON SITE.
8. REFER TO STD DRAWINGS FOR S/WATER DRAIN
APPURTENANT WORK DETAILS
9. ALL BRICKS TO BE QUALITY FBSE30 TO SABS
227-1986 WATER ABSORPTION <14% AND
EFFLORESCENCE<.
10. ALL BRICKWORK TO BE IN ENGLISH BOND WITH
JOINTS PROPERLY POINTED.
11. SPIGOT AND SOCKET WITH RUBBER RING TO BE
INSTALLED AT LINKS WHERE V>4m/s
A
2020-08-20
ISSUED FOR APPROVAL
No.
Date
Revision Description
REVISION SCHEDULE
CLIENT
APPROVAL
ENGINEER
PR ENG no.
DATE
CLIENT
DATE
DESIGNED
DRAWN
CHECKED
M MATHIBEDI
M MATHIBEDI
B SONTI
PROJECT
RUIMSIG COUNTRY ESTATE
STORMWATER DRAINAGE
SYSTEMS
DRAWING DESCRIPTION
SURVEY LAYOUT
REV DATE
SCALE
SIZE
2020-08-20
1:1000
A0
DRAWING NUMBER
PROJ No - PHASE - DISCIPLINE - STAGE - DOC - SERV - LEV - No - (SHEET)
REV
P01-1104-UNI-01
0
Appendix 2: DTM Model & Ground Profile
27 | P a g e
NOTES:
GENERAL
1. THIS DRAWING IS TO BE READ IN CONJUNCTION
WITH SABS 1200 STANDARDISED SPECIFICATIONS
AND THE PROJECT SPECIFICATIONS.
2. PRIOR TO THE START OF CONSTRUCTION, ALL
SERVICES WHICH ARE TO BE CROSSED MUST BE
EXPOSED BY HAND TO CONFIRM THEIR POSITIONS
AND LEVELS. ANY DISCREPANCY IS TO BE
IMMEDIATELY REPORTED TO THE ENGINEER.
3. A FULL SET OF MATERIAL TESTS(COMPACTION,
CBR & UCS) REFLECTING COMPLIANCE WITH THE
SPECIFICATIONS IS TO BE SUBMITTED TO THE
ENGINEER FOR ONWARD TRANSMISSION TO THE
EMPLOYER.
4. INTERSECTION SERVICES TO BE EXPOSED,
POSITIONS RECORDED AND ANY CLASHES IN
POSITION WITH THE WORKS TO BE REPORTED TO
THE ENGINEER PRIOR TO THE COMMENCEMENT OF
CONSTRUCTION.
ROADWORKS
1. FULL ROAD RESERVE WIDTH TO BE CLEARED
2. TOPSOIL TO BE REMOVED TO AN AVERAGE DEPTH
OF 150 mm OVER ROAD BOXED CUT
3. 90mm X 190mm DEEP PRECAST CONCRETE
SUNKEN KERBS TO BE USED AS SURFACING EDGE
RESTRAINTS AT ROAD EDGES.
STORMWATER DRAINAGE
1. THE APPLICABLE STANDARDISED SPECIFICATIONS
ARE SABS 1200DB, 1200GA, 1200LB & 1200LE READ
WITH RELEVANT CONTRACT PROJECT
SPECIFICATIONS.
2. PIPES OF DIFFERENT DIAMETERS WITHIN ANY
MANHOLE OR KERB INLET ARE TO BE INSTALLED
SOFFIT TO SOFFIT.
3. INVERT LEVELS GIVEN REFER TO THE LARGEST
PIPE IN THE STRUCTURE, UNLESS OTHERWISE
SPECIFIED.
4. ALL STORMWATER PIPES ARE TO BE CLASS 50D
PRECAST CONCRETE OGEE JOINTED PIPES EXCEPT
100D AT ROAD CROSSINGS UNLESS INDICATED
OTHERWISE .
5. PIPE SIZES: AS SHOWN ON LONGITUDINAL
SECTION.
6. MINIMUM COVER TO ALL PIPES TO BE 600 mm.
7. POSITION OF SUBSOIL DRAINAGE WILL BE
DETERMINED ON SITE.
8. REFER TO STD DRAWINGS FOR S/WATER DRAIN
APPURTENANT WORK DETAILS
9. ALL BRICKS TO BE QUALITY FBSE30 TO SABS
227-1986 WATER ABSORPTION <14% AND
EFFLORESCENCE<.
10. ALL BRICKWORK TO BE IN ENGLISH BOND WITH
JOINTS PROPERLY POINTED.
11. SPIGOT AND SOCKET WITH RUBBER RING TO BE
INSTALLED AT LINKS WHERE V>4m/s
Scale 1:1000
A
2020-08-20
ISSUED FOR APPROVAL
No.
Date
Revision Description
REVISION SCHEDULE
CLIENT
APPROVAL
ENGINEER
PR ENG no.
DATE
CLIENT
DATE
DESIGNED
DRAWN
CHECKED
M MATHIBEDI
M MATHIBEDI
B SONTI
PROJECT
RUIMSIG COUNTRY ESTATE
STORMWATER DRAINAGE
SYSTEMS
DRAWING DESCRIPTION
DTM LAYOUT
TRIANGLE|POINTS|CONTOURS
1m and 5m
REV DATE
SCALE
SIZE
2020-08-20
1:1000
A0
DRAWING NUMBER
PROJ No - PHASE - DISCIPLINE - STAGE - DOC - SERV - LEV - No - (SHEET)
REV
P01-1104-UNI-02
0
NOTES:
GENERAL
1. THIS DRAWING IS TO BE READ IN CONJUNCTION
WITH SABS 1200 STANDARDISED SPECIFICATIONS
AND THE PROJECT SPECIFICATIONS.
2. PRIOR TO THE START OF CONSTRUCTION, ALL
SERVICES WHICH ARE TO BE CROSSED MUST BE
EXPOSED BY HAND TO CONFIRM THEIR POSITIONS
AND LEVELS. ANY DISCREPANCY IS TO BE
IMMEDIATELY REPORTED TO THE ENGINEER.
3. A FULL SET OF MATERIAL TESTS(COMPACTION,
CBR & UCS) REFLECTING COMPLIANCE WITH THE
SPECIFICATIONS IS TO BE SUBMITTED TO THE
ENGINEER FOR ONWARD TRANSMISSION TO THE
EMPLOYER.
4. INTERSECTION SERVICES TO BE EXPOSED,
POSITIONS RECORDED AND ANY CLASHES IN
POSITION WITH THE WORKS TO BE REPORTED TO
THE ENGINEER PRIOR TO THE COMMENCEMENT OF
CONSTRUCTION.
ROADWORKS
1. FULL ROAD RESERVE WIDTH TO BE CLEARED
2. TOPSOIL TO BE REMOVED TO AN AVERAGE DEPTH
OF 150 mm OVER ROAD BOXED CUT
3. 90mm X 190mm DEEP PRECAST CONCRETE
SUNKEN KERBS TO BE USED AS SURFACING EDGE
RESTRAINTS AT ROAD EDGES.
STORMWATER DRAINAGE
1. THE APPLICABLE STANDARDISED SPECIFICATIONS
ARE SABS 1200DB, 1200GA, 1200LB & 1200LE READ
WITH RELEVANT CONTRACT PROJECT
SPECIFICATIONS.
2. PIPES OF DIFFERENT DIAMETERS WITHIN ANY
MANHOLE OR KERB INLET ARE TO BE INSTALLED
SOFFIT TO SOFFIT.
3. INVERT LEVELS GIVEN REFER TO THE LARGEST
PIPE IN THE STRUCTURE, UNLESS OTHERWISE
SPECIFIED.
4. ALL STORMWATER PIPES ARE TO BE CLASS 50D
PRECAST CONCRETE OGEE JOINTED PIPES EXCEPT
100D AT ROAD CROSSINGS UNLESS INDICATED
OTHERWISE .
5. PIPE SIZES: AS SHOWN ON LONGITUDINAL
SECTION.
6. MINIMUM COVER TO ALL PIPES TO BE 600 mm.
7. POSITION OF SUBSOIL DRAINAGE WILL BE
DETERMINED ON SITE.
8. REFER TO STD DRAWINGS FOR S/WATER DRAIN
APPURTENANT WORK DETAILS
9. ALL BRICKS TO BE QUALITY FBSE30 TO SABS
227-1986 WATER ABSORPTION <14% AND
EFFLORESCENCE<.
10. ALL BRICKWORK TO BE IN ENGLISH BOND WITH
JOINTS PROPERLY POINTED.
11. SPIGOT AND SOCKET WITH RUBBER RING TO BE
INSTALLED AT LINKS WHERE V>4m/s
A
2020-08-20
ISSUED FOR APPROVAL
No.
Date
Revision Description
REVISION SCHEDULE
CLIENT
APPROVAL
ENGINEER
PR ENG no.
DATE
CLIENT
DATE
DESIGNED
DRAWN
CHECKED
M MATHIBEDI
M MATHIBEDI
B SONTI
PROJECT
RUIMSIG COUNTRY ESTATE
STORMWATER DRAINAGE
SYSTEMS
DRAWING DESCRIPTION
GROUND PROFILES
REV DATE
SCALE
SIZE
2020-08-20
1:1000
A0
DRAWING NUMBER
PROJ No - PHASE - DISCIPLINE - STAGE - DOC - SERV - LEV - No - (SHEET)
REV
P01-1104-UNI-05
0
Appendix 3: Stormwater Layout
28 | P a g e
NOTES:
GENERAL
1. THIS DRAWING IS TO BE READ IN CONJUNCTION
WITH SABS 1200 STANDARDISED SPECIFICATIONS
AND THE PROJECT SPECIFICATIONS.
2. PRIOR TO THE START OF CONSTRUCTION, ALL
SERVICES WHICH ARE TO BE CROSSED MUST BE
EXPOSED BY HAND TO CONFIRM THEIR POSITIONS
AND LEVELS. ANY DISCREPANCY IS TO BE
IMMEDIATELY REPORTED TO THE ENGINEER.
3. A FULL SET OF MATERIAL TESTS(COMPACTION,
CBR & UCS) REFLECTING COMPLIANCE WITH THE
SPECIFICATIONS IS TO BE SUBMITTED TO THE
ENGINEER FOR ONWARD TRANSMISSION TO THE
EMPLOYER.
4. INTERSECTION SERVICES TO BE EXPOSED,
POSITIONS RECORDED AND ANY CLASHES IN
POSITION WITH THE WORKS TO BE REPORTED TO
THE ENGINEER PRIOR TO THE COMMENCEMENT OF
CONSTRUCTION.
PAVED AREA
ROADWORKS
1. FULL ROAD RESERVE WIDTH TO BE CLEARED
2. TOPSOIL TO BE REMOVED TO AN AVERAGE DEPTH
OF 150 mm OVER ROAD BOXED CUT
3. 90mm X 190mm DEEP PRECAST CONCRETE
SUNKEN KERBS TO BE USED AS SURFACING EDGE
RESTRAINTS AT ROAD EDGES.
-1
KI
OSIRIS AVENUE
PAVED AREA
PAVED AREA
PAVED AREA
-5
KI
-3
KI
STORMWATER DRAINAGE
KI-13
PAVED AREA
W
NE
NEW
600mm
W
NE
mØ
0m
60
Ø S/W
PIPES
VALHALLA STREE
T
ES
PIP
S/W STREET
UNICOR
MH-20
PIP
-6
KI
LILLI
PUT
MH-13
KI
-11
KI-9 M
H14
K
MH
-17
-8
H
M
24 -25
H
MH
-23 M
LO
REA
KI-15
MH
EET
T STR
CAME
ES
P
PI
PAVED A
-14
I
K
MH-26
MH
-16
KI-16
MH-28
MH-27
KI
-17
PAVED A
KI-19
NE
W
REA
N
CAME
LO
UTOPIA STRAAT
KI
-1
0
60
0
T STR mm
EET
Ø
MH-29
AREA
KI-23
5
-2
KI-24
00mm
PAVED AR
EA
PAVED AREA
A
2020-08-20
ISSUED FOR APPROVAL
No.
Date
Revision Description
REVISION SCHEDULE
NEW 6
MH-37
-18
PARAD
KI
PIPES
MH-38
YVONNE STRAAT
AREA
PAVED
YVETTE STRAAT
MH-39
PI
YS TUR
N
PAVED
15
NEW 6
00mm
Ø
KI-21
S/
W
MH
-
KI
S/W P
KI-22
PAVED AREA
PE
S
IPES
IA
UTOP
KI-20
T
STRAA
ANUBIS STRAAT
-2
-5
MH
EW
-18
-19
REET
-4
KI
KI
-4
H
M
7
KI-
MH
VALHA
LLA ST
ES
-3
MH
-6 S/W
H
M mØ
0m
0
6
MH
Ø S/W
PIPES
VALHALLA STREE
T
I-8
M
MH
MH-10
600mm
Ø S/W
S/W
Scale 1:1000
7
H-
-2
MH
MH-12
NEW
-9
MH
MH-22
TURN
PH
ES
PIP
ET
S/W OENIX STRE
PAVED AR
MH-11
-1
Outlet
Structure
MH
-21
EA
N
mØ
mØ
0m
60
E
W IRIS AVENU
NE
OS
0m
60
KI-12
1. THE APPLICABLE STANDARDISED SPECIFICATIONS
ARE SABS 1200DB, 1200GA, 1200LB & 1200LE READ
WITH RELEVANT CONTRACT PROJECT
SPECIFICATIONS.
2. PIPES OF DIFFERENT DIAMETERS WITHIN ANY
MANHOLE OR KERB INLET ARE TO BE INSTALLED
SOFFIT TO SOFFIT.
3. INVERT LEVELS GIVEN REFER TO THE LARGEST
PIPE IN THE STRUCTURE, UNLESS OTHERWISE
SPECIFIED.
4. ALL STORMWATER PIPES ARE TO BE CLASS 100D
PRECAST CONCRETE OGEE JOINTED PIPES UNLESS
INDICATED OTHERWISE .
5. PIPE SIZES: 600mm DIA.
6. MINIMUM COVER TO ALL PIPES TO BE 600 mm.
7. POSITION OF SUBSOIL DRAINAGE WILL BE
DETERMINED ON SITE.
8. REFER TO STD DRAWINGS FOR S/WATER DRAIN
APPURTENANT WORK DETAILS
9. ALL BRICKS TO BE QUALITY FBSE30 TO SABS
227-1986 WATER ABSORPTION <14% AND
EFFLORESCENCE<.
10. ALL BRICKWORK TO BE IN ENGLISH BOND WITH
JOINTS PROPERLY POINTED.
11. SPIGOT AND SOCKET WITH RUBBER RING TO BE
INSTALLED AT LINKS WHERE V>4m/s
CLIENT
PAVED AR
EA
m
RAAT
AV ST
GUST
6 m
-2 600
W
KI
NE
MH-36
Ø
W
S/
P
PI
KI-28
ES
MH-30
KI-27
APPROVAL
MH-35
ENGINEER
MH-34
PR ENG no.
DATE
KI-29
KI
-3
0
MH-32
CLIENT
DATE
MH-31
MH-33
Outlet
Structure
DESIGNED
DRAWN
CHECKED
M MATHIBEDI
M MATHIBEDI
B SONTI
PROJECT
RUIMSIG COUNTRY ESTATE
STORMWATER DRAINAGE
SYSTEMS
DRAWING DESCRIPTION
STORMWATER LAYOUT
REV DATE
SCALE
SIZE
2020-08-20
1:1000
A0
DRAWING NUMBER
PROJ No - PHASE - DISCIPLINE - STAGE - DOC - SERV - LEV - No - (SHEET)
REV
P01-1104-UNI-03
0
Appendix 4: Catchment Layout
29 | P a g e
NOTES:
GENERAL
PAVED AREA
Critical Path B
PAVED AREA
ROADWORKS
1. FULL ROAD RESERVE WIDTH TO BE CLEARED
2. TOPSOIL TO BE REMOVED TO AN AVERAGE DEPTH
OF 150 mm OVER ROAD BOXED CUT
3. 90mm X 190mm DEEP PRECAST CONCRETE
SUNKEN KERBS TO BE USED AS SURFACING EDGE
RESTRAINTS AT ROAD EDGES.
PAVED AREA
-5
KI
mØ
0m
60
N
PH
ES
PIP
ET
S/W OENIX STRE
ES
PIP
S/W STREET
mØ
PIP
-6
KI
ES
7
H-
-4
KI
-2
-1
MH
-2
MH
-3
MH
-4
H
M
7
KI-5
MH
EW
-6 S/W
H
M mØ
0m
0
6
MH-12
MH-10
I-8
K
-8
H
M
LO
REA
KI-15
MH
EET
T STR
CAME
ES
P
PI
PAVED A
24 -25
H
MH
-23 M
M
KI
-14
I
K
MH-26
KI-19
KI-16
MH
-18
REA
CAME
LO
KI-20
-11
MH
-17
KI
-1
0
60
0
T STR mm
EET
Ø
MH-29
IPES
00mm
ANUBIS STRAAT
5
-2
PAVED AR
EA
PI
KI
-18
PAVED AREA
PARAD
KI
MH-37
15
YS TUR
N
YVONNE STRAAT
KI-23
PIPES
MH-38
YVETTE STRAAT
AREA
PAVED
Ø S/W
MH-39
AREA
S/
W
MH
-
PE
S
S/W P
Catchment Area C
Area = 1.556ha
Longest Path =785.357m
Us Lvl =1501.30m
l =1478.36m
Ds
KI-2Lv
4
Q5yr =0.26m³/s
Q50yr =0.51m³/s
PAVED AREA
NEW 6
00mm
Ø
KI-21
PAVED
-19
KI
KI
UTOPIA STRAAT
KI-22
MH
MH-28
NE
W
T
STRAA
MH-22
-16
MH-27
N
IA
UTOP
PAVED AR
-17
PAVED A
Outlet
Structure
MH
-21
EA
MH
A
2020-08-20
ISSUED FOR APPROVAL
No.
Date
Revision Description
REVISION SCHEDULE
NEW 6
Scale 1:1000
KI-12
Catchment Area B
MH-20
Area = 1.021ha
Longest Path=588.984m
10.45m
15
=
l
Lv
Us
NEW
600mm
Ø S/WDs Lvl = 1495.31m
PIPES
VALHALLA STREE
T
MH-13
I-9 M/s
Q5yr =0.17Km3
H14
Q50yr =0.35m³/s
UNICOR
0m
60
S/W
-9
MH
Ø S/W
PIPES
VALHALLA STREE
T
REET
W
NE
mØ
0m
60
E
W IRIS AVENU
NE
OS
MH-11
600mm
1. THE APPLICABLE STANDARDISED SPECIFICATIONS
ARE SABS 1200DB, 1200GA, 1200LB & 1200LE READ
WITH RELEVANT CONTRACT PROJECT
SPECIFICATIONS.
2. PIPES OF DIFFERENT DIAMETERS WITHIN ANY
MANHOLE OR KERB INLET ARE TO BE INSTALLED
SOFFIT TO SOFFIT.
3. INVERT LEVELS GIVEN REFER TO THE LARGEST
PIPE IN THE STRUCTURE, UNLESS OTHERWISE
SPECIFIED.
4. ALL STORMWATER PIPES ARE TO BE CLASS 100D
PRECAST CONCRETE OGEE JOINTED PIPES UNLESS
INDICATED OTHERWISE .
5. PIPE SIZES: 600mm DIA
6. MINIMUM COVER TO ALL PIPES TO BE 600 mm.
7. POSITION OF SUBSOIL DRAINAGE WILL BE
DETERMINED ON SITE.
8. REFER TO STD DRAWINGS FOR S/WATER DRAIN
APPURTENANT WORK DETAILS
9. ALL BRICKS TO BE QUALITY FBSE30 TO SABS
227-1986 WATER ABSORPTION <14% AND
EFFLORESCENCE<.
10. ALL BRICKWORK TO BE IN ENGLISH BOND WITH
JOINTS PROPERLY POINTED.
11. SPIGOT AND SOCKET WITH RUBBER RING TO BE
INSTALLED AT LINKS WHERE V>4m/s
VALHA
LLA ST
W
NE
NEW
TURN
-3
KI
PAVED AREA
Catchment Area A
Area = 1.244ha
Longest Path =803.297m
Us Lvl = 1524.02m
Ds Lvl = 1500.65m
Q5yr = 0.20m³/s
Q50yr = 0.40 m³/s
STORMWATER DRAINAGE
KI-13
LILLI
PUT
-1
KI
OSIRIS AVENUE
PAVED AREA
Critical Path A
1. THIS DRAWING IS TO BE READ IN CONJUNCTION
WITH SABS 1200 STANDARDISED SPECIFICATIONS
AND THE PROJECT SPECIFICATIONS.
2. PRIOR TO THE START OF CONSTRUCTION, ALL
SERVICES WHICH ARE TO BE CROSSED MUST BE
EXPOSED BY HAND TO CONFIRM THEIR POSITIONS
AND LEVELS. ANY DISCREPANCY IS TO BE
IMMEDIATELY REPORTED TO THE ENGINEER.
3. A FULL SET OF MATERIAL TESTS(COMPACTION,
CBR & UCS) REFLECTING COMPLIANCE WITH THE
SPECIFICATIONS IS TO BE SUBMITTED TO THE
ENGINEER FOR ONWARD TRANSMISSION TO THE
EMPLOYER.
4. INTERSECTION SERVICES TO BE EXPOSED,
POSITIONS RECORDED AND ANY CLASHES IN
POSITION WITH THE WORKS TO BE REPORTED TO
THE ENGINEER PRIOR TO THE COMMENCEMENT OF
CONSTRUCTION.
CLIENT
PAVED AR
EA
m
RAAT
AV ST
GUST
6 m
-2 600
W
KI
NE
Ø
W
S/
KI-28
P
PI
Critical Path C
MH-36
ES
MH-30
KI-27
APPROVAL
MH-35
ENGINEER
MH-34
PR ENG no.
DATE
KI-29
KI
-3
0
MH-32
CLIENT
DATE
MH-31
MH-33
Outlet
Structure
DESIGNED
DRAWN
CHECKED
M MATHIBEDI
M MATHIBEDI
B SONTI
PROJECT
RUIMSIG COUNTRY ESTATE
STORMWATER DRAINAGE
SYSTEMS
DRAWING DESCRIPTION
CATCHMENT LAYOUT
REV DATE
SCALE
SIZE
2020-08-20
1:1000
A0
DRAWING NUMBER
PROJ No - PHASE - DISCIPLINE - STAGE - DOC - SERV - LEV - No - (SHEET)
REV
P01-1104-UNI-04
0
Appendix 5: Design Calculations
30 | P a g e
ARCUS GIBB
Peak Discharge Calculation using SCS UH and Rational Method
SCS CN Calculation:
1. It is assumed that the standard Durban Metro Landuse categories have been converted to one of the
ten GIBB-MLST categories listed in the "Landuse Look-up Table" sheet.
2. It is also assumed that the standard soil types (e.g. Cartref, Clovelly) abstracted from the soil map
theme in GIS have been converted to one of the seven categories in the "Soil Types" sheet.
3. In the GIS, the landuse and soil type themes need to be clipped to the boundaries of each subcatchment (previously determined using HEC-GeoHMS).
4. Using GIS, for each sub-catchment determine the areas of different soil types that fall under each of
the different landuse categories. This will determine the average weighted SCS Curve Number for that
particular sub-catchment - see example below. (In theory, because there are 10 different landuse
categories, and 7 soil types, a sub-catchment could have a Curve Number which is the weighted average
of 70 Curve Numbers. In reality, this is not likely, because not all landuses would occur in a small subcatchment.) The subcatchment landuse/soil type areas are entered in the "SCS CN & Rational C
Calculation" sheet
5. There is an error check which determines whether the total area of all the soil type/landuse
combinations within each sub-catchment is equal to the actual sub-catchment total.
JAM/JA0522A-7120
Rational_Cmt Area C : Methodology
1 of 3
2020/09/16
ARCUS GIBB
SCS lag Calculation:
1. Catchment physical parameters are entered in the "Q Calc" sheet. The parameters can be obtained
manually from catchment maps or abstracted from the DEM in the GIS.
2. The parameters are used to calcuate both SCS lag time and in the Rational Method.
3. The lag time and CN are then used with the synthetic SCS unit hydrograph to determine peak
discharge (this can be calculated readily using the SCS program from Univ Natal or in HEC-HMS for
interlinked basins).
Rational Method Calculation:
1. The Rational Method runoff coefficient, Ct = Ft(aC1) + bC2
where a = % of catchment that is rural
b = % of catchment that is urban
C 1 = Cy + Cp + Cv
where Cy = vlei's and pans
0%
flat areas
3%
hilly areas
10%
C2 =
Mean Average Rainfall (mm)
599
600
900
0,01
0,03
0,05
0,06
0,08
0,11
0,12
0,16
0,2
0,22
steep areas
30%
0,26
0,3
Cp = very permeable
0,03
A
0,04
0,05
permeable
0,06
B
0,08
0,1
semi-permeable
0,12
C
0,16
0,2
impermeable
0,21
D
0,26
0,3
Cv = thick bush & plantations Natural Forest 0,03
/ Thick Bush 0,04
0,05
light bush & farmland
Natural Forest 0,07
/ Light Bush /0,11
Farmland
0,15
grass-lands
0,17
Grasslands - Veld
0,21
0,25
no vegetation
0,26
None
0,28
0,3
SUM(%typei x Ci)
where Lawns/Parks (Heavy Soil)
0,30
0,30
0,30
0,70
0,50
0,30
0,80
0,75
0,95
Residential - Flats
Residential - Small Plots
Residential - Large Plots
City Centre
Industry
Streets
Ft =
0,70
0,50
0,30
0,80
0,75
0,95
0,70
0,50
0,30
0,80
0,75
0,95
0,50 for 2yr return period
0,55 for 5yr return period
0,60 for 10yr return period
0,67 for 20yr return period
0,83 for 50yr return period
1,00 for 100yr return period
2. Peak discharge Qt = 0.278*Ct* It* A
JAM/JA0522A-7120
Rational_Cmt Area C : Methodology
where Ct is defined above
It is described by the IDF relationship
A is area in km2
2 of 3
2020/09/16
ARCUS GIBB
IDF Relationship (SA Co-axial diagram, Midgley & Pitman, 1978))
DWAF :
Inland
Coastal
JAM/JA0522A-7120
Rational_Cmt Area C : Methodology
I = [( 7.5 + 0.034 MAP ) R 0.3] / [( 0.24 + td ) 0.89)
I = [( 3.4 + 0.023 MAP ) R 0.3] / [( 0.20 + td ) 0.75)
3 of 3
2020/09/16
Design Peak Flood Estimation using Rational Method
Enter data in blue text areas
Catchment Ref. Post-Dev_Cmt A
Location Ruimsig Country Estate
WR Catchment
Krugersdorp
MAP
798 mm
2
Catchment Area
0,01224 km
Longest Flow Path
803,297 m
H 0.85 elevation
1524,02 m MSL
H 0.10 elevation
1500,65 m MSL
Time of Entry
15 minutes
Land Use / Soils combinations (% of catchment area)
A
A/B
B
Grasslands - Veld
0%
Natural Forest / Light Bush / Farmland
Natural Forest / Thick Bush
Open Spaces (50-75% grass cover)
Residential - 500m2 lot size (65% impervious)
80%
Residential - 1000m2 lot size (38% impervious)
Residential - 2000m2 lot size (25% impervious)
Commercial/business areas (85% impervious)
Industrial Districts (72% impervious)
Paved areas
20%
3
Rational Design Peak Discharges (m /s)
Q2y =
Q5y =
Q10y =
Q20y =
Q50y =
Q100y =
Rational_Cmt Area A : Data Entry
3
0,15 m /s
3
0,20 m /s
B/C
C
C/D
D
SCS CN = 88
SCS Lag (min) = 16,0
Ia (mm) = 0.2S = 7
3
0,25 m /s
3
0,30 m /s
3
0,40 m /s
3
0,49 m /s
2020/09/15
Design Peak Flood Estimation using Rational Method
Enter data in blue text areas
Catchment Ref. Post-Dev_Cmt B
Location Ruimsig Country Estate
WR Catchment
Krugersdorp
MAP
798 mm
2
Catchment Area
0,01021 km
Longest Flow Path
588,984 m
H 0.85 elevation
1510,45 m MSL
H 0.10 elevation
1495,31 m MSL
Time of Entry
15 minutes
Land Use / Soils combinations (% of catchment area)
A
A/B
B
Grasslands - Veld
0%
Natural Forest / Light Bush / Farmland
Natural Forest / Thick Bush
Open Spaces (50-75% grass cover)
Residential - 500m2 lot size (65% impervious)
80%
Residential - 1000m2 lot size (38% impervious)
Residential - 2000m2 lot size (25% impervious)
Commercial/business areas (85% impervious)
Industrial Districts (72% impervious)
Paved areas
20%
Rational Design Peak Discharges (m 3 /s)
Q2y =
Q5y =
Q10y =
Q20y =
Q50y =
Q100y =
Rational_Cmt Area B : Data Entry
3
0,13 m /s
3
0,17 m /s
B/C
C
C/D
D
SCS CN = 88
SCS Lag (min) = 14,8
Ia (mm) = 0.2S = 7
3
0,22 m /s
3
0,27 m /s
3
0,35 m /s
3
0,43 m /s
2020/09/16
Design Peak Flood Estimation using Rational Method
Enter data in blue text areas
Catchment Ref. Post-Dev_Cmt C
Location Ruimsig Country Estate
WR Catchment
Krugersdorp
MAP
798 mm
2
Catchment Area
0,01556 km
Longest Flow Path
588,984 m
H 0.85 elevation
1501,30 m MSL
H 0.10 elevation
1495,31 m MSL
Time of Entry
15 minutes
Land Use / Soils combinations (% of catchment area)
A
A/B
B
Grasslands - Veld
0%
Natural Forest / Light Bush / Farmland
Natural Forest / Thick Bush
Open Spaces (50-75% grass cover)
Residential - 500m2 lot size (65% impervious)
80%
Residential - 1000m2 lot size (38% impervious)
Residential - 2000m2 lot size (25% impervious)
Commercial/business areas (85% impervious)
Industrial Districts (72% impervious)
Paved areas
20%
Rational Design Peak Discharges (m 3 /s)
Q2y =
Q5y =
Q10y =
Q20y =
Q50y =
Q100y =
Rational_Cmt Area C : Data Entry
3
0,19 m /s
3
0,24 m /s
B/C
C
C/D
D
SCS CN = 88
SCS Lag (min) = 17,3
Ia (mm) = 0.2S = 7
3
0,30 m /s
3
0,37 m /s
3
0,49 m /s
3
0,60 m /s
2020/09/16
Appendix 6: Schedule of Preliminary Quantities based on the Preliminary Design in accordance with
Standardized Specification SABS 1200.
31 | P a g e
Appendix 7: Cost Estimate
32 | P a g e
RUIMSIG COUNTRY ESTATE
CONTRACT NO: CJ5502
SCHEDULE A : STORMWATER ENGINEERING DESIGN
ITEM
NO
DESCRIPTION
SECTION 1000
UNIT
QUANTITY
RATE
AMOUNT
A10.00
Engineering Services
A10.03
Structural Engineer_ Stormwater Design
Hrs.
45
963,13
43 340,85
A10.04
Geotechnical Engineer_ Geotechnical Investigation
Sum
1
72 280,00
72 280,00
A10.05
Land Suverory_Topographical Survey Verification
Sum
1
21 500,00
21 500,00
A10.06
Liaison with Local Municipality
Sum
18
963,13
17 336,34
A10.00
TOTAL CARRIED TO SUMMARY
154 457,19
RUIMSIG COUNTRY ESTATE STORMWATER DRAINAGE
CONTRACT NO: CJ5502
PRELIMINARY COST ESTIMATE
SCHEDULE A : STORMWATER ENGINEERING DESIGN
ITEM
NO
SECTION 1200
DESCRIPTION
UNIT
QUANTITY
RATE
AMOUNT
(i) soft material
m³
400
R65,00
R26 000,00
(ii) hard material
m³
0
R350,00
R0,00
GENERAL PROVISIONS AND REQUIREMENTS
1 Excavation for Services
Excavating material within the following depth
ranges below ground level for the exposing of/or
searching for services
(a)
1200
0m to 2m
Carried forward
R26 000,00
SCHEDULE B : STORMWATER CONSTRUCTION
ITEM
NO
SECTION 1200
DESCRIPTION
UNIT
QUANTITY
RATE
Brought forward
AMOUNT
26 000,00
2 Backfilling
Backfilling
(a)
Using the excavated material
m³
250
65,00
16 250,00
(b)
Using imported selected material
m³
395
260,00
102 700,00
Provisional sum for existing services to be
relocated and/or protected as ordered by the
engineer
-
Sum
R 15 000
Handling costs and profit in respect of
sub-item B12.03(a)
%
5%
750,00
3 Existing services
(a)
(b)
R 15 000,00
4 Community Liaison Officer
(a)
Provisional sum for the payment of the
Community Liaison Officer
-
Sum
R 9 000
Provisional sum for the payment of PSC
Members cost for attendance of meetings
-
Sum
R 3 500
Handling costs and profit in respect of
sub-item B12.04(a)
%
R 12 500,00
5%
625,00
Initial obligations i.r.o OSHAC
sum
1
12000,00
12 000,00
(b)
Submission of OSHAC File
sum
1
500,00
500,00
(c)
Time realated obligations for OSHAC
Weeks
4
1200,00
4 800,00
(b)
(c)
5 (a)
1200
TOTAL CARRIED TO SUMMARY
SCHEDULE B : STORMWATER CONSTRUCTION
191 125,00
SECTION 1300
ITEM
NO
DESCRIPTION
UNIT
QUANTITY
RATE
AMOUNT
-
lump
sum
95 000,00
CONTRACTOR'S ESTABLISHMENT ON SITE
AND GENERAL OBLIGATIONS
6 The Contractor's general obligations:
(a)
Fixed obligations
(b)
Value-related obligations
-
lump
sum
0,00
(c)
Time-related obligations
Weeks
4
18 000,00
72 000,00
NB
The combined total tendered for subitems
(a), (b) and (c) shall not exceed 15% of the
Tender Sum, excluding VAT.
TOTAL CARRIED TO SUMMARY
SCHEDULE B : STORMWATER CONSTRUCTION
ITEM
NO
167 000,00
SECTION 1500
DESCRIPTION
UNIT
QUANTITY
RATE
AMOUNT
man-day
90
150,00
13 500,00
ACCOMMODATION OF TRAFFIC
7 Temporary traffic-control facilities:
1500
(a)
Flagmen
(h)
Delineators 800 mm x 200 mm sides:
(i)
Single
number
2
380,00
760,00
(ii)
Mounted back to back
number
4
165,00
660,00
(i)
Movable barricade/road sign combination
number
4
750,00
3 000,00
(j)
Traffic cones, 750 mm high
number
15
105,00
1 575,00
(n)
Provision of high visibility safety jackets
and safety hats
number
15
350,00
5 250,00
Carried forward
24 745,00
SCHEDULE B : STORMWATER CONSTRUCTION
ITEM
NO
SECTION 1500
DESCRIPTION
UNIT
QUANTITY
RATE
AMOUNT
Brought forward
24 745,00
8 Watering of temporary deviations
kilolitre
75
12,50
937,50
m
2
1 050,00
2 100,00
Blading by road grader of:
9 Temporary culverts:
(a)
Provision and laying of temporary
prefabricated culverts complete:
Type SC 75 D-load pipes with ogee joints on class B bedding:
(1) 600 mm dia
1500
Carried forward
27 782,50
SCHEDULE B : STORMWATER CONSTRUCTION
ITEM
NO
SECTION 1500
DESCRIPTION
UNIT
QUANTITY
RATE
AMOUNT
Brought forward
27 782,50
OVERHAUL
(Section 1600)
10 Overhaul on material hauled in excess of a
free-haul distance of 0,5 km, for haul up to
or through 1,0 km (restricted overhaul)
m³
675
5,00
3 375,00
m³
675
45,00
30 375,00
CLEARING AND GRUBBING
(Section 1700)
BORROW MATERIALS
(Section 3100)
11 Excess overburden
1500
TOTAL CARRIED TO SUMMARY
58 157,50
SCHEDULE B : STORMWATER CONSTRUCTION
ITEM
NO
SECTION 1800
DESCRIPTION
UNIT
QUANTITY
RATE
AMOUNT
h
h
h
22,5
27,5
97,33
Rate only
Rate only
Rate only
h
33,5
Rate only
h
h
980
995
Rate only
Rate only
15 Loader (0.5m³)
h
980
Rate only
16 Grader (CAT 140G or similar)
h
1350
Rate only
17 LDV
h
1450
Rate only
h
h
h
695
885
950
Rate only
Rate only
Rate only
19 Hand Controlled Compactors
(i)
Pedestrian roller (Bomag BW90)
(ii)
Vibratoy plate
(iii)
Rammers
h
h
h
750
750
980
Rate only
Rate only
Rate only
20 Water truck (min 10 000 l)
h
950
Rate only
21 Dozer (D7 or similar)
h
1450
Rate only
DAYWORKS ITEMS
12 Laourers:
(i)
(ii)
(iii)
Unskilled
Semi-skilled
Skilled
13 Foreman
14 Tipper trucks
(i)
(ii)
3-5 ton
5.1 - 10 ton
18 Compaction Roller:
(i)
(ii)
(iii)
1800
Vibrator roller
Tamping roller
Grid roller
TOTAL CARRIED TO SUMMARY
2300
22
23
24
2300
0,00
Kerbing
Kerbing on perimeter sides of the road
Semi Mountable Kerbs
Salberg Kerb Inlets
m
number
number
1 500
500
30
120,00
185,00
232,00
180 000,00
92 500,00
6 960,00
279 460,00
SCHEDULE B : STORMWATER CONSTRUCTION
ITEM
NO
SECTION 3100
DESCRIPTION
UNIT
QUANTITY
m³
675,00
RATE
AMOUNT
BORROW MATERIALS
25 Excess overburden
(a)
3100
Depth up to and including 0.5m
50,00
TOTAL CARRIED TO SUMMARY
33 750,00
SCHEDULE B : STORMWATER CONSTRUCTION
ITEM
NO
33 750,00
SECTION 3500
DESCRIPTION
UNIT
QUANTITY
RATE
AMOUNT
STABILIZATION
26 Chemical stabilization extra over unstabilized
compacted layers:
(c)
Gravel subbase, 150 mm thick
m³
675
33,50
22 612,50
(d)
Gravel base, 150 mm thick
m³
675
33,50
22 612,50
t
12,5
1 900,00
23 750,00
27 Chemical stabilizing agent:
(a)
3500
Ordinary Portland cement
CEM II/B-M(V-S) 32.5N or similar approved
TOTAL CARRIED TO SUMMARY
68 975,00
SCHEDULE B : STORMATER CONSTRUCTION
SECTION 4100
SCHEDULE B : STORMWATER CONSTRUCTION
ITEM
NO
SECTION 4200
DESCRIPTION
UNIT
QUANTITY
RATE
AMOUNT
m2
3000,00
145,00
435 000,00
ASPHALT BASE AND SURFACING
28 Backfilling of excavations for patching with:
(a)
Asphalt surfacings continuously medium-penetration grade bitumen
graded asphalt, 30 mm thickness using 60/70
penetration grade bitumen
4200
TOTAL CARRIED TO SUMMARY
435 000,00
SCHEDULE B : STORWATER CONSTRUCTION
SECTION 5600
ITEM
NO
DESCRIPTION
UNIT
QUANTITY
RATE
AMOUNT
m
no
4000,00
39
2800,00
555,00
11 200 000,00
21 645,00
CONCRETE PIPES AND MANHOLES
29 CLASS 100 D 600mm dia Precast Concrete Pipes
30 1m Concrete Ring Manholes
5600
TOTAL CARRIED TO SUMMARY
11 221 645,00
SCHEDULE B : STORMWATER CONSTRUCTION
SECTION 5700
SCHEDULE B : STORMWATER CONSTRUCTION
SECTION 8100
ITEM
NO
DESCRIPTION
UNIT
QUANTITY
RATE
AMOUNT
TESTING MATERIALS AND WORKMANSHIP
31
(a)
Site Laboratory for Engineer:
(i)
Rental of equipment
Sum
1,00
78500,00
78500,00
(ii)
Charge on Prime Cost Sum
%
R 78 500
5%
3925,00
PC Sum
1,00
18000,00
18000,00
%
R 18 000
5%
900,00
32 (b)
8100
Other special tests requested by the Engineer:
(i)
Cost of testing
(ii)
Charge on Prime Cost Sum
TOTAL CARRIED TO SUMMARY
101 325,00
RUIMSIG COUNTRY ESTATE
CONTRACT NO: LNM012/2020/21
SCHEDULE A : STORMWATER ENGINEERING DESIGN
SUMMARY OF SCHEDULES OF QUANTITIES
SCHEDULE A: STORMWATER ENGINEERING SERVICES
1000
Stormwater Engineering Design
R154 457,19
TOTAL SCHEDULE A: ENGINEERING SERVICES
R154 457,19
SCHEDULE B: STORMWATER CONSTRUCTION
1200
General requirements and provisions
R191 125,00
1300
Contractor's establishment on site and general obligations
R167 000,00
1500
Accommodation of traffic
R58 157,50
1800
Dayworks
2300
Concrete kerbing, concrete channeling, open concrete chute and linings
R279 460,00
3100
Borrow materials
R33 750,00
3500
Stabilization
R68 975,00
4200
Asphalt base and surfacing
R435 000,00
5600
Concrete Pipes and Manholes
R11 221 645,00
8100
Testing the materials and workmanship
R101 325,00
TOTAL SCHEDULE B: STORMWATER CONSTRUCTION
R12 556 437,50
TOTAL DESIGN & CONSTRUCTION
R12 710 894,69
R0,00
Contigency 10%
R1 271 089,47
Sub Total
R13 981 984,16
Tax 15%
R2 097 297,62
Total Offer
R16 079 281,78