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     T HE UNITED R EPUBLIC OF  T  ANZANIA MINISTRY  OF  W ORKS 

    Standard

    Specification

    for

    oad Works

    Standard

    Specification

    for

    oad Works

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     T HE UNITED R EPUBLIC OF  T  ANZANIA 

    MINISTRY  OF  W ORKS 

    Standard

    Specification

    for

    oad Works

    Standard

    Specification

    for

    oad Works

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    STANDARD SPECIFICATIONS FOR ROAD WORKS-2000

    THE UNITED REPUBLIC OF TANZANIA, MINISTRY OF WORKS

    Reproduction of extracts from this document maybe made subject to due acknowledgement of thesource.

    Although this document is believed to be correct atthe time of printing, the Ministry of Works does notaccept any contractual, tortious or other form ofliability for its content or for any consequencesarising from its use. People using the informationcontained in the document should apply and relyon their own skill and judgement to the particularissue that they are considering

    Printed by: Novum Grafisk AS, Skjetten, Norway

    Layout: Rolf Johansen, ViaNova and Jan Edvardsen, ICG, Norway

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    STANDARD SPECIFICATIONS FOR ROAD WORKS-2000

    THE UNITED REPUBLIC OF TANZANIA, MINISTRY OF WORKS

    This Standard Specifications for Road Works - 2000 has been prepared as acomponent under the Institutional Cooperation between the Ministry of Works (MoW),Central Materials Laboratory (CML) and the Norwegian Public Roads Administration(NPRA). The Government of Tanzania and the Norwegian Agency for InternationalDevelopment (NORAD) have jointly financed the project, which forms part of a

    programme to establish technical standards, guidelines and specifications for road andhighway engineering.

    This document has been prepared by a Working Group under the supervision of aSteering Committee comprising the following members from the Ministry of Works:

    Mr. JL Ngumbulu Director of Trunk Roads ()

    Mr. JW Kijazi Director of Rural Roads

    Mr. DJ Mariki Ag. Chief Engineer, CML

    Mr. LJ Mujjungi Ag. Chief Engineer, Design and Construction, Trunk Roads

    Mr. GJ Kinyero Ag. Chief Engineer, Design and Construction, Rural Roads

    The Working Group consisted of the following members:

    Mr. AS Idabaga MoWMr. ST Rwegumisa MoW

    Mr. C Overby NPRA

    Mr. R Johansen ViaNova ()

    The Steering Committee and the Working Group wish to acknowledge the significantcontribution from all people giving critical comments and advice during the preparationof this document. In particular, the comprehensive input from contributors within theMinistry of Works and the private sector who commented on the draft, is gratefullyacknowledged.

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    STANDARD SPECIFICATIONS FOR ROAD WORKS-2000

    THE UNITED REPUBLIC OF TANZANIA, MINISTRY OF WORKS  

    Acknowledgements

    Table of Contents

    Crossection Terminology

    Series 1000 General

    Series 2000 Drainage

    Series 3000 Earthworks and Pavement Layers of Gravel or Crushed Stone

    Series 4000 Bituminous Layers and Seals

    Series 5000 Ancillary Roadworks

    Series 6000 Structures

    Series 7000 Tolerances, Testing and Quality Control

    Appendices:Appendix 1 Summary of Pay ItemsAppendix 2 List of Clauses Referring to the Special Specifications or Drawings

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    STANDARD SPECIFICATIONS FOR ROAD WORKS-2000

    THE UNITED REPUBLIC OF TANZANIA, MINISTRY OF WORKS  

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    STANDARD SPECIFICATIONS FOR ROAD WORKS-2000 SERIES 1000 - GENERAL

    THE UNITED REPUBLIC OF T ANZANIA, MINISTRY OF WORKS P AGE 1000 - 1

    SERIES 1000

    General

    SECTION P AGE

    1100 DEFINITIONS AND TERMS 1000-21200 GENERAL REQUIREMENTS ANDPROVISIONS 1000-6

    1300 CONTRACTOR’S ESTABLISHMENT ONSITE AND GENERAL OBLIGATIONS 1000-20

    1400 ENGINEER’S ACCOMMODATION AND ATTENDANCE UPON ENGINEER ANDHIS SITE PERSONNEL 1000-22

    1500 ACCOMMODATION OF TRAFFIC 1000-301600 OVERHAUL 1000-341700 ENVIRONMENTAL PROTECTION AND

    W ASTE DISPOSAL 1000-35

    CONTENTS OF THE STANDARD SPECIFICATIONS FOR ROAD WORKS 2000:

     ACKNOWLEDGEMENTSCROSSECTION TERMINOLOGY

    SERIES 1000GENERALSERIES 2000 DRAINAGESERIES 3000 E ARTHWORKS AND P AVEMENT L AYERS OF GRAVEL OR CRUSHED STONESERIES 4000 BITUMINOUS L AYERS AND SEALSSERIES 5000 ANCILLARY ROADWORKSSERIES 6000 STRUCTURES

    SERIES 7000 TOLERANCES, TESTING AND QUALITY CONTROL

     APPENDICES

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    STANDARD SPECIFICATIONS FOR ROAD WORKS-2000 SERIES 1000 - GENERAL

    THE UNITED REPUBLIC OF T ANZANIA, MINISTRY OF WORKS P AGE 1000 - 2

    SERIES 1000: GENERAL

    SECTION 1100: DEFINITIONS AND TERMS

    CONTENTS:

    CLAUSE P AGE

    1101 ACCEPTED 1000-21102 ACCESS CULVERT 1000-21103 AGGREGATE 1000-21104 APPROVED 1000-21105 ASPHALT CONCRETE SURFACING 1000-21106 B ASE COURSE 1000-21107 BITUMINOUS MIX 1000-21108 BITUMINOUS SEAL 1000-21109 BORROW AREA 1000-21110 BORROW PIT 1000-21111 BORROW M ATERIAL 1000-21112 BRIDGE 1000-21113 C ARRIAGEWAY 1000-31114 C ATCHWATER DRAIN OR B ANK 1000-31115 CERTIFICATE OF GUARANTEE 1000-31116 COMMON EXCAVATION 1000-31117 CONDITIONS OF CONTRACT 1000-31118 CROSSFILL 1000-31119 CULVERT 1000-31120 CUT 1000-31121 DIRECTED 1000-31122 E ARTHWORKS 1000-31123 E ARTHWORKS M ATERIAL TYPES 1000-31124 EMBANKMENT 1000-31125 FILL 1000-31126 FORMATION LEVEL 1000-31127 GRADE LINE 1000-31128 GRADING MODULUS (GM) 1000-31129 IMPROVED SUBGRADE 1000-31130 INLET AND OUTLET DRAINS 1000-31131 L ANE 1000-31132 LOT 1000-31133 MEDIAN 1000-31134 MEDIAN DRAIN 1000-31135 MITRE DRAIN AND B ANK 1000-31136 OVERBURDEN 1000-31137 P AVEMENT 1000-31138 P AVEMENT M ATERIAL CLASSES 1000-31139 PIONEER L AYER 1000-41140 PRESPLITTING 1000-41141 ROADBED 1000-41142 ROAD PRISM 1000-41143 ROAD RESERVE OR RIGHT-OF-W AY 1000-41144 ROCK EXCAVATION 1000-41145 ROLLER P ASSES 1000-41146 SERVICES 1000-41147 SHOULDER 1000-4

    1148 SHOULDER BREAKPOINT 1000-41149 SIDE DRAIN 1000-41150 SIDEFILL 1000-41151 SLOPE 1000-51152 SPECIFICATIONS 1000-51153 SPOIL (M ATERIAL) 1000-51154 STABILISATION 1000-51155 SUBBASE 1000-51156 SUBGRADE, IMPROVED 1000-51157 SUBSOIL DRAINAGE SYSTEM 1000-51158 SUBSIDIARY WORKS 1000-51159 SUBSTRUCTURE 1000-51160 SUITABLE M ATERIALS 1000-51161 TOPSOIL 1000-51162 TRAVELLED W AY 1000-51163 UNSUITABLE M ATERIALS 1000-5

    1164 VERGE 1000-51165 WORKING DRAWINGS 1000-51166 QUARRY 1000-5

    Unless inconsistent with the context, in theseSpecifications, the following terms, words or expressions shall have the meanings hereby assignedto them. CROSSECTION TERMINOLOGY, page V, refers for details on the cross-sectional elements of the road.

    1101 ACCEPTED Accepted in writing by the Engineer (or by the Employer 

    where appropriate) as meeting the requirements of theContract Documents and of any authorised variationsthereto. “Acceptance” means accepted in writing asaforesaid. “Acceptable” means acceptable to theEngineer as aforesaid.

    1102 ACCESS CULVERT An access culvert provides an opening under anintersecting side road or entrance to plots along theproject road.

    1103 AGGREGATECrushed stone of specified size and quality to be usedin the Works.

    1104 APPROVED

     Approved in writing by the Engineer, includingsubsequent written approval or confirmation of previousverbal approval by the Engineer. “Approval” meansapproval in writing as aforesaid.

    1105 ASPHALT CONCRETE SURFACINGThe layer - or layers - of a bituminous mix constructedon top of the base course made of a mixture topredetermined proportions of aggregate, filler andbituminous binder material prepared in a mixing plant tomeet the requirements for surfacing material class AC20, AC14 or AC10 and placed by means of a pavingmachine.

    1106 BASE COURSE A layer of material constructed on top of the subbase or in the absence thereof, the improved subgrade layer. Abase course may extend to outside the carriageway.

    1107 BITUMINOUS MIX A mixture of a bituminous binder and aggregate, butexcluding penetration macadam.

    1108 BITUMINOUS SEAL A bituminous surfacing made by the application of oneor more layers of bituminous binder with layers of aggregate in successive layers.

    1109 BORROW AREA An area within designated boundaries, approved for thepurpose of obtaining borrow materials.

    1110 BORROW PITThe excavated pit in a borrow area.

    1111 BORROW MATERIAL Any gravel, sand, soil, stones or ash obtained fromborrow areas, dumps or sources other than cut withinthe road prism and which is used in the construction of the Works. It shall not include crushed stone or sandobtained from commercial sources and blasted rock for crushing.

    1112 BRIDGE A structure for carrying motor, railways, pedestrian or other traffic or services over a river, watercourse,

    railway line or any other gap, with a single span length,or sum of span lengths, of 2.0 metres or more. Thelength is measured between the abutment faces, or pier head faces respectively, along the centre line of theroad at girder-bed level.

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    STANDARD SPECIFICATIONS FOR ROAD WORKS-2000 SERIES 1000 - GENERAL

    THE UNITED REPUBLIC OF T ANZANIA, MINISTRY OF WORKS P AGE 1000 - 3

    1113 CARRIAGEWAYThe surface normally traversed by vehicles and whichconsists of one or a number of contiguous traffic lanes,include auxiliary lanes and shoulders.

    1114 CATCHWATER DRAIN OR BANK A longitudinal drain or bank outside the road prism for diverting water that should otherwise flow into the road

    prism.

    1115 CERTIFICATE OF GUARANTEE A signed statement by a person having legal authorityto bind a company or supplier to its product, and whichconfirms that the materials and test results conform tothe standards of the Specifications.

    1116 COMMON EXCAVATIONClassification of excavation for payment purposes.Denotes all excavation, except rock excavation,required from the road prism, drains, etc. according tothe Drawings and the Specifications.

    1117 CONDITIONS OF CONTRACTThe appropriate edition of the General Conditions of Contract issued for execution of the Contract together with any Special or Particular Conditions of Contractforming part of the Contract.

    1118 CROSSFILLCrossfill is earthworks materials taken from cuts in theroad reserve and placed in embankments at a distanceof 50m or less from its original position, measured alongthe centreline of the road.

    1119 CULVERT A structure other than a bridge, which provides anopening under the carriageway or median for drainageor other purposes.

    1120 CUT A section of the road where the formation level is belowthe original ground level requiring excavations for theconstruction of the pavement layers.

    1121 DIRECTEDDirection in writing by the Engineer including verbaldirection when subsequently confirmed in writing.

    1122 EARTHWORKSTerm describing all processed material below theformation level including improved subgrade layers, filland prepared roadbed.

    1123 EARTHWORKS MATERIAL CLASSESMaterials used in earthworks, complying with the

    requirements of the Specifications, classified as follows:

    G15 natural gravel/soils with nominal CBR valueof minimum 15

    G7 natural gravel/soils with nominal CBR valueof minimum 7

    G3 natural gravel/soils with nominal CBR valueof minimum 3

    DR Dump rock, un-graded waste rock

    1124 EMBANKMENT A section of the road where the formation level is abovethe original ground level.

    1125 FILLThat portion of the road prism consisting of approved

    imported material which lies above the roadbed and isbounded by the side slopes, on which the improvedsubgrade layers, subbase, base course, shoulders andare to be constructed. Material imported to replaceunsuitable material in the roadbed shall also be

    classified as fill when placed below the improvedsubgrade layers.

    1126 FORMATION LEVELThe level of the top of the final layer of earthworks uponwhich the pavement layers are placed.

    1127 GRADE LINE

    The grade line is a reference line in the Drawings of thelongitudinal sections of the road indicating at regular intervals the elevations according to which the road is tobe constructed. The grade line may refer to the level of the completed road, base or any other layer and mayindicate the elevations either along the carriage waycentre line or along any designated position on the roadcross-section.

    1128 GRADING MODULUS (GM)The cumulative percentages by mass of material in arepresentative sample of aggregate, gravel or soilretained on the 2 mm, 0.425 mm and 0.075 mm sieves,divided by 100.

    1129 IMPROVED SUBGRADE

    The upper layer or layers of the earthworks, which isconstructed directly onto the fill or in some cases ontothe roadbed.

    1130 INLET AND OUTLET DRAINSChannels leading into or discharging from culvertsstorm water conduits and minor bridges.

    1131 LANEPart of a travelled way intended for a single stream of traffic in one direction, which has normally beendemarcated as such by road markings.

    1132 LOT A sizeable portion of work or quantity of material which

    is assessed as a unit for the purpose of quality controland selected to represent material or work produced byessentially the same process and materials.

    1133 MEDIANThe area between the two travelled ways of a dualcarriageway, excluding the inner shoulders.

    1134 MEDIAN DRAIN A longitudinal drain situated between the inner shoulders of a dual carriageway.

    1135 MITRE DRAIN AND BANK A drain constructed at an angle to the centreline of theroad to divert water from a side drain. Mitre drainsinclude mitre banks placed across the side drains.

    1136 OVERBURDENMaterial within a borrow area, which is not required or isunsuitable for use in construction.

    1137 PAVEMENTThe upper layers of the road comprising the improvedsubgrade, subbase, base or gravel wearing course or bituminous surfacing and the shoulder layers.

    1138 PAVEMENT MATERIAL CLASSESMaterials used in the pavement, complying with therequirements of the Specifications, classified as follows:

    Unbound natural gravel materials:

    G80: natural gravel with nominal CBR value of minimum 80

    G60: natural gravel with nominal CBR value of minimum 60

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    STANDARD SPECIFICATIONS FOR ROAD WORKS-2000 SERIES 1000 - GENERAL

    THE UNITED REPUBLIC OF T ANZANIA, MINISTRY OF WORKS P AGE 1000 - 4

    G45: natural gravel with nominal CBR value of minimum 45

    G25: natural gravel with nominal CBR value of minimum 25

    GW: gravel wearing course for gravel roads or unpaved shoulders

    Unbound crushed aggregate for base course:CRR: crushed aggregate made from fresh,

    quarried rock compacted to a percentage of the apparent density of the rock, withenhanced requirements for workmanshipduring construction

    CRS: crushed aggregate made from stones,boulders, oversize from borrow pits or quarried rock, compacted to a percentageof the maximum dry density of the materialat BS-Heavy compaction

    Cemented materials for base course or subbase:C2: material with a nominal unconfined

    compression strength of minimum 2 MPacemented by stabilisation with an approvedchemical stabiliser 

    C1: material with a nominal unconfined

    compression strength of minimum 1 MPacemented by stabilisation with an approvedchemical stabiliser 

    CM: material with a nominal unconfinedcompression strength of minimum 0.5 MPamodified by stabilisation with an approvedchemical stabiliser 

    Bituminous mixes for base course:DBM40: hot mixed material of bitumen and

    aggregate having a maximum particlesize of 40 mm

    DBM30: hot mixed material of bitumen andaggregate having a maximum particlesize of 30 mm

    LAMBS: hot mixed material of bitumen and

    aggregate have large particle size asprescribed in the Specifications

    BEMIX: cold mixed material of bitumen emulsionand aggregate

    FBMIX: cold mixed material of foamed bitumenand aggregate

    Penetration macadam for base course:PM80: penetration macadam where the main

    fraction of the aggregate has largestparticle size of a 80 mm

    PM60: penetration macadam where the mainfraction of the aggregate has largestparticle size of a 60 mm

    PM30: penetration macadam where the mainfraction of the aggregate has largest

    particle size of a 30 mm

    Bituminous surfacing: AC20: hot mixed asphalt concrete material of 

    bitumen and aggregate having a maximumparticle size of 20 mm

     AC14: hot mixed asphalt concrete material of bitumen and aggregate having a maximumparticle size of 14 mm

     AC10: hot mixed asphalt concrete material of bitumen and aggregate having a maximumparticle size of 10 mm

    Surface dressing: bituminous seal made withapproved chipping of near similar particlesize, placed in a single layer or in twolayers as specified

    Otta Seal: bituminous seal made withapproved graded aggregate, placed in asingle layer or in two layers as specified

    Sand seal: bituminous seal made withapproved sand for aggregate, placed in asingle layer or in two layers as specified

    Slurry seal: bituminous layer made withapproved crusher dust for aggregate, mixedwith bitumen emulsion and water to form amixture poured into the surface as specified

    1139 PIONEER LAYER An initial layer constructed over a weak roadbed whereselected material is used to provide a stable platform for the construction of subsequent layers.

    1140 PRESPLITTINGEstablishment of a free surface, or shear plane, in rockcuts, by controlled use of explosives in specially alignedand closely spaced drill holes along the slope line.

    1141 ROADBEDThe natural in situ material on which the fill, or in their absence, any pavement layers, are to be constructed.

    1142 ROAD PRISMThat portion of the road construction included between

    the original ground level and the outer boundaries of theslopes of cuttings, fills and side drains. It shall notinclude the selected layer, subbase, base course,surfacing, shoulders or roadbed.

    1143 ROAD RESERVE OR RIGHT-OF-WAYThe entire area included by the boundaries of road asproclaimed.

    1144 ROCK EXCAVATIONClassification of excavation for payment purposes.Denotes excavation required from the road prism,drains, etc. according to the Drawings and theSpecifications, that requires drilling and blasting or theuse of pneumatic or hydraulic jackhammers in order tobe loosened sufficiently for loading and transportation.

    1145 ROLLER PASSESUnless otherwise specified in the Specifications, anarea will be taken to have received one roller passwhen a roller has passed over such area once. Additional passes made only as a result of nominaloverlapping so as to ensure full coverage shall not betaken into account.

    1146 SERVICESCables, pipes or other structures, such as conduits for electricity, telephone and telegraph connections, water,sewage, etc.

    1147 SHOULDER

    (a) When referring to this as a surface: The areabetween the outside edge of the travelled way andthe shoulder break point.

    (b) When referring to this as a pavement layer: Theupper pavement layer lying between the outsideedge of the base course and the shoulder breakpoint.

    1148 SHOULDER BREAKPOINTThe line along which the extended flat planes of thesurface of the shoulder and the outside slope of the filland pavement intersect.

    1149 SIDE DRAIN An open longitudinal drain situated adjacent to and atthe bottom of cut or fill slopes.

    1150 SIDEFILLThat portion of the imported material which lies outsidethe compacted fills, shoulders, base course andsubbase and is contained within such surface slopes as

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    STANDARD SPECIFICATIONS FOR ROAD WORKS-2000 SERIES 1000 - GENERAL

    THE UNITED REPUBLIC OF T ANZANIA, MINISTRY OF WORKS P AGE 1000 - 5

    shown on the Drawings as side fill or as directed by theEngineer.

    1151 SLOPEUnless otherwise stated, slope is given in terms of theratio of the vertical difference in elevation between anytwo points and the horizontal distance between them.This ratio may also be expressed as a percentage.

    1152 SPECIFICATIONSThe Specifications relating to a specific project, whichform part of the Contract documents for such project,and which contain the Standard Specifications together with supplementary and/or amending specificationsissued in the Special Specifications.

    1153 SPOIL (MATERIAL)Material originating from construction operations andwhich is not utilised for construction purposes.

    1154 STABILISATIONThe treatment of the materials used in the constructionof the roadbed, earthworks or pavement layers by theaddition of a cementitious binder such as lime or 

    Portland cement. Asphalt mixes and concrete shall notbe considered as materials that have been stabilised.

    1155 SUBBASEThe layer of material on top of the improved subgradelayers or fill and below the base course and shoulders.

    1156 SUBGRADE, IMPROVEDThe layer of material on top of the roadbed, or fill, andbelow the subbase.

    1157 SUBSIDIARY WORKSWorks which are subsidiary to or necessary or essentialto, or in support of, or usual to, the execution andcompletion of other Works.

    1158 SUBSTRUCTURE All of that part of the structure below the bearings of simple and continuous span bridges, below skewbacksof arches, below deck slab of box and slab culverts,together with return walls and wingwalls.

    1159 SUBSOIL DRAINAGE SYSTEM A system of subsoil drainage pipes (including anypermeable material) constructed to intercept andremove subsoil water.

    1160 SUITABLE MATERIALMaterials that comply with the requirements of theseSpecifications in respect of the relevant layer or positionwhere the material is intended to be used.

    1161 TOPSOILOrganic or unsuitable materials in the upper strataencountered after clearing of the vegetation.

    1162 TRAVELLED WAYThat portion of the carriageway, which includes thevarious traffic lanes and auxiliary lanes but excludes theshoulders.

    1163 UNSUITABLE MATERIALMaterials that do not comply with all the requirements of these Specifications in respect of the relevant layer or position where the material is intended to be used.

    1164 VERGEThe area between the outer edge of the road prism andthe boundary of the road reserve.

    1165 WORKING DRAWINGSShop drawings, steel bending schedules, stress sheets,fabrication and erection drawings, falsework drawings,and any other supplementary drawings or data whichthe Contractor is required to submit to the Engineer for approval before such Works commence.

    1166 QUARRY

     Area other than cuts within the road prism where rock isextracted for production of crushed aggregate andwhich is used in the construction of the Works.

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    STANDARD SPECIFICATIONS FOR ROAD WORKS-2000 SERIES 1000 - GENERAL

    THE UNITED REPUBLIC OF T ANZANIA, MINISTRY OF WORKS P AGE 1000 - 6

    SERIES 1000: GENERAL

    SECTION 1200: GENERALREQUIREMENTS ANDPROVISIONS

    CONTENTS:

    CLAUSE P AGE

    1201 SCOPE 1000-61202 SERVICES 1000-61203 ROAD INTERSECTIONS AND JUNCTIONS 1000-71204 PROGRAMME OF WORKS AND

    TEMPORARY WORKS 1000-71205 WORKMANSHIP AND QUALITY CONTROL 1000-81206 THE SETTING OUT OF WORK AND

    PROTECTION OF BEACONS 1000-81207 NOTICES, SIGNS AND ADVERTISEMENTS 1000-91208 METHODS OF MEASUREMENTS 1000-101209 METHODS OF P AYMENT 1000-101210 CERTIFICATE OF COMPLETION OF THE

    WORKS 1000-11

    1211 TRAFFIC OVER COMPLETED P AVEMENTL AYERS 1000-11

    1212 ALTERNATIVE DESIGNS AND OFFERS 1000-111213 V ARIATION FROM SPECIFIED NOMINAL

    R ATES OF APPLICATION OR NOMINALMIX PROPORTIONS 1000-12

    1214 CONTRACTOR’S ACTIVITIES IN RESPECTOF PROPERTY OUTSIDE THE ROADRESERVE AND OF SERVICES MOVED,D AMAGED OR ALTERED 1000-13

    1215 L AND ACQUISITION 1000-141216 INFORMATION FURNISHED BY THE

    EMPLOYER 1000-141217 PROTECTION OF THE WORKS AND

    REQUIREMENTS TO BE MET BEFORECONSTRUCTION OF WORK 1000-14

    1218 F AULTY WORK, REMEDIAL WORK 1000-151219 W ATER 1000-151220 AUTHORISED MEASUREMENTS AND

    TOLERANCES 1000-161221 DRAWINGS PROVIDED BY THE

    CONTRACTOR 1000-161222 USE OF EXPLOSIVES 1000-161223 WORK ON, OVER, UNDER OR

     ADJACENT TO R AILWAY LINES 1000-171224 THE H ANDING-OVER OF THE SITE 1000-171225 H AUL ROADS 1000-171226 MEASUREMENT OF DEPTH OF

    TRENCHES AND FOUNDATIONEXCAVATIONS 1000-17

    1227 ACCESS TO CONTRACTOR’S RECORDS,MONTHLY SITE MEETINGS AND

    PROGRESS PHOTOGRAPHS 1000-171228 LEGAL PROVISIONS 1000-181229 FINAL CLEARANCE 1000-181230 RECORDING OF INFORMATION

    RELATING TO CLAIMS FOR ADDITIONALCOMPENSATION OR EXTENSION OFTIME 1000-18

    1231 ELECTRICITY SUPPLY 1000-181232 POSITION OF WORKS 1000-181233 ACCESS TO SITE 1000-181234 COOPERATION AT SITE 1000-181235 ROADS AND SITE TO BE KEPT CLEAN 1000-181236 SECURITY OF THE WORKS 1000-181237 S AFETY 1000-181238 METHOD OF WORKING 1200-191239 MEASUREMENT AND P AYMENT 1200-19

    1201 SCOPE

    (a) GeneralThis Section covers matters which relate to the Contractas a whole. Definitions, phrases or wording which wouldotherwise require repetition in other sections of theSpecifications are also covered by clauses in thisSection. Matters covered by the Conditions of Contract

    are not repeated in this Section, except wherenecessary for providing more detailed information.

    (b) Modifications of and amendments to theStandard Specifications

    The Standard Specifications are to be read together with modifications, additions or amendments which arewritten in the Special Specifications.

    (c) Precedence of SpecificationsIn any case where there appears to be any conflictbetween the Standard Specifications and the SpecialSpecifications, the Special Specifications shall govern.

    1202 SERVICES

    (a) Location of Services

    The Contractor shall acquaint himself with the positionof all existing services, such as drains, undergroundand overhead telephone and electricity lines, ducts,poles, water mains, fittings, railway lines, etc. beforeany excavation or other work likely to affect the existingservices is commenced.

    The Employer will, in the Contract documents, provideinformation regarding the location of existing utilityservices, but the Employer does not acceptresponsibility for the accuracy of this information.

    The Contractor shall check and determine on the sitethe position of any services shown on the Drawings.This shall be done by consultation with owners of services, visual inspections, using detecting apparatusand by making excavations as required to expose theposition of the service. This shall also be done whereno services are nevertheless believed to be present.The positions of all services so detected shall bemarked carefully and then drawn in on the Drawings.These services will then be defined as known services.

    (b) Damage to Services

    The Contractor shall take all reasonable precautions notto damage the services during the search, when theonus shall rest with him to prove that, in the event of damage being done to such services during the search,it was not his fault that they had been damaged. TheContractor will be held responsible for any damagecaused by him to known services, unless he can provethat he has taken all the above precautions to thesatisfaction of the Engineer 

    The Contractor shall take all reasonable precautions toprotect existing services during construction and duringthe relocation of such services. Where protectivemeasures involve the construction of permanent work,the Contractor shall execute the work in accordancewith the Engineer’s instructions, and payment shall bemade as provided for in the Special Specifications.

     All pipes, cables, conduits or other known services of any nature whatsoever damaged as a result of theContractor’s operations shall be repaired and reinstatedforthwith by the Contractor or by the Authorityconcerned, to the satisfaction of the Engineer, all at the

    expense of the Contractor.

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    STANDARD SPECIFICATIONS FOR ROAD WORKS-2000 SERIES 1000 - GENERAL

    THE UNITED REPUBLIC OF T ANZANIA, MINISTRY OF WORKS P AGE 1000 - 7

    (c) Safety by overhead power lines

    Where work is to be carried out in the vicinity of overhead power lines, the Contractor shall ensure thatall persons working in such areas are aware of therelatively large distance that high voltage electricity can“short” to earth when cranes, or other large masses of steel, are in the vicinity of power lines. The Contractor shall be required to work outside the clearances statedin BS 162 which gives safe clearance for the various

    voltages.

    (d) Relocation of ServicesIt shall be clearly understood that, in certain instances,existing services can be relocated only after theContractor has advanced sufficiently on or hascompleted certain sections of earthworks or certainstructures. Whenever services are encountered whichinterfere with the execution of the Works and whichrequire to be moved and relocated, the Contractor shalladvise the Engineer, who will determine the extent of work, if any, to be undertaken by the Contractor inmoving, relocating and reinstating or protecting suchservices.

    The Contractor shall be responsible for arranging the

    removal or alteration of such services in conjunctionwith and to specifications of the relevant statutoryauthority subject to the prior agreement of the Engineer and where necessitated by the Works.

     A Provisional Sum for this work has been included inthe Bill of Quantities. Subject to prior agreement of theEngineer, and upon production of receipts, theContractor will be reimbursed the net cost of such workplus the percentage inserted by the Contractor in theBill of Quantities for his overheads and costs, in makingthe arrangement, for co-ordinating the work andeffecting payment.

    (e) Negotiations with owners of services

    The Contractor shall work in close co-operation with

    private Owners or public authorities controlling services,which have to be protected, moved or relocated.Details regarding the state of negotiations concludedbetween the Employer and the Owner at the time of bidding in respect of the time when either the Owner isprepared to start moving such services or when theContractor is required to or will be allowed to startmoving the services, and the duration of suchoperations, will either be stated in the bid documents or be made available to bidders. Further suchconsultations and negotiations with private owners or public authorities shall be carried out as required by theContractor. Should the Owners of services refuse toco-operate with the Contractor in a reasonable manner in connection with the protection or moving of servicesbelonging to them, the Contractor shall refer the matter 

    to the Engineer.

    (f) Programming relocation of services

    When the Contractor details his program of work asreferred to in the relevant clause of the Conditions of Contract, he shall, in consultation with the Engineer,clearly indicate as to when he proposes to start withand conclude the moving of each service or when hewill require the Owner to start with and conclude themoving of each service. Should it there after, throughdelays on the part the Employer or the Owner of theservice to be moved, be impossible to adhere to theprogramme of work, such programme shall be suitablyamended by the Contractor in consultation with theEngineer so as to limit, in so far as is possible, theextent of any damages or delays. Should it be

    impossible to limit entirely the damages or delaysresulting from the amendments necessary to theprogramme of work, the Contractor shall be reimbursedfor any additional costs incurred or damages sufferedby him.

    (g) Payment

     Any work required to be undertaken by the Contractor in protecting or moving and relocation of public servicesfor which no provision is made in the ContractDocuments, will be classified and paid for at DayworkRates, or if no applicable Daywork Rates exist, theContractor shall submit a quotation for the Engineer’sapproval.

    1203 ROAD INTERSECTIONS AND JUNCTIONSExcept where otherwise specified, no additionalpayment over and above payment for the various itemsof work included in this Contract will be made for theconstruction, in a confined space, of curves, tapers, bellmouths, traffic islands, farm accesses and other appurtenant Works in connection with the constructionand maintenance of road intersections and junctions.

    The Contractor shall be required to provide the safe andunrestricted flow of public traffic at all times during theconstruction and maintenance of such intersections and junctions.

    1204 PROGRAMME OF WORKS ANDTEMPORARY WORKS

    (a) Programme of worksIn accordance with relevant clauses of the Conditions of Contract and prior to commencement of permanentworks, the Contractor shall submit a fully detailed andtime related programme showing the order of procedureand method in which the Contractor propose to carryout the Works. The programme shall be so detailed asto show:

    −  The order of work.−  Planned rate of progress.−  Amount and type of equipment proposed.−  Details of methods to be employed.−  Details of Temporary Works.

    The programme shall not be in form of a bar chart only,but shall show clearly the anticipated quantities of workto be performed each month, as well as the anticipatedearnings for the various sections of work. Further it shallshow the critical path of activities.

    The Works shall be carried out so as to achieve acontinuous and consecutive output of fully completedroad. The order of execution of the Works shall besubject to reasonable adjustment as requested by theEngineer.

    Should the Contractor fall behind with the programmesubmitted by him in terms of the relevant clause of theConditions of Contract, which programme has been

    approved by the Engineer, or if the sequence of operations is altered, or if the programme is deviatedfrom in any other way, the Engineer may, withoutprejudice to the Employer’s rights in terms of therelevant clause of the Conditions of Contract, requirethe Contractor to submit, within seven days of the dateon which he has received a notice to this effect, arevised programme in terms of this Clause, whichindicates the manner in which the Contractor undertakes to complete the Works within the requiredtime. Any proposal in the revised programme toaccelerate the rate of progress shall be accompaniedby positive steps to increase production by more and/or better labour and equipment being provided on the siteor by the available labour and equipment being utilisedmore effectively.

    Failure on the part of Contractor to work according tothe programme or revised programmes, shall besufficient reason for the Employer to take steps asprovided for in the Conditions of Contract and shall be

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    construed, as not executing the Works in accordancewith the Contract.

    The approval by the Engineer of any programme shallhave no contractual significance other than that theEngineer would be satisfied if the work is carried out inaccordance with such programme and that theContractor undertakes to carry out the work inaccordance with the programme.

    (b) Temporary works

    The Contractor shall supply the Engineer with drawingsfor approval showing the layout and generalarrangement of all Temporary Works he proposes toconstruct for the purpose of the Contract including, butnot limited to:

    −  Camps, including accommodation for staff andlabour.

    −  Offices−  Laboratory−  Workshops−  Stores−  Aggregate crushing plants

      Bitumen storage facilities, etc.−  Concrete manufacturing plants−  Precast concrete yards−  Temporary river crossings−  Temporary bypass and access roads.

    No separate payment will be made for TemporaryWorks, the relevant cost being included in the rates of the Bill of Quantities for other work.

    1205 WORKMANSHIP AND QUALITYCONTROLThe onus rests with the Contractor to produce workwhich conforms in quality and accuracy of detail to allthe requirements of the Specifications and Drawings,and the Contractor shall, at his own expense, institute a

    quality control system and provide experiencedengineers, foremen, surveyors, materials technicians,other technicians and other technical staff, together withall transport, instruments and equipment, to ensureadequate supervision and positive control of the Worksat all times. The Contractor shall provide chainmen andlabourers as necessary for the Engineer to carry outchecks on the Works.

    The Contractor shall conduct tests or have themconducted continually on a regular basis, to check theproperties of natural materials and processed naturalmaterials and of products manufactured on the site,such as concrete and asphalt. Although not arequirement for the Contractor to conduct regular testson any commercially produced products such as

    cement, bitumen, steel and pipes, the Contractor shallremain fully responsible for any defective material or equipment provided by him. Similarly, the quality of allelements of the Works shall be checked on a regular basis so as to ensure compliance with the specifiedrequirements.

    The intensity of control and of tests to be conducted bythe Contractor in terms of these obligations is notspecified but shall be adequate to ensure that proper control is being exercised.

    Where any natural materials or products made fromnatural materials are supplied, and upon completion of each element of the construction work, the Contractor shall test and check such materials, products and/or 

    elements for compliance with the specifiedrequirements and shall submit his results to theEngineer for approval. Such submission shall includeall his measurements and test results and shall furnish

    adequate proof of compliance with the specifiedrequirements.

    No specific pay items are provided as compensation for the above obligations, including the provision of allsamples delivered to the Engineer, the repair of placesfrom which samples were taken, and the provision of the necessary personnel and testing apparatus andfacilities, for which compensation shall be included in

    the bid rates of the Contractor for the various items of work to which these obligations apply.

    The Contractor’s attention is also drawn to theprovisions of SERIES  7200 in regard to institutingspecific process-control systems. The Contractor'sattention is also drawn to the provisions of the varioussections of the Specifications regarding the minimumfrequency of testing that will be required to undertakeprocess control. The Contractor shall at his owndiscretion increase this frequency where necessary toensure adequate control.

    The Contractor shall submit to the Engineer for examination, the results of all relevant tests,measurements and levels indicating compliance with

    the Specifications on completion of every part of theWork.

    1206 THE SETTING OUT OF WORK ANDPROTECTION OF BEACONSThe Contractor’s attention is drawn to the requirementsof the relevant clause of the Conditions of Contract, andhe shall also comply with all legal provisions in regardto surveying and setting out work.

    The Contractor shall be responsible for the proper andaccurate setting out of the works as required in theContract documents. The Contractor shall provide allsurvey and measuring equipment and instrumentsnecessary for his use in the execution of the scheduledWorks.

    The Contractor shall allow in his bid rates for beingunable to use up to 30% of the Engineer’s control pointswhere such are provided in the Contract, through lossor damage occasioned prior to the commencementdate. When the Contractor requires the establishmentof a new control point or points due to the abovementioned loss or damage he shall advise the Engineer who will, if he deems it necessary, arrange for theestablishment of a new control point or points.

    Control points not affected by the works shall beprotected and preserved by the Contractor. In the caseof negligence on the part of the Contractor, or hisemployees, resulting in the destruction of control points,an amount equal to the cost of replacing the same maybe deducted from subsequent payments due theContractor.

    Control points affected by the works shall be offset bythe Contractor to the satisfaction of the Engineer.

    The Contractor shall, prior to any setting out, submit tothe Engineer for his approval, the method of setting outhe proposes to employ. The plan shall include theaccuracy, positions of the various types of stakes,method of marking stakes, and methods to be used for protecting stakes, etc. No survey work shall proceedprior to the Engineer's approval of the Contractor's plan. At least 24 hours before he intends to survey anyportion of the Works, the Contractor shall give writtennotice to the Engineer. Such notice shall include time,

    location and type of Works to be set out. The Contractor shall set out the Works and obtain approval of hissetting out before proceeding with construction.

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    In general, the Contractor shall check for the existenceof original marks, lines and levels of reference not lessthan one month prior to commencing works in anysection, to allow sufficient time for reinstatement of markings, and checking of lines and levels. Anydiscrepancies encountered shall be immediatelyreported to the Engineer, for instruction and co-ordination. The Contractor shall be deemed to haveallowed in his bid price for checking and reinstatement

    of original markings.

    Special care shall be exercised during construction notto damage, displace or disturb property andtrigonometrical survey beacons. If such beacons aredisturbed or destroyed by the Contractor they shall bereplaced without delay by a registered land surveyor atthe Contractor's expense. In cases where displacementof or damage to such beacons is unavoidable theContractor shall also be responsible for relocation or suitably referencing later reinstatement of such beaconat his own cost.

    The Engineer may if he deems it necessary, revise theline and grade and will require the Contractor to adjustthe stake-out accordingly.

    The Contractor shall check the condition of all referenceand level beacons and shall satisfy himself that theyhave not been displaced and are true in regard toposition and level. If beacons have been destroyed,displaced or damaged before the site is handed over tothe Contractor, the Engineer will arrange to have newbeacons installed. A beacon, which has been displaced,shall not be used unless its true position and level havebeen re-established and the new values verified by theEngineer.

    Where a beacon is likely to be displaced duringconstruction operations, the Contractor shall establishsuitable reference beacons at locations where they willnot be displaced during construction. No beacon shall

    be covered over, displaced or destroyed beforeaccurate reference beacons have been established anddetails of the positions and levels of such beacons havebeen submitted to and approved by the Engineer. TheContractor’s reference beacons shall be of at least thesame quality and durability as the existing beacons.

    The Contractor shall submit to the Engineer the methodof setting-out he proposes to employ. To ensurebeyond all doubt that the complex elements of the road,such as traffic interchanges, structures and other important features are located truly and correctly, theContractor shall check all setting-out by a secondmethod. The Engineer may at any time request theContractor to submit proof that his setting-out has beensatisfactorily checked.

    In cases where the displacement of or damage toproperty beacons or trigonometrical survey beacons isunavoidable, the Contractor shall notify the Engineer ingood time so that he may arrange to have suchbeacons suitably referenced and later on reinstated.The cost of such work, if paid for by the Contractor,shall be reimbursable as extra work, as provided for inthe Conditions of Contract.

    For the purposes of this Clause and of the relevantclause of the Conditions of Contract, any beacon madefrom a metal peg cast in concrete and any boundarybeacon, whether or not cast in concrete, shall beregarded as a beacon. Centre-line pegs shall not beclassified as beacons.

    To protect beacons, the boundary fences of the roadreserve shall be splayed at corners so as to avoid theuse of corner posts in the same position as property or 

    trigonometrical survey beacons, all as shown on theDrawings.

     Accurate control of line and level shall be provided bythe Contractor at all stages of construction as detailedin SECTION 7300 of these Specifications.

    Where directed by the Engineer, the Contractor shallprovide to the Engineer camber boards to the profile of 

    the normal camber, 3.0 m long straight edges andmeasuring wedges.

    The camber boards shall be constructed of stout timber,angle iron or metal tubes so as to span 6.5 m withoutdeflection, and preferably supported on trollies andfitted with a device for raising and lowering the board.The bottom of a timber board shall be shoed with steelplate, the width of the timber, and at least 5 mm thick.The construction of the boards shall be to thesatisfaction of the Engineer.

    The 3.0 m long straight edges and measuring wedgesshall be made of durable strong materials such thatthey are inflexible and will not warp and do not suffer from abrasion.

    The setting-out of work will not be measured and paidfor separately, and compensation for the work involvedwill be deemed to be covered by the rates bid and paidfor in the various items of work included in this Contract.No separate payment will be made to the Contractor for the provision of camber boards, straight edges andmeasuring wedges, their cost being included by theContractor in his rates in the Bill of Quantities.

    No separate payment will be made for stake-out,adjustments to the stake-out, or to establish andcompute new points/benchmarks the relevant costsbeing deemed to be included in the bid rates for other items in the Bill of Quantities.

    1207 NOTICES, SIGNS AND ADVERTISEMENTSThe Contractor and subcontractors shall not erect anysigns, notices or advertisements on or along the Worksor the site of the works without the approval of theEngineer or according to format given by the Engineer.

    No sign boards other than those specified above will bepermitted on or adjacent to the Works, except that theContractor may permit each of his sub-contractors todisplay one, and only one, signboard of less than 2 m

    2 at

    the works office.

     At each end of the Works the Contractor shall provideand erect, as part of his obligations under SECTION1300, and on approved locations, at the starting andending points of the Works, sign boards of sound,weather proof construction, painted by an approved firmof sign writers in accordance with the details shown onthe Drawings.

    These signs are to be erected not later than one monthafter the Contractor has been given access to the site.

    The Engineer shall have the right to have any sign,notice or advertisement moved to a better position or tohave it removed from the site of the Works if it should inany way prove unsatisfactory, inconvenient or dangerous to the general public.

     All advertisements, notices and signs shall be removedby the Contractor upon issuance of the final certificate

    of completion.

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    1208 METHODS OF MEASUREMENTS

    (a) Units of measurements

      All work shall be measured in accordance with the SIsystem of metric units. (b) Bill of Quantities

     The quantities set out in the Bill of Quantities are

    estimated quantities and are used for the comparison of bids and for awarding the Contract. It must be clearlyunderstood that only the actual quantities of work doneor materials supplied will be measured for payment, andthat the scheduled quantities may be increased or decreased as provided for in the Conditions of Contract. (c) Measurement of completed Work

     All distances along the centre line of the road as shownon the Drawings are horizontal distances, which will beused in calculating the quantities of fill and pavementlayers for purposes of payment. All cross-sections shallbe taken in a vertical plane.

    No material shall be measured in the vehicle for payment purposes.

    The quantity of bituminous and similar materials to bepaid by volume shall be measured at the temperature of application and paid for in accordance with approvedapplication rates.

    The quantity of bitumen in mixes and stabilisers incemented materials shall be paid by mass inaccordance with approved mix design proportions.

    Structures shall be measured to the neat lines shownon the Drawing and shall include any changes orderedin writing by the engineer and, for purposes of payment,the calculated volume of concrete structures shallinclude the volume of reinforcing steel, and minor ductsup to 150 mm in diameter.

    1209 METHODS OF PAYMENT

    (a) Contract ratesIn computing the final Contract amount, payment shallbe based on the actual quantity of authorised workdone in accordance with the specifications anddrawings. The bid rates shall apply, subject to theprovisions of the Conditions of Contract, irrespective of whether the actual quantities are more or less than thescheduled quantities.

    Where no rate or price has been entered against a payitem in the Bill of Quantities by a bidder it shall beunderstood that he does not require any compensationfor such work. Where, however, a pay item describedin these Specifications or in the Special Specificationsdoes not appear in the Bill of Quantities, the Contractor will receive reasonable compensation for such work if required, unless anything to the contrary has beendetermined elsewhere.

    (b) Rates to be inclusive

     The Contractor shall accept the payment provided for inthe Contract and represented by the rates bid by him inthe Bill of Quantities, as payment in full for executingand completing the work as specified, for procuring,furnishing, placing and installing all materials, for procuring and providing labour, supervision,constructional plant, tools and equipment, for wastage,transport, loading and off-loading, handling,maintenance, temporary work, testing, quality control

    including process control, overheads, profit, risk andother obligations and for all other incidentals necessaryfor the completion of the work and maintenance duringthe period of maintenance.

     The Contractor shall note that the cost of all Works andmaterials for minor construction details at bridges, for example small quantities of caulking compound and joint filler (other than expansion joints), anchor-bar covers, etc, not shown in the Bill of Quantities, shall beincluded in the bid rates for concrete. This CLAUSE  shall apply in full to all pay items exceptwhere these requirements may be specifically amended

    in each case. 

    (c) The Meaning of certain phrases in paymentclauses

     (i) Procuring and furnishing (material). Where any of the words “supply”, “procure”,“provide”, “provision of”, “furnish (material)”, areused in the description of a pay item, it shall meanthe supply and delivery to the point of use of allmaterials of any kind required for the work coveredby the particular pay item, including all tax,purchase costs, claims, damages, royalties andtransport costs involved, but excluding overhaul. Inthe case of borrow materials, stone and sand, it

    shall also include all negotiations with the Ownersconcerned, excavating, producing, preparing,processing, testing, hauling and delivering thematerial to the point of use; the construction, repair,maintenance and making good after completion of all access roads, and all work required in opening,using and finishing off borrow pits unless coveredby other pay items in the Bill of Quantities.

     (ii) Placing Material

     The phrase “placing material” shall mean the off-loading, spreading, blending, processing, watering,mixing, shaping and compacting (where specified)of the material in the pavement layer, fills andbypasses, as well as the procuring, furnishing,applying and admixing of water, the breaking-down

    of oversize material, the removing of oversizematerial which cannot be broken down, correctingirregular or uneven surfaces or layers, the thicknessof which is not to specification, finishing-off towithin the specified tolerances, the refilling of testholes and maintaining the completed work. In thecase of asphalt course and bituminous seals, itshall also mean the heating and spraying of binder,the spreading of aggregate or asphalt mixtures,rolling, compacting, finishing-off to within thespecified tolerances, and maintaining the completedwork.

     The phrase, “procuring, furnishing and placing”shall mean procuring and furnishing in addition toplacing, all as defined herein.

     (d) Pay Items The description under the pay items in the varioussections of the Specifications, indicating the work for which allowance shall be made in the bid rates for suchpay items, are for the guidance of the Contractor anddo not necessarily repeat all the details of work andmaterials required by and described in theSpecifications. These descriptions shall be read in conjunction with therelevant Specifications and Drawings, and theContractor shall, when bidding, bear in mind that hisrates shall be inclusive as specified in SUBCLAUSE  (b)above. 

    (e) Materials on the Site Payment in terms of the relevant clause of theConditions of Contract for materials on the site, whichhave not yet been incorporated in the works, will becalculated at 80% of their purchase price, or, in the

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    case of crushed stone which has not been purchasedbut has been produced on the site, at 50% of the bidrate for such material. The Engineer may at his sole discretion allow paymentunder “materials on the site” in respect of articles suchas precast beams manufactured and stored off site,subject to their having been completed, to proof of their ownership as being that of the Contractor, and to the

    articles being clearly marked with the Contractor’sname, the Contract number and other particulars inaccordance with the Engineer’s instructions. (f) Rate-only items

     Against an item in the Bill of Quantities where noquantity is given but a rate only is required, theContractor shall fill in a rate or amount which willconstitute payment for work which may be done interms of this item. Such rate only item is used where itis estimated that little or no work will be required under the item, or where the item is to be considered as analternative for another item where a quantity is given,or for variations in rates of application or mixproportions in terms of CLAUSE 1213.

    Work under rate-only items will be paid for only if it hasbeen executed in terms of a written instruction by theEngineer.

    (g) Provisional Sums

    The Bill of Quantities may contain Provisional Sums, sodesignated, which are entered as a preliminaryallowance to cover the cost of work, materials, goods or services to be provided by the Contractor and whichhave not been fully specified or measured or to cover the cost of unforeseen items of work or contingentexpenditure, for which no rates are applicable but for which the Contractor is to be paid according to theapplicable provisions of the Contract.

    Work done under such Provisional Sums shall only be

    executed upon a written order by the Engineer whichorder shall also specify the method of payment. Theexpenditure in respect of a Provisional Sum for workordered by the Engineer shall be entirely at hisdiscretion and any final expenditure in respect of aProvisional Sum may be more, less or equal to theamount provided in the Bill of Quantities.

    Payment as specified in the order given by the Engineer shall be either at contract rates, where such areapplicable, or where none is applicable, the Contractor shall submit a separate quotation to the Engineer.

    (h) Retention money

     All payments are subject to deduction of RetentionMoney, as provided in the Conditions of Contract.

    1210 CERTIFICATE OF COMPLETION OF THEWORK A certificate of completion of the Works (Taking Over Certificate) in terms of the relevant clause of theConditions of Contract will be issued only if thefollowing sections of the Works as may be applicablehave, inter alia, been duly completed.−  the gravel wearing course, seals, asphalt or 

    concrete pavement.

    −  all above-ground and subsoil drainage structure−  all fencing.−  the finishing-off of medians and slopes of cuts and

    fills−  all the necessary road signs and road-surface

    markings.

    −  all guard-rails−  all structures.

    1211 TRAFFIC OVER COMPLETED PAVEMENTLAYERSTraffic over structures or pavement layers of anuncompleted road shall, in addition to other restrictionsspecified elsewhere, be restricted to equipmentrequired for its construction, with the provision thattraffic for hauling material over pavement layers, in sofar as is possible, shall be limited to a minimum by the

    use of construction roads and deviations.

    Traffic over all public roads, structures or the completedroad will be restricted to the maximum axle loadpermitted in terms of statutory provisions. Any damagecaused by the Contractor’s traffic shall be repaired athis own cost.

    1212 ALTERNATIVE DESIGNS AND OFFERSUnless anything to the contrary has been determinedelsewhere in the Contract documents, a bidder may,together with his bid for the original designs containedin the Contract documents, submit alternative designsand offers for consideration. Such alternative designsand offers shall be subject to the following conditionsand requirements.

    (a) Bids

      An alternative offer or design will be considered only if the bid for the original items has been fully priced andcompleted. Unless the alternative offer stipulates to the contrary, itshall be assumed that the period for completion of theWorks shall be the same as for the original design.  An alternative offer or design shall be submittedtogether with the bid for the original items or design,otherwise it will not be considered when bids areadjudicated. Calculations, drawings and a modified Bill of Quantities

    (as determined hereafter) in respect of each alternativeoffer or design shall accompany the alternative bidoffer. (b) Design codes

      Alternative designs shall be executed strictly inaccordance with the appropriate design codes andprescriptions of the Employer. Copies of such codesand prescriptions will be available for perusal at theoffice of the Engineer, but the onus rests with theContractor to ensure that he complies with the designrequirements of the Employer. (c) Preliminary calculations

     Preliminary calculations for an alternative design shallbe submitted with the bid. Such calculations shall give

    adequate details so as to enable an assessment to bemade of the general efficacy of the design and of itsprincipal elements, also of the degree to which thedesign prescriptions and codes of the Employer arebeing complied with. The calculations shall be clear and in a logical sequence and shall clearly reflect all thedesign assumptions. (d) Preliminary drawings

     Preliminary drawings of the alternative designs shallalso be submitted with the bid. These drawings shallcomprise adequate layout plans, elevations andsections and shall clearly illustrate the general efficacyof the design and its principal elements. Foundationdepths and other elements depending on foundationconditions shall, in so far as may be applicable, be inaccordance with foundation particulars appearing in theContract document. Drawings for alternative designs shall be prepared inaccordance with the provisions of CLAUSE 1221.

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    (e) Quantities

     Each alternative offer shall be accompanied by amodified priced Bill of Quantities compiled inaccordance with the Standard Specifications, in so far as it is applicable. In addition to the Bill of Quantities, aset of calculations shall be supplied to show how thequantities have been determined. All assumptions inregard to foundation conditions or other factors whichwill determine quantities shall be clearly and

    conspicuously marked by underlining or colouring, andshall indicate whether or not the assumptions havebeen based on information furnished in the Contractdocuments (with the necessary references). (f) Further detai ls

     Should the Engineer find that the calculations anddrawings submitted for alternative designs are notcomplete enough for proper adjudication of thealternative designs, it may mean that no further consideration will be given to such alternative designs.The Employer, however, reserves the right to call on thebidder to submit such further calculations and drawingsas may be required. If such further details are notsubmitted within ten days of having been requested, thealternative designs may possibly not be given further 

    consideration (g) Preliminary adjudication of alternative designs

     The Engineer will undertake a preliminary scrutiny of any alternative designs for compliance with thespecified requirements of the Employer. Should he findany mistakes or unsatisfactory aspects, he may affordin the Contractor the opportunity to rectify them within aperiod to be determined by the Engineer. However, it isemphasised that the preliminary scrutiny of the designand bid by the Engineer, by its very nature, cannot becomprehensive, and no guarantee can be given in thisregard that all the mistakes made by the Contractor willin fact be detected. Any correction of such mistakesshall be made with the bid price of the Contractor beingretained, and, wherever necessary, the priced Bill of 

    Quantities for the alternative design shall be adjustedaccordingly. (h) Acceptance of alternative design

    The Contractor shall note that the acceptance of a bidwhich includes alternative designs shall mean that thealternative designs have been approved in principleonly. If the final calculations, drawings and details donot comply with the specified requirements, suchalternative designs may be rejected, unless they aresuitably amended by the Contractor so as to beacceptable to the Engineer.

    (i) Final drawings and calculations and the price.Bill of Quantities

    Where a bid with an alternative design has been

    accepted, the Contractor shall, not less than threemonths before he intends starting with the constructionof such design, submit to the Engineer a complete setof working drawings, detailed calculations and acomplete Bill of Quantities, for approval. The Bill of Quantities shall be based on the preliminary Bill of Quantities, but with the necessary adjustments inquantities and prices and with the bid price for thealternative design being retained.

    Within six weeks of having received the above, theEngineer will indicate which drawings, calculations,quantities, prices and other particulars are acceptableto him and which not, with reasons furnished. TheContractor shall then submit to the Engineer in goodtime any modified drawings and other particulars for 

    approval, for which he will require two weeks. Any delayarising from the fact that the amended particulars do notmeet the requirements shall be the responsibility of theContractor.

    No work which will be affected by an alternative designmay be commenced, unless the Drawings, Bill of Quantities and prices for such alternative design havebeen approved. Should the Contractor fail to modify anydrawings, calculations, quantities, prices or any other particulars to the satisfaction of the Engineer, thealternative design will be rejected and the originaldesign shall be constructed for the same amount as hasbeen bid for the alternative design.

    (j) Responsibility for alternative design

    The approval of a design by the Engineer shall in noway relieve the Contractor of his responsibility toproduce a design which conforms in all respects to allthe specified requirements and which will be suitable for the purpose envisaged.

    Should it appear later during construction or during themaintenance period that the design does not conform tothe specified requirements, the Contractor only shall beliable for any damage arising therefrom and he shall, athis own expense, do all the necessary work to ensurethat the structure conforms to all the specifiedrequirements.

    (k) Payments for alternative design Payments for alternative designs will be based on thefinally approved Bill of Quantities and rates for suchdesigns. The lump sum for an alternative design willremain fixed and will be the final amount payable to theContractor in regard to such design, except only for deviations arising from:

    −  foundation conditions which differ from foundationconditions shown in the contract documents, or inregard to assumptions regarding foundationconditions stated in his bid by the Contractor andaccepted by the Engineer.

    −  changes not arising from any failure or fault of theContractor, but from modifications requested by theEngineer.

     (l) Cost of checking alternative designs The Contractor shall, in his bid for each alternativedesign, include an item to cover the cost for checkinghis design. This item shall be 5% of the bid amount of the design without any price adjustment in terms of therelevant clause of the Conditions of Contract beingconsidered, and the amount will be payable to theEngineer only upon an authorisation issued by theEmployer. (m) Alternative Offers

     Alternative offers in this context shall mean offers notrelating to a structure, such as a bridge, which requiresa comprehensive structural analysis. It involves, in themain, offers for the use of other materials, constructionprogrammes, alternative routes, etc. In this case the

    provisions of CLAUSE 1212 will still apply, except in thecase where the Employer may agree to amend or delete certain of the provisions, depending on thenature of the offer, but subject to a written agreementbeforehand with the Employer.

    1213 VARIATION FROM SPECIFIED NOMINALRATES OF APPLICATION OR NOMINALMIX PROPORTIONSThe various sections of these specifications specifynominal rates of application or nominal mix proportionsfor materials such as bituminous materials, aggregates,fillers, stabilising agents, paint and the like. Biddersshall base their bids on these nominal rates of application and mix proportions.

    Where such nominal rates of application or mixproportions are specified, provision is made for deviations in the quantities of material in consequenceof the rates of application or mix proportions prescribed

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    by the Engineer in each particular case in considerationof the available materials and the conditions on the site.

    Where the actual rates of application or mix proportionsused in the works vary from the specified nominal ratesand mix proportions, adjustment of compensation willbe made:

    −  as a payment to the Contractor in respect of anyauthorised increase in quantities which exceedthose specified, where such increase has beenordered, in writing, by the Engineer 

    or 

    −  as a refund to the Employer in respect of thedecrease in quantities which are less than thosespecified, irrespective of whether such decreaseresults from an authorised decrease in the rates of application or mix proportions, or from unauthorisedreduction on the part of the Contractor.

    Payment for a prescribed rate of application or mixproportion shall be based on the actual rate of application or mix proportion used, provided that thisdoes not exceed the prescribed rate of application or mix proportion, plus any tolerance in the rate of 

    application or mix proportion allowed. If the actual rateof application or mix proportion is below the prescribedrate of application or mix proportion ordered, paymentshall be based on the actual rate of application or mixproportion regardless of any tolerance allowed.Notwithstanding the above, the Engineer shall be fullyentitled to reject work which has not been constructedin accordance with the specifications or the rate of application or mix proportions prescribed by him.

    The Employer shall be refunded for any decrease in thespecified rates of application or mix proportions at thesame rate per unit of measurement as that bid by theContractor for additional materials required by anincrease in the rates of application or mix proportions.

    1214 CONTRACTOR’S ACTIVITIES INRESPECT OF PROPERTY OUTSIDE THEROAD RESERVE AND OF SERVICESMOVED, DAMAGED OR ALTERED

    (a) Statutory provisions

    The Contractor shall exercise any rights that may beceded to him by an Authority in terms of any statutoryprovisions for purposes of executing the Contract, oncondition that:

    (i) the Contractor complies strictly with therequirements of such statutory provisions,particularly in regard to the matters relating to

    serving notice on the Owner or consultation withhim.

    (ii) In each case a written agreement is made with theEngineer regarding the details of the Contractor’sproposed actions before the rights of the Contractor in terms of the statutory provisions are exercised.

    (b) Agreements with Owners or Legal Users of property

    The Contractor shall put in writing all his agreementswith Owners of property outside the road reserve or of services inside or outside the road reserve in respect of the following matters:

    (i) The location, extent and use of borrow pits, haul

    roads, construction roads and bypasses outside theroad reserve.

    (ii) Compensation, if applicable, for land or materialstaken or for land temporarily used or occupied.

    (iii) The reinstatement of property occupied, used,damaged or destroyed, or compensation therefor inlieu of reinstatement.

    (iv) The procedure for the moving of services anddetails as to how and when this is to be done.

    (v) Any similar matter directly related to theContractor’s activities on or in respect of private

    property or services.

    These agreements shall be signed by all the partiesconcerned and delivered to the Engineer.

    Where the Contractor cannot obtain the Owner’sagreement in writing, he shall refer the matter to theEngineer and shall furnish him with details, in writing, of any verbal agreement made.

    (c) Notice on owner 

    Where, in addition to any agreement with the Owner of any property to be entered upon or temporarilyoccupied or any service to be moved, it is understood or required that the Contractor shall serve notice on theOwner immediately before actually entering upon or 

    occupying the private property or moving a service,and shall give proper notice thereof in writing, and theEngineer shall be supplied with a copy of such notice,together with acknowledgement of receipt. (d) Completion statement from owner 

    On completion of his operations, the Contractor shallobtain, from the owner concerned, a written statementto the effect.

    (i) that the Contractor has fulfilled his obligations under a written agreement

    (ii) in the absence of a written agreement, that theOwner has received all the compensation he isentitled to and is also satisfied that all property

    occupied, including borrow pits, haul roads andconstruction roads, has been properly restored andis in a satisfactory condition.

     All such statements shall be signed, dated anddelivered to the Engineer.

    (e) Use of land outside provided area

    Should the Contractor wish to use land outside the areaprovided by the Employer for storing or keepingmaterial or equipment required for the construction of the permanent works, it will be subject to the following:

    (i) That the Engineer approves any area selected for this purpose.

    (ii) That such land be physically separated from anyproduction plant or activities and suitably fenced in.

    (iii) That the area used for the aforesaid purpose besurveyed, and, where the land does not belong tothe Contractor, he shall enter into a contract of lease with the Owner of such land in respect of thefull period for which such land shall be used for such purpose,

    (iv) Which contract shall stipulate that the Owner shallnot have any right whatsoever to any materialstockpiled on such land during the currency of thecontract of lease. That suitable, permanentreference beacons, approved by the Engineer, beplaced next to the area, at the cost of the

    Contractor, for use by the Engineer with a view to, if applicable, taking cross-section for determiningquantities.

    (v) That only material use for this contract shall be

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    stored on such land.

    (f) Fences, gates and signs (private)The Contractor shall be responsible for ensuring thatlivestock cannot stray as a result of his operations or enter a construction area including borrow areas. Whenexisting fences and gates have to be removed or altered for the proper execution of the Works or arerequired to exclude livestock, the Contractor shall, at his

    own expense, erect temporary fencing and gates, and if necessary, provide watchmen to ensure that livestockcannot stray. New tension wires shall be used when re-erecting existing mesh fences. For permanentlyrelocated existing fences and new fences, eachhorizontal wire shall be tensioned between bracedposts using a wire strainer. Each wire shall also besecurely fixed to each post using wire ties throughdrilled holes.

    The permanent relocation of existing fences and privatesigns and the construction of new permanent fences asshown or as directed by the Engineer shall be paid for at the contract price per unit of measurement shown inthe Bill of Quantities which price shall include for furnishing and placing all materials, including all labour,

    equipment, tools and incidentals necessary to completethe work.

    1215 LAND ACQUISITION All land to be permanently used or occupied by theWorks will be provided by the Employer, but theapproval of the Engineer must be sought before entryupon the land.

    In all cases, the Contractor shall be required to make allnecessary arrangements with local authorities andowners or legal occupants of the land and to pay thecost of compensation on behalf of the Employer. For this purpose, the Contractor will liaise with the regionaladministration or the appropriate authority and advise of the intention to commence work of any kind.

    The Employer will refund to the Contractor suchpayments, as provided in the Bill of Quantities, and alllands so purchased shall be the property of theEmployer.

    The attention of the Contractor is drawn to theprovisions of CLAUSE 1214 as regards his activities onprivate land and to SECTION 3400 for acquisition of landfor borrow pits, quarries and temporary works.

    The Contractor shall observe all the legal provisionsand the provisions of the Special Specifications inrespect of his activities at borrow pits and whenfinishing off the borrow pits.

    The Contractor shall satisfy himself that all necessarynegotiations have been made with the Owner or LegalOccupants of the ground prior to entry.

    1216 INFORMATION FURNISHED BY THEEMPLOYERCertain information contained in these contractdocuments or provided separately is being offered ingood faith, but, in the circumstances pertaining to thetype of information furnished, no guarantee can begiven that all the information is necessarily correct or representative of the in situ condition.

    This applies more specifically to all soil tests, soilmapping, drilling results, geophysical survey, geologicalreports, borrow-pit information, material surveys andreports, and similar information, the accuracy of whichis necessarily subject to the limitations of testing,sampling, the natural variation of material or formationsbeing investigated and the measure of certainty with

    which conclusions can be drawn from anyinvestigations made. It also applies to any materialsutilisation plan provided, as the diagram may be subjectto major alterations during the progress of the work,depending on site conditions.

    The Employer will not accept any liability for thecorrectness or otherwise of the information furnished or for any resulting damage, whether direct or 

    consequential, should it appear, during the course of the Contract, that the information supplied is either incorrect or not representative.

    1217 PROTECTION OF THE WORKS ANDREQUIREMENTS TO BE MET BEFORECONSTRUCTION OF WORK

    (a) Nature of ground and condition of workThe Contractor must satisfy himself as to the generalcircumstances at the site of the Works and theconstruction thereon, the form of river beds, and banks,the flows in the rivers, the surface of the ground andnature of the materials to be excavated, the possibility

    of subsidence from soft ground and bad and brokenmaterials, and falls of rock in or arising out of theWorks, and the possibility of floods and landslides, andthe rates and prices in the Bill of Quantities will be heldto cover all such contingencies.

    In order to minimise the possible adverse effects of flooding the drainage of the natural ground in thevicinity of the earthworks and the drainage worksgenerally shall be carried out in advance of the rest of the Works.

    (b) LandslidesThe removal of materials in slips, slides or subsidencesand overbreaks of rock extending beyond the lines andslopes or below the levels shown on the Drawings or 

    required by the Engineer will not be paid for unlesssuch occurrences were, in the opinion of the Engineer,beyond the control of the Contractor and could not havebeen prevented by the exercise of due care anddiligence.

    Where payment is made for the removal of suchmaterials, it will be paid as a variation at the appropriaterate inserted in the Bill of Quantities having regard tothe condition and situation of the material at the time of removal and regardless of its condition and situationprior to the slip.

    (c) DrainageThe provision of temporary drainage work such asdrains, open channels, banks, etc and providing and

    operating temporary pumps and such other equipmentas may be necessary for adequately protecting,draining and de-watering the Works and temporaryworks. This will be in addition to any permanentdrainage works specified and installed, and in additionto any temporary drainage works specifically paid for separately as in the case of deviations.

    (d) Damage by wet material

    Material in borrow pits shall not be allowed to becomeexcessively wet. All completed layers shall be properlydrained, dumps of material on completed layer workshall not inhibit surface drainage or form wet spotsunder and around dumps, and all parts of the Worksshall be protected against erosion by floods and rain.

    Material shall not be spread on a layer that is so wet asto result in the danger of any damage being caused tothe layer during compaction of a subsequent layer, or when opened to traffic.

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    When material is spread out on the road, the Contractor shall ensure that, during wet periods, it will have a goodcross-fall and a light compaction on the surface in order to facilitate run-off during rainy weather.

    (e) Fill and cut slopesFill and cut slopes shall be repaired immediatelywhenever damaged by surface water. Where erosionoccurs on high fills, the slopes shall be repaired by

    cutting back to form benches and by compacting thebackfill mechanically to the specified densities, usingsuitable light equipment. (f) Excavations

    Excavations for pipe drains, culverts, service ducts andsimilar structures shall be adequately protected againstthe possible ingress of water during rainstorms. (g) Completed layer work

     All completed layer work shall be protected andmaintained until the following layer is constructed.Maintenance shall include immediate repairs to anydamage or defects which may occur and shall berepeated as often as may be necessary to keep thelayer continuously intact and in good condition.

     (h) Preparation of layer work

    Before any completed layer is primed or a succeedinglayer is constructed thereon, any damage to the existinglayer shall be repaired, so that, after repair or reconstruction if necessary, it will conform in allrespects to the requirements specified for that layer. Allrepair work other than minor surface damage repairsshall be submitted to the Engineer for inspection beforeit is covered up.

    The previously constructed layer shall be thoroughlycleaned by the removal of all foreign material beforeconstruction of a succeeding layer or application of aprime coat, surfacing or surface treatment. In the caseof all bituminous work in particular, the existing layer 

    shall be thoroughly broomed and all dung, clay, mudand other deleterious material completely removed.Where necessary, the surface shall be sprayed withwater before, during and after brooming to remove allforeign material.

    Work performed as part of the above obligations shallnot be measured and paid for separately, and the costthereof shall be included in the rates bid for the variousitems of work requiring protection and the items for theContractor’s establishment on the site, as specified inSECTION 1300.

    1218 FAULTY WORK, REMEDIAL WORK

    (a) General Any work which fails to comply with the Specificationsshall be rejected and the Contractor shall, at his ownexpense, make good any defects, as directed by and tothe satisfaction of the Engineer.

    When any part of the Works or any equipment or material is found, upon examination by the Engineer,not to conform to the requirements or at any stagebefore final acceptance is damaged so that it no longer conforms to the requirements of the Specifications, theEngineer may order its complete removal andreplacement, at the Contractor’s expenses, withsatisfactory work, equipment or material, or he maypermit the Contractor to apply remedial measures inorder to make good any such defects or damage. The

    actual remedial measures taken shall at all times beentirely at the Contractor’s own initiative, risk and costs,but subject to the Engineer’s approval regarding thedetails thereof.

    In particular, remedial measures shall ensure fullcompliance with the requirements of the Specificationsof the final product, shall not endanger or damage anyother part of the Works, and shall be carefully controlledand submitted to the Engineer for examination whencompleted or at any intermediate stage as may berequired.

    For the guidance of the Contractor, an indication is

    given below of what would normally be required in themore common cases of defects or damage, but theEngineer will in no way be bound to accept or approvethe measures given below, as the actual remedialmeasures will be dictated by the circumstances of eachparticular case.

    (b) Earthworks

    (i) Where a cut slope has been over excavated or undercut or where the floor of a cutting has beentaken too deep, back filling and re-compaction shallbe carried out as set out in SECTION  7400. Allnecessary measures shall be taken to drain awaygroundwater that may accumulate in back filled

    sections.

    (ii) Excess width of fills shall to be trimmed down if required by the Engineer.

     (iii) Where erosion has damaged the surface of cuts or 

    fills, the damage shall be made good by back fillingwith suitable material and re-trimming. In moreserious cases in the opinion of the Engineer, theslopes shall be cut back by benching, back filledand compacted to the required standard of compaction with suitable light equipment and thenre-trimmed, all in accordance with SECTION 7400.

    (c) Stabilising

      Any sections failing to meet the requirements specified

    or damaged to the extent that they require breaking-upand re-compaction will have to be re stabilised with thetype and quantity of stabilising agent ordered by theEngineer. The Engineer may also order that the layer be removed entirely and replaced with fresh material tobe stabilised. (d) Local defects in pavement layers

     Where remedial measures are taken to make goodlocal defects, the width of the area to be repaired bymachines shall be such as will be necessary toaccommodate the full width of the machines used, andit shall be of a reasonable length to ensure effectiveoperation by the machinery. The depth to whichmaterial will have to be removed will depend on thetype of material. Gravel will require breaking up to a

    depth of at least 75 mm and crushed stone will usuallyrequire breaking up over its full depth. Asphalt materialwill normally require removal over its full depth. (e) ConcreteConcrete work will normally require the cutting-backand complete removal of any weak or honey combedsections and making good by using special epoxyadhesives to bind fresh concrete to old concrete.Cracks, when permitted to remain, shall be injected withsuitable epoxy compounds, and test cores shall then bedrilled for testing the efficacy of the injection process.

    1219 WATERIt is the Contractor’s responsibilities to provide cleanand sufficient supply of fresh water for both construction

    purposes and also for all the houses, camps, offices,workshops, laboratories, etc.

    The construction water shall be clean, free fromsuspended solids and undesirable concentrations of 

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    deleterious salts and from any matter in quantitiesconsidered by the Engineer to be deleterious to theproposed work. The water shall be applied at thelocation, in the amounts, and during the hours, includingnights, as directed by the Engineer.

    The distributors used for watering shall be equippedwith spray bar and shall be of ample capacity and of such design as to ensure uniform application of water in

    the amounts directed by the Engineer.

    Wa