6.1 STEPS INVOLVED
The various steps involved and the agency responsible for the Project Preparation are given below:
|Estimate Length of Roads for
New connectivity and/or Upgradation
Distribution of State’s Allocation among Districts
Selection of list of proposals in each district
Vetting of list of proposals for each year & Administrative approval
Preparation of DPRs
Scrutiny of DPRs
State Nodal Department
District Panchayats, with assistance of PIU
State-level Standing Committee with assistance of SRRDA
6.2 DETAILED PROJECT REPORT (DPR)
Each Rural Road Project (whether a new link or upgradation of an existing road) should have a separate Detailed Project Report (DPR).
The DPR should be based on detailed survey and investigations, design and technology choice and should be of such detail that the quantities and costs are accurate, and no cost over-run takes place due to changes in scope of work or quantities at the time or execution. Guidance may be taken from IRC: SP: 19 for preparing the DPR.
Before the commencement of the preparation of the DPRs, a joint meeting of all concerned Engineers of PIUs and STA(s)/ PTA shall be convened by the SQC under the Chairmanship of the Chief Engineer (PMGSY) to discuss the issues and the data requirements for the preparation of DPR. At this stage STA/ PTA shall take initiative in guiding Executing Agencies for adopting designs with New Materials where it is possible. If needed, they will associate in the investigations of special nature. The Engineers also will be appraised of the need for appropriate Designs with respect to Geometrics, Pavement Crust, Surface Drainage, CD Works as well as the measures for Environmental Conservation.
The steps involved in the preparation are as under:
|1.||Selection of alignment||:||The suitability of the existing track as the final alignment is examined, and need for avoiding sharp kinks and dwellings is explored.|
|2.||Topographical survey||:||The topographical survey is carried out with a plane table/ compass/ theodolite, designing the horizontal curves. A line of levels is run along the centre line and cross-sections are taken.|
|3.||Soil survey||:||Samples of local soils are collected and tests like grain-size analysis, moisture-density relationships and CBR are carried out.|
|4.||Material survey||:||The source of materials for forming the embankment, pavement layers and cross-drainage structures are identified and their leads established.|
|5.||Hydrological survey||:||The sites for bridges are selected and hydrological survey to determine the discharge and HFL is carried out.|
|6.||Traffic Estimation||:||On existing roads, traffic survey is done. On new roads, the traffic likely to ply is estimated. The growth rate is determined.|
|7.||Pavement Design||:||Considering the soil strength, traffic and design life, pavement thickness is determined. Its composition is selected after exploring the ways to maximise the use of local materials.|
|8.||Drainage Plan||:||A drainage plan is made for the road giving a scheme for the effective drainage of water into natural channels, supported by levels.|
|9.||Design of cross-drainage works||:||The type of culverts, bridges and causeways is selected and design of the various elements like foundations, substructure and superstructure is done.|
|10.||Preparation of Land Plans||:||Plans showing the land holdings and the selected alignment are made to a scale of 1:8000 to 1:2000, depending upon the availability of maps. The existing village plans available with the revenue authorities are generally used.|
|11.||Preparation of road drawings||:||Alignment Plans, Longitudinal Sections and Cross-sections are prepared.|
|12.||Preparation of drawings of C.D works||:||Drawings of culverts, causeways and bridges are prepared.|
|13.||Selection of specifications||:||The specifications for various items of work are selected, keeping in view need to adopt intermediate technology.|
|14.||Estimation of quantities of items of work||:||Detailed quantities of each item of work are worked out.|
|15.||Analysis of Rates||:||The rates for each item of work are analysed.|
|16.||Estimate||:||The estimated cost is arrived.|
|17.||Preparation of DPR documents||:||The DPR documents are prepared.|
The Junior Engineer shall prepare the DPR as per the provisions of the relevant IRC Codes of Practice and bring out the document along with all data supported by necessary investigations and the maps/ drawings. It is emphasized, in this context, that the Senior Engineers of the Department shall make a reconnaissance of the proposed link, prior to the investigation and preparation of DPR. Even when the preparation of DPRs is outsourced, the Senior Engineers of the Executing Agency will do the reconnaissance.
Having prepared the DPR the Engineer concerned shall cross check that the data used in the Designs is correct and the Estimations are accordingly made.
|Volume I||:||Report and Estimate in A4 size.|
|Volume II||:||Drawings in A3 Size.|
Volume I (Report and Estimate) shall have the following contents:
Name of work, its status vis-à-vis Master Plan, Core Network, priority, terrain, geography, climatic conditions, habitations served
Obligatory points, existing tracks
Present and proposed right-of-way, Need for new land, Status of Land Acquisition
|4.||Geometric Design Standards||
Roadway width, carriageway width, shoulders, design speed, horizontal curves, vertical gradient, cross slopes etc.
Surveys carried out
|6.||Soil and Materials Survey||
Borrow Area, Quarry Charts, availability of local materials, test results
Different types of rural vehicles plying per day.
|8.||Pavement Design and Surfacing||
Type of pavement, thickness design, use of local materials, type of surfacing adopted
Data required for hydraulic design of cross-drainage works.
|10.||Design of Cross-Drainage Structures and Integration of Drainage System||
Types of culverts, submersible bridges, paved dips, High Level Bridges, and justification for selection.
Retaining walls, breast walls, check walls
Choice of technology, specifications adopted
|13.||Environmental Issues and Mitigation Measures||
Re-instatement of borrow areas, erosion control etc.
|14.||Analysis of Rates||
Rates of different items of rural road pavement construction.
Provision for contingencies, Quality Control, Supervision
Bar chart showing activities and time frame
|17.||Undertaking for Future Maintenance||
State’s commitment of funds needed for maintenance and adoption of maintenance management system.
A Detailed Project Report (DPR) is to be prepared for each proposal after collecting necessary base data. The DPR essentially should contain the following:
Population of the habitation(s) connected.
Population (Direct + Indirect) served by the proposed road.
A drawing (Not to scale) showing the nature of connection and the habitation(s) connected/ served by the proposed road.
Type and condition of the existing road/track.
It is to be ensured that the data is complete in all respects in Formats F1 to F9 which forms an integral part of the DPR and the design of Geometrics, Pavement and CD works should be strictly in accordance with the provisions of the Rural Roads Manual (RRM) (IRC : SP 20 : 2002).
The following drawings should accompany the DPR as Volume II:
Key Map, showing the State in relation to India, District in relation to State, and a district map showing all the Blocks, with the names of each Block marked.
A Block road map showing the Master Plan and the Core network and the proposed road.
An Index Map of the road showing the full road to a suitable scale, topographical features like rivers, canals, streams, railway lines, villages, Market Centres, other roads and Legend.
Plan and Longitudinal Sections of the road, showing 1 km in each sheet.
Drawings of culverts, submersible bridges, paved dips and High Level Bridges, giving General Arrangement Drawings (GAD), structural details.
Drawings of protective works like retaining walls, breast walls, check walls, drains.
Miscellaneous Drawings like kilometre stones, Traffic signs.
6.4 CHOICE OF TECHNOLOGY
Since there is readily available labour in most rural areas of the country, and Rural Road construction and maintenance can be efficiently implemented by labour-oriented or appropriate technology, the DPR should be prepared keeping this important consideration in view. Simple agricultural tractor-based equipment is very easily manufactured and serviced in the rural areas, and can produce roads of acceptable quality for the PMGSY. The use of modern highway construction equipment like large capacity Hot Mix Plants, Paver Finishers, Wet Mix Macadam Plants, Vibratory Rollers, Earthmoving and excavating equipment may not be insisted upon where it is not cost and/or time-effective.
The MoRTH Specifications for Road and Bridge Works are intended for highway facilities like National Highways and State Highways. These are not in conformity with specification prescribed in RRM. Therefore, a separate book of Rural Road Specifications has been drawn up by the IRC. The specifications in the DPR for PMGSY road works will be based on the specifications contained in the above document brought out by IRC as ‘Specifications for Rural Roads’ for MoRD in 2004 for adoption to all Rural Roads.
6.6 STANDARD NOMENCLATURE OF ITEMS OF WORK
The items of work involved in Rural Road works are not large in number and therefore, it would be advantageous if the nomenclature of these items is standardised. Adoption of information data analysis for the standardised times and rate analysis will also facilitate comparison of rates across the country. Accordingly the estimates and BOQ should be based on the standard items, and the Standard Rate analysis for Rural Roads published by the IRC as ‘Standard Data Book: Analysis of Rates for Rural Roads – 2004’.
6.7 ANALYSIS OF RATES
While preparing schedule of Rates using MoRD, Standard Data Book (SDB) for Analysis of Rates for Rural Roads the following principles should be kept in view:
The Schedule of Rates (SOR) shall be prepared by the competent authority of the State Government as per the prevalent practice of the State either at State level, Revenue Division or Circle level or District level as the case may be. States may, at their option switch over to district-wise Schedule of Rates with the help of the software made available.
The nomenclature of all the items of works will be strictly as given in “Ministry of Rural Development - Standard Data Book for Analysis of Rates for Rural Roads” September 2004 (SDB).
The coefficients given in the Standard Data Book Analysis shall be used together with the adopted basic rates for material, labour and machinery to compute the rate of the complete items of work as per Schedule of Rates.
Complete items of work include cost of labour, material, machinery and transportation/ carriage. General Conditions in the Standard Data Book provide that complete item of work includes the rate of material at source and also the carriage to site of work including loading, unloading and stacking. Various States have different practices. In some States the component of loading, carriage, unloading and stacking are added separately to the basic rate at source, while others follow the all inclusive rate particularly for items like select soil, coarse and fine aggregates, bricks, stone etc. In order that the cost of each component is easily distinguishable and verifiable that each element has been properly accounted for, it is recommended that cost of material at source and the carriage element using analysis given in Chapter 1 of SDB are shown separately in the analysis of rates.
If any item is used which is not covered in the SDB, the analysis will be approved by the competent authority under intimation to the NRRDA and STAs in the State.
The Schedule of Rates may be updated annually and updated Schedule used at the time of estimation/ technical sanction for the annual proposals under PMGSY. A copy of the Schedule of Rates may invariably be endorsed to the STAs.
The estimates shall reflect the true scope, quantum and cost of works, based on detailed surveys and investigations. The following points may be kept in view while framing the estimates:
The borrow areas must be located accurately. It is not advisable to borrow earth from the road land. Temporary earth from adjacent fields may be borrowed with the consent of the farmers. Otherwise, fallow land, and non-agricultural land, near to the project may be identified. The lead and lift involved may be accurately assessed and accounted for. The haulage method should also be identified.
The sources of gravel, sand, stone aggregates, bricks and marginal materials should be accurately identified, and the availability of the required quantity and quality of materials established. The leads involved, and the condition of roads leading to the sources shall be determined.
The rates shall be based on the State’s updated Schedule of Rates based on Standard Data Book: Analysis of Rates for Rural Roads 2004 (See para 6.8).
No provision for escalation shall be allowed.
For externally funded projects, contingencies supervision charges may be allowed as agreed upon.
Several roads in a Block or in adjacent Blocks can be combined into packages of a value of Rs 1-5 crores. The abstract of the cost shall be given in Forms F-1, F-2A and F-2B (Annexure 7.1).
The total proposal for the State shall be submitted in District wise volumes to the NRRDA.
A package will be identified by a unique number given to it. The package number shall be designated as RJ 03 07, as an example, shown below:
6.9 ENVIRONMENTAL MANAGEMENT
It is very important that the impact of road schemes on the environment be considered at the planning and design stage itself. It is also necessary that adequate safeguards are taken to prevent environmental degradation during the construction phase.
6.9.2 Selection of Alignment
Most of the Rural Roads are aligned along tracks or footpaths, which are already in existence. Utilising the existing facility to the maximum possible extent will minimise the hardships caused by land acquisition and also minimise incremental environmental impact. Ecologically sensitive areas like national parks, wildlife and bird sanctuaries, and reserve forests should be avoided. In general, drainage and hydrology should be given due consideration. An alignment, which balances the cuts and fills is not only economical, but also avoids the problems of disposal of excess material from cuts and locating fresh borrow areas. The balancing of cuts and fills should, ofcourse, not sacrifice geometric standards.
6.9.3 Borrow Areas
It is observed that in most of the Rural Roads being constructed now, the borrow areas are located just by the side of the road embankment. This may be economical to the contractor, but it is an environmental hazard, because of the following:
As such, borrow pits should not be dug close to the road embankment. Earth may be taken from the adjoining fields by obtaining consent of the farmers. Earth may also be borrowed from areas not cultivated, though this may involve some lead. The tender documents should clearly indicate the borrow areas identified, and the tender items must specify the lead and lift involved, so that the contractor knows the scope of the work and quotes accordingly. The borrow areas must be either filled up or landscaped with vegetation such that they do not present ugly scars.
In most of the Rural Roads, erosion of the slopes of the embankments, rain cuts and erosion of the earth in the shoulder are commonly observed defects. The erosion of the slopes causes the loss of the roadway width, besides leading to sedimentation of the adjoining water bodies and natural drainage channels. This must be arrested by turfing the embankment slopes and earthen shoulders. Provision must be made in the estimates for this item, wherever found essential.
6.9.5 Road Drainage
At the edges of the road land, shallow roadside drains should be provided to drain away the water from the road. These drains must have a designed longitudinal gradient, so that the water is led to a natural drainage channel. Where two roads intersect, there should be culverts to continue the drainage if the slope of the terrain demands it. If the levels permit, and the intersection is on higher ground, the side drains may have longitudinal slopes away from the high ground.
To prevent erosion of the side drains, they must have sufficient cross-section so as to promote a non-silting and non-scouring velocity. It is always preferable to turf the sides of the drain to prevent erosion, which can lead to sedimentation and reduction in carrying capacity.
Inadequate waterway across the road can cause flooding of the land upstream; such situations must be avoided.
The road construction should not adversely impact on fisheries, pond, aquatic ecology and other beneficial uses of water by the community.
6.9.6 Roadside Plantations
To improve the landscape, suitable species of trees and shrubs should be planted along the road, away from the road embankment. They should preferably be at the land boundary, so that the future encroachment of road land is avoided. The community must be encouraged to take up tree plantation activities and look after them. The choice of species should be made in consultation with the local community.
6.9.7 Roads Through Villages
When roads pass through villages, care shall be taken to ensure that there are side drains on either side to drain away the water from the road and the discharge from the abutting houses. The road level shall be sufficiently above to ensure that the road itself does not act as a drain. Provision of a concrete pavement provides a dust-proof and low maintenance road, which suffers less damage during occasional overtopping.
6.9.8 Use of Cut-Back
It is the normal tendency on the part of the contractors and the engineers to dilute the bitumen by adding diluents like kerosene. The kerosene and other diluents will ultimately find their way to water-bodies and contaminate them. The use of cut-backs should be prohibited. If liquid bitumen is needed for spraying and premix work, an emulsion should be preferred. Cut-backs shall be permitted only in extremely cold temperatures.
6.9.9 Conservation of Stone Materials
Though stone sources are abundant in India, the use of stone should be restricted to the barest minimum. Wherever possible, low cost marginal materials like soil, gravel, moorum and kankar should be used, if necessary by processing them by stabilisation.
6.9.10 Use of Flyash
In areas near to thermal power plants, flyash is available in plenty, almost at a throw-away price. Flyash should be used in rural road construction (also refer Annexure 5.4):
as an embankment fill material (for high embankments above 3m height, and with a minimum cover of ordinary soil 1000 mm thick on sides and 500mm below the bottom layer of the pavement).
as a partial replacement for cement in cement concrete pavements.
as a stabilising agent in conjunction with lime, for soil stabilisation and lime-flyash-concrete.
Since the use of fly-ash wherever possible within a radius of 100 Km of thermal plants is mandatory, the PIU shall ensure that the possibility of its use is fully investigated.
6.9.11 Historical/ Cultural/ Religious Monuments
The road alignment should not cause impact on or damages to historical, cultural and religious monuments.
6.9.12 Environmental Measures in Hill Roads
The construction of roads in hilly region disturbs the ecosystem in many ways. The main ecological problems associated with hill road construction are:
Geological disturbances and stability of slopes is a major concern in hill roads. During DPR preparation proper geological investigation need to be carried out. The rock profile and geologically critical sections in many States have been mapped based on satellite imaginary and should be made use of for carrying our detailed investigations. Slope stability analysis for retaining wall/breast walls of height greater than 5m shall be carried out as per IRC:SP-48 and incorporated in DPR.
In addition to stability analysis the alignment should be such that steep as well as heavy cuts are avoided. Rock fall can be controlled through use of geogrids or rock bolts.
Soil erosion is a consequence of high runoff on hill slopes. Construction of interceptor ditches/catch water drains to protect the road formation and hill side slope are effective in areas of high intensity rainfall and where slopes are exposed.
On side slopes in hill, immediately after cutting is complete and debris is removed, fast growing species of grass should be planted. This would prevent high velocities of runoff. Sodding and turfing, vegetation or pitching, asphalt mulch treatment, use of jute or coir netting are some of the measures of preventing erosion on hill slopes.
Sheet and gully erosion on gentler slopes can be prevented effectively through construction of check dams (maximum height 0.6m). These can be constructed using locally available material such as riprap, logs, sandbags and or straw bales. If the length of hill slopes is long multiple check dams can be provided.
Loss of tree cover
Any felling of trees during the construction of hill roads should be minimised. If some trees are unavoidably cut, additional compensatory tree plantation is required to be carried out as per Forest Department instructions.
When hill faces with vegetation cover are cut, the cut faces present a scar on the general landscape. Visual appearance should be restored through fresh vegetation cover, which may be hastened through asphalt mulch technique or jute/coir/geofabric / geogrid matting.
Waste and debris generated through construction activities can be reused and if cannot, it needs to disposed off in a manner that they do not damage water bodies and cause siltation to ponds and channels. In this respect, tipping of wastes into stream channels, water bodies, forests and vegetated slopes should be avoided. Some of the measures of waste disposal are:
Construction of gabion walls – these are constructed on valley side at ridge locations to form a trough for waste disposal. These walls can withstand large deformation without cracking and are flexible. Further due to open nature of the structures they allow free drainage of water. After filling up of the disposal site, it shall be grassed and suitably vegetated to prevent erosion of the disposed soil.
Silt fencing – it is a sediment barrier provided to prevent sediment carried by sheet flow from leaving the site and entering to natural drainage or any other water body located near the construction site.
Bally benching – These are provided in order to arrest the shallow movement of top mantle slide mass at the construction location.
If the wastes generated during construction cannot be reused, the following precautions should be adopted
In case of bituminous wastes, dumping will be carried out over a 60mm thick layer of rammed clay so as to eliminate any chances of leaching.
In case of filling of low lying areas with wastes, it needs to be ensured that the level is matched with the surrounding areas. In this case, care should be taken that these low laying areas are not used for rain water storage.
The excavating of material from quarry area should be done with minimum adverse impacts on environment. It should be ensured that adequate drainage system has been provided to prevent the flooding of the excavated area. At the stock piling locations, sediment barriers (brush barriers) shall be constructed to prevent the erosion of excavated material during runoff.
Water for Construction.
In water scarce regions and in winter season when water availability is not sufficient, the various construction activities need to be rescheduled to reduce the drawl of water from community sources. Various modern techniques like Water harvesting/Ground water recharging are needed to be explored to avoid water extraction from the community sources.
6.9.13 Measures Needed in Desert Roads
The construction of roads in arid region disturbs the ecosystem in many ways. The main ecological problems associated with desert road construction are:
In case of roads in arid areas, the embankment made up of silty and cohesion less sandy soils are subjected to erosion due to high wind velocities. Also, when the slopes are steep (more than 20 degrees), the erosion of embankment is more predominant. As a result there is reduction in road formation width (erosion of shoulders/berms). Moreover, the sand gets deposited over or near the road surface, which is not desirable. In order to avoid the deposit of sand, hardy variety of shrubs and plants are planted at appropriate distance from the formation. There should be a clear gap between the roadway and shrubs to allow the wind to pick up its velocity and carry along with it any sand that is deposited.
Desert roads passing through shifting sand dunes require special design considerations. Some of the proven techniques are:
Avoidance of partial cut and partial fill sections:- Partial cut and partial fill sections should be avoided as they will provide loose sand to be carried away by high wind velocities which in turn will be deposited over the road and nearby areas.
Avoidance of high embankments:- High embankment should be avoided in desert areas as they are subjected to more erosion in the absence of vegetative cover.
Top soils with humus, wherever encountered while opening up the site for construction, shall be stripped, stockpiled and used for restoration of borrow areas to maintain its fertility.
Water for construction-
In water scarce regions construction activities need to be rescheduled to reduce drawl of water from community sources to a minimum. Assessment of water requirement for each stage should be made. Earthwork for embankment can be carried out just before monsoon so that subsequent works of granular sub-base and WBM can be carried out during monsoon when water is readily available.
Water harvesting structure (water tanks for collection of rain/stream water) may be constructed where feasible to provide water for construction.
6.9.14 Environmental Considerations during Maintenance
The following guidelines may be noted:
For making up the eroded slopes and shoulders, earth should not be borrowed from roadside land. This leads to formation of deep side channels, endangering the stability of the road embankment and creating pools of stagnant water where mosquitoes breeding can take place. Earth should be borrowed from nearby fields after obtaining consent of the farmers.
The turf on embankment slopes, shoulders and drainage ditches must be trimmed periodically.
The turf on embankment slopes, shoulders and drainage ditches must be trimmed periodically.
6.10 ECONOMIC ANALYSIS
While providing new links to unconnected habitations is a social responsibility, the investments on upgradation of existing roads should result in economic benefits. Proposals for upgradation should be subjected to economic analysis. The specifications for upgradation and maintenance interventions should be so selected that the IRR is at least 12 percent. The benefits that may be considered for the analysis may include (i) agricultural producer surplus (ii) savings in vehicle operating costs and (iii) savings in travel time of passengers.
6.11 USE OF CONSULTANTS FOR PREPARATION OF DPR
The task of survey, investigations, design and preparation of DPRs is laborious and requires skill and experience. Since PMGSY is a time-bound programme, State Governments need to build up capacity to prepare DPRs of acceptable quality. For this purpose, they may outsource this service where adequate in-house capacity is not available, to Consultants with adequate expertise and capacity. This may be done after inviting expression of interest and short-listing prospective consultants meeting the requirements including previous experience of preparing DPRs of road works equal to at least 50% of the value of the proposed DPRs.
The work of design Consultants should be periodically evaluated by assessing:
Operations Manual for Rural Roads The Consultants whose work has not been wholly satisfactory should not be awarded further consultancies.