Guidelines on Accommodation of Utility Services on Roads in Urban Areas (Second Revision)

IRC 98 (Second Revision) - Scope Summary

Scope (Clause 2) covers guidelines for accommodation of utility services on urban roads, including:

• Planning and coordination for utility line placement.
• Specifications for depth, location, and space for utility lines.
• Design criteria for utility ducts and crossings on roads and bridges.
• Protocols for road opening, trenching, and HDD (Horizontal Directional Drilling).
• Restoration and maintenance requirements post-utility installation.
• Application procedures for permits (Appendix-I & II).
• Use of Controlled Low Strength Material (Appendix-III).

Key Specifications & Protocols

• Depth of laying service lines: As per Clause 3.3, utility lines must be laid at adequate depth to avoid damage by traffic or maintenance.
• Road Opening: Use trenching or HDD with strict adherence to restoration protocols (Clause 4).
• Trenching Pit Size: Minimum 1200 mm x 1500 mm.
• Restoration: Use hot mix or premix asphalt; joints sealed with hot bitumen; vehicular traffic prohibited for 7 days on concrete reinstatement.
• Footpath width ≤ 1.4 m: Entire width must be restored.
• Maintenance period: 1 year, during which defects must be rectified by the applicant.

Application Forms

• Appendix-I: Application for trenching/HDD openings.
• Appendix-II: Utility permit application for urban road right of way.

Summary Table: Road Opening & Restoration

flowchart LR
    A[Planning Utility Lines] --> B[Depth & Location Specification]
    B --> C[Permit Application]
    C --> D[Road Opening (Trenching/HDD)]
    D --> E[Utility Installation]
   

Classification of Utility Services & Space Requirements (IRC 98)

1. Classification by Road Category (Clause 3.4.1 & IRC:69):

2. Utility Services Accommodation:

• Utility lines should be placed in earmarked service corridors alongside roads.
• Space varies by type, size, and number of utility lines.
• Major roads require larger service corridors than minor roads.
• Typically, 5 m width on either side of the road is adequate for services.
• If space is limited, utilities should be placed in common utility ducts at the extreme ends of the right of way.

3. Hierarchy Principle:

• Main utility lines run along major roads.
• Minor utility lines run along minor roads.

flowchart LR
    A[Road Category] --> B[Land Width]
    B --> C[Space for Utility Services]
    C --> D[Major Roads: Larger Space]
    C --> E[Minor Roads: Smaller Space]
    C --> F[Common Utility Duct if Space Limited]

This classification ensures organized, safe, and accessible utility service placement respecting road hierarchy and urban land width standards.

IRC 98 - Clause 3.4: Location and Space for Services

Key Specifications:

• Land Width for Urban Roads (IRC: 69):

• Space for Utility Services:
  • Generally, 5 m width on either side of the road is adequate for utility lines.
  • Larger roads (arterial, expressways) require more space due to larger and more numerous service lines.
  • Utility lines should be placed in earmarked service corridors; if unavailable, use common utility ducts at extreme ends of right of way.
  • Placement depends on:
    • Road class
    • Land width available
    • Size and type of utility lines

Summary:

• Utility services follow the road hierarchy: major roads → larger utility space.
• Use common ducts if space acquisition is not possible.
• Plan service lines considering road function and land availability.

flowchart LR
    A[Road Classification] --> B[Land Width as per IRC:69]
    B --> C[Space for Utility Lines]
    C --> D{Is earmarked space available?}
    D -- Yes --> E[Place utility lines in service corridor]
    D -- No --> F[Use common utility ducts at ROW ends]

This ensures safe, accessible, and organized utility service provision along roads.

IRC 98: General Considerations for Utility Lines

Key Points from IRC 98 (General Considerations)

• Planning (Clause 3.1): Proper planning is essential for utility line layout to avoid conflicts with road infrastructure.

• Special Locational Requirements (Clause 3.2):

  • Utility lines must be located to minimize interference with road structure and maintenance.
  • Maintain adequate depth and horizontal clearance from road edges and other utilities.
  • Use common utility ducts to consolidate lines and reduce road openings.

• Depth of Laying (Clause 3.3):

  • Minimum depth depends on road type and traffic loading.
  • Typically, 0.6 to 1.0 m below road surface for water/gas lines.

• Location and Space for Services (Clause 3.4):

  • Utility lines should be placed in designated corridors or margins.
  • Maintain minimum spacing between different utilities to allow maintenance.

• Road Opening Protocol (Clause 4):

  • Permits required before trenching/opening.
  • Use controlled low strength material (CLSM) for backfilling (Appendix-III).

Typical Specifications Summary

Permit Application Essentials (Appendix-I)

• Agency details, location, type of opening (trenching/HDD)
• Confirmation of adherence to specifications and indemnity
• Area and fee calculation based on sq. meters of opening

flowchart LR
    A[Planning Utility Lines] --> B[Maintain Depth & Clearance]
    B --> C[Use Common Utility Ducts]
    C --> D[Apply for Road Opening Permit]
    D --> E[Execute Trenching/HDD]
    E --> F[Backfill with CLSM]
    F --> G[Maintenance & Indemnity Period]

Summary: IRC 98 emphasizes careful planning, minimum depth and clearance,

IRC: 98 – Characteristics of Utility Lines

Key Considerations (Clauses 3.2 & 3.8)

• Clause 3.2: Utility lines must be located to avoid interference with other services and ensure safety.

  • Maintain minimum clearances from road edges, structures, and other utilities.
  • Account for future expansion and maintenance access.
  • Follow local regulations for underground and overhead lines.

• Clause 3.8: Utility line drawings should clearly show:

  • Exact location, depth, and alignment.
  • Type of utility (electric, water, gas, telecom).
  • Crossings and separations from other utilities.
  • Details of supports, poles, or trenches.

Typical Minimum Clearances (IRC 98 Guidelines)

Summary Diagram

graph LR
A[Road Edge] --> B{Utility Lines}
B --> C[Electric Lines (Overhead & Underground)]
B --> D[Water & Gas Pipes (Underground)]
B --> E[Telephone Lines (Overhead & Underground)]
C -- Clearance --> F[5.5m - 7.5m Overhead]
D -- Depth --> G[0.9m - 1.2m Underground]
E -- Clearance/Depth --> H[3.0m Overhead / 0.6m Underground]

Ensure all utility lines comply with IRC 98 for safety, maintenance, and coordination with road infrastructure.

Depth of Laying Service Lines along Roads (IRC 98 - Clause 3.3.3)

Minimum Cover:

• For service lines crossing minor roads without encasement, minimum cover = 1.2 m (Clause 1.2).
• Embed pipes on granular bedding free of stones.
• Backfill in two stages: up to pipe top, then up to subgrade.
• Provide sand cushion and brick lining for protection and identification.

Minimum Separation Distances:

flowchart LR
    A[Service Line] --> B[Trunk Sewer (>1.5 m)]
    A --> C[Water Supply]
    C --> C1[Service line (0.6-1 m)]
    C --> C2[Trunk line (1-6 m)]
    A --> D[Electric Cable]
    D --> D1[LT (0.6-1 m)]
    D --> D2[HT (1.5-2 m)]
    A --> E[Telecommunication]
    E --> E1[Direct (0.6-1 m)]
    E --> E2[Duct (1-2 m)]
    A --> F[Gas Mains (2-3 m)]

Protection and Design of Manholes and Chambers as per IRC 98

Key Specifications & Design Points:

• Manhole Covers:

  • Should be flush with road surface; no protrusion.
  • Covers must be maintained at road level during resurfacing.
  • Strengthened by M40 grade interlocking paver blocks or concrete around the manhole to absorb vehicular impact (Fig. 2).

• Water Valve Chambers:

  • Covered with RCC or BS slabs.
  • To avoid slab damage from traffic, fill chamber with sand cushion.
  • Access via PVC pipe for valve operation (Fig. 3).

Design Considerations:

• Manholes and chambers must be durable and strong to withstand traffic loads.
• Use M40 grade concrete for surrounding protection.
• Seal annular spaces to prevent ingress of water, gas, or soil.
• Provide nylon draw strings (6 mm dia) inside ducts for cable pulling.
• Concrete surround for ducts: Grade 30/20.

Typical Dimensions (mm):

Structural Design Summary:

• Treat ducts and chambers as normal structural elements.
• Design for future expansion and durability.
• RCC cover slabs for chambers should be designed for vehicle load impact.
• Manhole surrounds should prevent damage from repeated vehicular impact.

flowchart TD
    A[Manhole/Chamber] --> B[Cover slab (RCC/BS slab)]
    B --> C[Surround with M40 concrete or interlocking pavers]
    A --> D[Seal annular spaces]
    A --> E[Sand filling in valve chambers]
    E --> F[Access via PVC pipe]

References: IRC 98 Clauses 3.4.2 (iv, v), 3.5.3; Figures 2 & 3; Photo-3.

IRC 98 Key Points: Accommodation of Utility Lines Across Roads and Bridges

1. Utility Lines Across Roads (Clause 3.6)

• Positioning: Utility lines should preferably be located outside the road right-of-way.
• Crossing Angle: Should cross at right angles (90°) to minimize trench length.
• Depth of Cover: Minimum cover over utility lines under carriageway:
  • Roads: 0.75 m to 1.0 m (depending on traffic load)
• Protection: Use protective sleeves or encasements to avoid damage during road works.

2. Utility Lines Across Bridges (Clause 3.7)

• Attachment: Utility lines should be attached to the bridge superstructure or substructure without affecting structural integrity.
• Load Consideration: Additional loads due to utility lines must be considered in design.
• Clearances: Maintain adequate clearance from structural members for inspection and maintenance.
• Corrosion Protection: Provide suitable corrosion protection for utility line supports.

Summary Table:

flowchart TD
    A[Utility Lines] --> B[Across Roads]
    B --> C[Prefer outside ROW]
    B --> D[Cross at 90°]
    B --> E[Min cover 0.75-1.0 m]
    B --> F[Protective sleeves]

    A --> G[Across Bridges]
    G --> H[Attach to structure]
    G --> I[Consider additional load]
    G --> J[Maintain clearances]
    G --> K[Corrosion protection]

Note: Always refer to the latest IRC guidelines and local amendments for project-specific requirements.

IRC 98: Installation Methods & Specifications for Casing Pipes

Key Specifications:

• Material: Steel, cast-iron, or RCC (NP4 grade).
• Strength: At least equal to normal cross-drainage structures considering overfill.
• Length: Extend from drain to drain (cuts) or toe to toe of slope (fills).
• Cover: Minimum 1.2 m below road level and at least 0.3 m below drain invert.
• Sealing: Ends must be sealed to prevent drainage through annular space.
• Steel casing: Should be leak-proof, jointless if possible; anticorrosive paint mandatory.
• Size: Large enough for easy withdrawal of carrier pipes/cables.

Installation Methods:

• Preferred: Boring through road embankment.
• Alternate (exceptional): Trenching with bedding on 0.15–0.30 m thick granular layer free of rock pieces.
• Backfilling: Two-stage—first up to pipe top, then up to subgrade.
• Precautions: Follow pipe culvert construction procedures.

Bedding & Backfill:

Typical Cross-Section (Fig. 3.10 Summary):

graph TD
  RoadSurface[Road Surface]
  Subgrade[Subgrade]
  Backfill2[Backfill (Stage 2)]
  Backfill1[Backfill (Stage 1)]
  Bedding[Bedding (0.15-0.30 m granular)]
  CasingPipe[Casing Pipe]
  DrainInvert[Drain Invert]

  RoadSurface --> Subgrade
  Subgrade --> Backfill2
  Backfill2 --> Backfill1
  Backfill1 --> Bedding
  Bedding --> CasingPipe
  CasingPipe --> DrainInvert

Summary: Use NP4 or equivalent casing pipe, ensure proper cover and sealing, prefer boring installation, and backfill in two stages on granular bedding for durability and structural integrity

IRC 98 - Accommodation of Utility Lines on Bridge Structures (Clause 3.7)

Key Specifications:

• Utility lines (water, gas, electricity, telecom) should be accommodated without compromising structural safety.
• Utility supports must be independent or designed to transfer loads safely to the bridge.
• Avoid inducing additional moments or forces in the main structural elements.
• Provide adequate clearance and protection against mechanical damage and corrosion.

Important Guidelines:

• Load Consideration: Include utility line weight and maintenance loads in design load combinations.
• Clearance: Maintain minimum vertical clearance as per IRC 6 or relevant utility codes.
• Support Design: Utility supports may be cantilever brackets or hangers fixed to non-critical parts.
• Access: Ensure safe access for maintenance without affecting traffic or structure.

Typical Load Addition Formula:

[ P_u = W_u + F_m ]

• (P_u): Total utility load on structure
• (W_u): Weight of utility line and supports
• (F_m): Maintenance or dynamic load factor (usually 1.2 to 1.5 times (W_u))

Table: Minimum Clearances (Indicative)

flowchart TD
    A[Bridge Structure] --> B[Utility Support]
    B --> C[Utility Line]
    B --> D[Load Transfer to Bridge]
    C --> E[Maintenance Access]

Note: Refer IRC 98 Clause 3.7 and IRC 6 for detailed clearance and load requirements.

IRC 98 - Inventory and Documentation of Utility Networks

Key Specifications (Clause 3.8 & 3.8.2)

• Utility Drawings Submission:

  • All utility service providers must submit complete network drawings (both hard and soft copies) to the road authority.
  • Drawings must show exact locations, depths, and alignments of underground utility lines.

• Purpose:

  • To ensure proper coordination and avoid damage during road works.
  • Facilitate maintenance and future planning.

Recommended Documentation Details

Best Practice:

• Maintain a centralized GIS-based database for easy access and updates.
• Update drawings after any modifications or repairs.

flowchart LR
    A[Utility Service Providers] --> B[Submit Drawings (Hard & Soft)]
    B --> C[Road Authority]
    C --> D[Centralized GIS Database]
    D --> E[Maintenance & Planning]

This ensures safe, coordinated, and efficient management of utility networks under roads per IRC 98 guidelines.

IRC 98 - Coordination Among Utility Agencies

Key Points from Clause 3.9 (Co-ordination) and Related Sections:

• Objective:
  Ensure uniform planning, installation, and maintenance of utility services within urban road rights-of-way to minimize conflicts and traffic disruption.

• Coordination Guidelines:

  • Mutual Planning: Utility agencies and road authorities must collaborate early in the project.
  • Shared Utility Ducts: Encourage common utility ducts to reduce repeated road openings.
  • Scheduling: Coordinate timing of trenching and reinstatement to minimize traffic impact.
  • Information Sharing: Maintain updated drawings and records of utility line locations (Clause 3.8).
  • Permits: Use standardized application forms (Appendix I & II) for road openings and utility permits.
  • Depth & Location: Follow minimum depth and spacing criteria (Clause 3.3 & 3.4) to avoid conflicts.

Typical Coordination Workflow:

flowchart LR
    A[Utility Agency Proposal] --> B[Joint Planning Meeting]
    B --> C[Design Approval by Road Authority]
    C --> D[Permit Application Submission]
    D --> E[Scheduling & Execution]
    E --> F[Record Drawings & Reinstatement]

Summary Table: Coordination Responsibilities

This coordination ensures safe, efficient utility service installation with minimal road disruption per IRC 98 guidelines.

IRC 98: Road Opening Protocol & Precautions

Key Points from Clause 4.4 & Appendix-I:

• Application Format: Appendix-I provides a detailed application form for trenching/HDD openings including agency details, location, surface type, and indemnity clause.
• Fee: Based on square meters of opening reinstated, decided by Road Authority.
• Permit Validity: Includes opening and closing dates; HDD allowed mainly at night with restoration in 48 hours.
• Coordination: HDD applications shared among agencies to avoid repeated openings within one year.
• Barricading: As per Fig.18 and Photos 12-13, including door for entry/exit, contact info displayed.
• Restrictions: No permission during monsoon except emergencies; care to prevent earth slippage and damage to adjacent structures.

Precautions (Clause 5):

• Proper barricading and signage with contact details.
• Restoration as per IRC specifications.
• Third-party certification for reinstatement.
• Penalties for unauthorized openings (Clause 3.9.5).

Summary Table: Road Opening Protocol

flowchart TD
    A[Agency applies using Appendix-I] --> B[Road Authority reviews]
    B --> C{Permit granted?}
    C -- Yes --> D[Work allowed (HDD at night)]
    D --> E[Restoration within 48 hrs]
    E --> F[Third-party certification]
    C -- No --> G[Application rejected]
    F --> H[Road Authority monitors & penalizes if needed]

This ensures safe, coordinated, and minimal disruption road openings compliant with IRC 98.

IRC 98 Key Specifications & Protocols for Urban Road Opening by Trenching/HDD

Application & Permissions

• Application Form: Appendix-I (Urban Roads, Footpaths by Trenching/HDD)
• Permit Validity: Specific dates only; no blanket permission.
• Joint Site Visit: Mandatory before application submission.
• Emergency Work: Restore within 24 hours; notify Road Authority.

Trenching/HDD Specifications

• Footpath < 1.4 m wide: Restore full width.
• HDD Pit Size: 1200 mm × 1500 mm.
• Cutting: Only with road-cutting saw; square, rectangular, or trapezoidal shapes.
• Refilling: Within 48 hours using self-compacting material; layers max 150 mm thick.
• Surface Restoration: Use premix emulsion or hot mix; compact with rollers; flush finish.
• Joints: Seal asphalt/macadam joints vertically & horizontally with hot bitumen.
• Concrete Footpath at Driveways: 150 mm thick with welded mesh reinforcement.
• No manual compaction allowed.
• No excavated material as filler.

Safety & Maintenance

• Barricading: Display agency name, contact; follow sample barricade (Fig. 18).
• Traffic: Prohibit vehicular traffic on concrete reinstatement for 7 days.
• Maintenance Period: 1 year; defects to be rectified by applicant or charged.

Fees & Coordination

• Fee: Based on reinstated area (sq. meter).
• Coordination: HDD applications shared among agencies to minimize openings.
• Monsoon: No permission except emergency repairs.

Summary Table: HDD Pit & Restoration

flowchart TD
    A[Application Submission] --> B[Joint Site Visit]
    B --> C[Permission Granted]
    C --> D[Cutting &

Key Specifications & Procedures for Utility Permit on Urban Road Right of Way (IRC 98):

Application & Documentation

• Submit detailed application (Appendix-II format) specifying:
  • Location (road section, side)
  • Type of underground construction (conduit, casing, pipe)
  • Size, depth, voltage, number & size of conductors
  • Installation method (Open trench, HDD, DBC)
  • Tree clearing extent & schedule

Trenching / HDD Specifications (Clause 1.4 & Appendix-I)

• Footpath ≤ 1.4 m width: restore entire width.
• HDD pit size: 1200 mm × 1500 mm.
• Cutting shape: square, rectangular, or trapezoidal only.
• No manual cutting/open trenching allowed without permission.
• Excavated material must be removed beyond urban limits.
• Use road-cutting saw for straight edges.
• No excavated material as filler; refill with quarry dust/coarse sand in 15 cm layers, compacted.
• Surface reinstatement: hot mix or premix emulsion, compacted by rollers.
• Asphalt/macadam joints sealed with hot bitumen.
• Concrete reinstatement: min. 150 mm thickness on vehicular driveway crossings, reinforced with weld mesh.
• Vehicular traffic prohibited on concrete reinstatement for 7 days.

Safety & Maintenance

• Barricading with agency name & contact.
• Use GPR to detect existing utilities.
• Maintenance period: 1 year; applicant responsible for defect rectification.
• Emergency openings: restore within 24 hours.

Fees & Permissions

• Fees based on reinstatement area (sq. meters).
• Permission valid only for specified dates; no blanket permits.
• Joint site visit before application submission.

Summary Table: HDD Pit & Restoration

flowchart TD
    A[Submit Application] --> B[Joint Site Visit]
    B -->