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Street Engineering Equipment: Slopes, Pavements, Drainage and Utility Networks

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The key engineering characteristics of streets are their longitudinal and transverse gradients, together with the pavement structures of the carriageways and footways.

Sidewalk
Footway surfacing is an important engineering characteristic of streets

To organise the drainage of rainwater from street surfaces correctly, the streets must be given gradients of a specific magnitude. These gradients are determined according to the street category and the type of road surface.

The "most convenient" surfaces for vehicle traffic are smooth asphalt and cement-concrete pavements. Such surface types have a lower degree of roughness, so rainwater runs off them more easily and quickly.

The longitudinal gradient of footways should not exceed 8%. Where the gradient is steeper, stairs are built into the footway. The value of the transverse gradient depends on the type of road surface and on the magnitude of the longitudinal gradient. For the carriageway it is set within the following ranges:

  • carriageway — from 1 to 2%,
  • footways — 1.5 to 2%,
  • planting strips — 0.5 to 1.5%.

Water runs off along the pavement and follows the transverse gradient. It collects in open gutters, then is directed along the longitudinal gradient parallel to the street axis, and through catch basins installed every 150–300 m it enters the closed storm drainage network.

Beneath the carriageway, footways and landscaped strips run the underground utilities: pipelines for water, heat and gas supply; high- and low-voltage cables, as well as low-current lines such as telephone, telegraph and others; and ducts for the joint or separate laying of pipelines and cables.

Sewerage is of great importance, as it is the means by which waste water is discharged (Fig. 3).

Street engineering equipment
Layout schemes for underground networks beneath arterial streets: a — with separate laying; b — in a common trench; c — in a duct

To operate all of these networks, special facilities are built:

  • water intake stations,
  • gas regulating stations (GRS),
  • step-down substations and combined heat and power plants (CHP),
  • automatic telephone exchanges (ATE),
  • transformer substations (TS) and others.

All underground networks are divided into the following categories: urban, arterial, distributing street networks, microdistrict internal networks, networks serving the microdistrict, and building service connections and inlets.

Frequently Asked Questions

What is the maximum longitudinal slope for sidewalks?
The longitudinal slope of sidewalks should not exceed 8%. When slopes are steeper than this, stairs are built on the sidewalks to allow safe pedestrian movement.
What are the recommended transverse slopes for streets?
Transverse slopes are set at 1-2% for roadways, 1.5-2% for sidewalks, and 0.5-1.5% for planting strips. The exact value depends on the pavement type and the longitudinal slope size.
How is rainwater drained from street surfaces?
Water flows across pavements via the transverse slope into open gutters, then moves parallel to the street axis along the longitudinal slope. It enters closed drainage networks through water intake wells placed every 150-300 meters.
What underground utilities are placed beneath streets?
Beneath roadways, sidewalks, and green strips are water, heat, and gas supply pipelines; high and low voltage cables; weak current cables like telephone and telegraph; and collectors for joint or separate placement of pipelines and cables.
Which pavement types are best for vehicle traffic?
Smooth asphalt and cement-concrete pavements are the most convenient for vehicle movement. They have lower surface roughness, allowing rainwater to drain more easily and quickly from the road surface.
What special structures support underground utility networks?
Special structures include water intake stations, gas regulating points (GRP), step-down substations and thermal power plants, automatic telephone stations (ATS), and transformer substations (TP) for network operation and maintenance.

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