Engineering Survey Services — Cadreatech
Infrastructure & Route Survey Services in Kenya
Longitudinal profiles, cross-sections, and full corridor mapping for roads, pipelines, sewer lines, drainage channels, and power line routes across Kenya. The instrument-verified vertical alignment data your design team needs to engineer infrastructure that performs — from county road upgrades to large-scale estate reticulation networks.
Understanding the service
What Is an Infrastructure Route Survey?
An infrastructure or route survey is a systematic, precision field measurement exercise conducted along a defined linear corridor — a proposed or existing road, pipeline, drainage channel, sewer line, power line route, or any other linear infrastructure alignment. Unlike a general topographic survey that maps an entire site area, a route survey focuses its measurement intensity on the design corridor and its immediate influence zone.
The defining output of a route survey is the longitudinal section — sometimes called the long-section or L-section — a vertical profile of the existing ground along the corridor centreline, plotted against distance (chainage) from the start of the route. This profile shows the engineer exactly what the ground is doing along the route — where it rises and falls, where structures exist, and what the terrain challenges are — so that the design vertical alignment can be set with full knowledge of actual ground conditions.
Alongside the longitudinal section, cross-sections are measured at right angles to the centreline at regular chainage intervals. Cross-sections show the ground profile across the full corridor width — the width of potential cut slopes, fill embankments, or drainage side channels — providing the additional dimension needed for earthwork volume calculations and formation width design.
Together, the longitudinal section and cross-sections give the design engineer a complete 3D picture of the corridor that can be modelled in Civil 3D, from which all design decisions flow: vertical alignment, earthwork quantities, pipe gradients, embankment dimensions, retaining structure locations, and culvert positions.
Why route surveys are essential before infrastructure design in Kenya
Kenya's infrastructure design environment often pressures project teams to begin design before survey data is available — driven by procurement timelines, client pressure, or the assumption that "we know the area." This is a false economy. Every major cost overrun and design revision on infrastructure projects in Kenya can be traced back to a design assumption that conflicted with the actual ground conditions.
Consider a county road upgrade where the engineer assumes an average formation level based on the existing road surface. Without a proper longitudinal survey, the design doesn't account for a 1.5m deep dip at a seasonal stream crossing that requires either a culvert upgrade or a costly embankment. That single omission — discoverable by a one-day route survey — can add KES 2–5 million to the construction cost when discovered during construction.
Survey stages in infrastructure project development
Route surveys are not just for detailed design — they have a role at every stage of an infrastructure project's development:
- Feasibility stage — reconnaissance-level survey at 50m chainages comparing alternative route options for earthwork cost and terrain difficulty
- Preliminary design — survey at 25m chainages with cross-sections to develop the design concept and generate indicative cost estimates
- Detailed design — full survey at 20m or closer, with comprehensive structure inventory, utility crossing record, and detailed cross-sections for BOQ preparation
- Construction — setting out from design chainage and level data, and as-built survey at completion
When you need a route survey
- Before designing a new road or road upgrade — to establish the existing ground profile for vertical alignment design
- For pipeline design — to determine pipe gradients and invert levels at valves and tie-in points
- Before designing a drainage channel, storm drain, or open stormwater channel
- For sewer design — to verify gravity flow is achievable along the proposed route and set manhole invert levels
- At feasibility stage — to compare alternative route alignments for earthwork cost and constructability
- For KeNHA, KURA, or KeRRA road project documentation at preliminary and detailed design stages
- Before applying for wayleave or right-of-way for pipeline or utility corridors
- For county government infrastructure projects requiring design drawings for tender
- Before preparing BOQ earthworks sections for infrastructure contracts
- For estate internal road and service reticulation design
Survey specification by project stage
| Stage | Chainage | Cross-section width |
|---|---|---|
| Feasibility | 50m | 10m each side |
| Preliminary design | 25m | 20–25m each side |
| Detailed design | 20m | 30–40m each side |
| Urban detailed | 10–15m | 15–20m each side |
Plus additional spot levels at all break points, structures, and utility crossings regardless of standard interval.
Infrastructure types covered
Infrastructure We Survey in Kenya
Our route survey service covers all linear infrastructure types common in Kenya's civil engineering sector — from a 200m estate access road to a 50km regional pipeline corridor.
Roads & Highways
Road centreline profiling from feasibility through detailed design — chainage establishment, horizontal alignment survey, vertical profile, cross-sections, existing pavement condition data for rehabilitation, and road furniture inventory. Compatible with KeNHA Road Design Manual, KURA Urban Road Design Guidelines, and KeRRA Rural Road Design Manual. We have surveyed county roads, urban arterials, estate access roads, and industrial access routes across Kenya.
Client types: county governments, KeNHA-contracted consultants, private developers, estate management
Sewer & Drainage Lines
Longitudinal survey along proposed sewer and surface water drainage routes — capturing existing ground levels at the design chainage, manhole positions and inverts on crossing networks, and outfall conditions at discharge points. Used to confirm that gravity drainage is achievable and to set the pipe gradient design. Sewer surveys include invert level records on existing manholes along the route where they affect design decisions.
Client types: Nairobi City Water, county governments, estate developers, NWSC-funded projects
Water Mains & Pipelines
Route survey for water supply mains, petroleum pipelines, and industrial process pipelines — capturing ground levels for hydraulic grade line design, crossing structure positions, utility conflicts, and wayleave boundary positions. For petroleum pipelines, we coordinate with KEBS and EPRA survey requirements. For water mains, output is formatted for WaterCAD or EPANET hydraulic model input.
Client types: water utilities, petroleum companies, irrigation project consultants
Power Line Routes
Survey of proposed transmission and distribution power line corridors — capturing the ground profile for tower height and conductor sag calculations, span profiles at major crossing points, and wayleave boundary positions. For KETRACO and KPLC corridor surveys, we work to the required accuracy classes and produce output formatted for PLSCADD or PLS-TOWER structural design software.
Client types: KETRACO, KPLC, independent power producers, EPC contractors
Open Drainage Channels
Survey of existing and proposed open drainage channels — channel cross-sections at regular intervals, bed levels, bank heights, connecting culvert positions, and longitudinal gradient from headworks to outfall. Used for hydraulic capacity design, flood level analysis, and Kenya Roads Board drainage channel rehabilitation projects. Channel surveys include condition assessment of bed lining, bank protection, and headwalls.
Client types: Kenya Roads Board, county public works, flood management consultants
Estate Internal Roads & Services
Route surveys for internal road networks, sewer reticulation, and water supply distribution within residential and commercial estate developments. Estate route surveys are often combined with topographic survey of the full estate area — the route survey providing detailed corridor data and the topo survey providing the wider site context for master planning and drainage design.
Client types: estate developers, housing cooperatives, residential project managers
What you receive
Route Survey Deliverables from Cadreatech
All route survey deliverables are produced in formats directly compatible with the design software and documentation requirements of your road, drainage, or pipeline design engineer.
01 — KEY OUTPUT
Longitudinal Section (PDF / DWG)
Vertical profile of existing ground along the route centreline — plotted at standard scales (1:2000H / 1:200V for roads, adjusted for other infrastructure types) with chainage, reduced levels, and gradient annotations
02
Cross-Section Drawings (PDF / DWG)
Existing ground cross-sections plotted at every chainage station — showing the transverse ground profile across the full corridor width for earthwork volume calculation and embankment design
03
Chainage & Level Schedule (CSV)
Tabulated centreline coordinates and ground levels at every chainage point — importable into Civil 3D, 12d, WaterCAD, or design software for direct use in design calculations
04
Horizontal Alignment Plan (DWG / PDF)
Plan view of the surveyed centreline, existing features, structures, utilities, vegetation, and boundaries — for alignment design and wayleave documentation
05
Civil 3D Corridor Model (DWG)
Full corridor model — existing surface, horizontal alignment, and cross-sections integrated in Civil 3D for design engineer use, including earthwork volume calculation from the corridor model
06
Structure & Culvert Schedule
Inventory of all culverts, manholes, bridges, and drainage structures along the corridor — positions, sizes, materials, invert levels, headwall conditions, and hydraulic capacity notes
07
Utility Crossing Record
Documented positions of all utility crossings along the route — water mains, power cables, telecoms, drainage — with surface indicator positions for protection or diversion planning
08
Survey Report (PDF)
Written report covering methodology, equipment, accuracy statement, coordinate system, control network, corridor findings, and any survey constraints encountered
Standards compliance
Kenyan Infrastructure Design Standards We Work To
Cadreatech route surveys are designed to produce data compatible with Kenya's official infrastructure design standards — so the survey output integrates directly into the design process without reformatting or reprocessing.
| Infrastructure Type | Applicable Standard / Manual | Survey Compatibility |
|---|---|---|
| National trunk roads | KeNHA Road Design Manual (2012) | Cross-section widths, chainage intervals, and drawing scales formatted to KeNHA requirements. Mass haul analysis included for earthworks. |
| Urban roads | KURA Urban Road Design Guidelines | Tighter chainage intervals for urban complexity. Utility crossing records formatted for Nairobi City County requirements. |
| Rural access roads | KeRRA Design and Construction Manual | Simplified cross-section templates and formation widths per KeRRA manual. Output formatted for low-volume road design. |
| County roads | County-specific standards (varies) | We confirm county-specific requirements at scoping stage and format drawings accordingly. |
| Drainage design | KeNHA Road Design Manual Part 2 | Catchment areas, culvert hydraulic data, and channel cross-sections formatted for Rational Method calculations per Part 2. |
| Water supply pipelines | WASREB technical standards | Route survey data formatted for hydraulic grade line design and WASREB project approval submissions. |
Step by step
How We Deliver an Infrastructure Route Survey
Scoping & Specification
Agree route length, chainage interval, cross-section width, required deliverable formats, and design standard with the client and lead design consultant before mobilisation
Route Reconnaissance
Pre-survey walk of the full corridor to identify terrain challenges, access constraints, vegetation, and control point locations — producing a reconnaissance report before full survey mobilisation
Benchmark Network
Vertical benchmarks established along the route at intervals appropriate for the route length — typically every 500m to 1km — for accurate level transfer throughout the survey
Horizontal Alignment Survey
Centreline established using RTK GNSS and total station — chainage pegs set at every standard interval for the full route length
Longitudinal Levelling
Ground levels taken at each chainage peg along the centreline, plus intermediate levels at all break points where gradient changes between standard chainage stations
Cross-Section Survey
Cross-sections measured at right angles to centreline at every chainage station — levels at standard offsets plus at all terrain break points within the corridor width
Structure Survey
All culverts, manholes, bridges, and drainage structures surveyed — positions, dimensions, invert levels, conditions, and hydraulic capacity assessment
Civil 3D Processing & Issue
Full corridor model built in Civil 3D — long-sections, cross-sections, chainage schedules, structure inventory, and utility record issued in client-specified formats
Frequently asked questions
Infrastructure Route Survey Questions
What is the difference between a route survey and a topographic survey?
A topographic survey maps an entire site area — capturing all terrain features across the full site boundary in a comprehensive 3D model. A route survey concentrates measurement intensity along a defined linear corridor, prioritising chainage-based level profiles and cross-sections over area-wide coverage.
In practice, the two are often used together: a topographic survey of the project site provides the general terrain context, while route surveys along specific road or pipeline alignments provide the detailed longitudinal and transverse data needed for detailed design. For large infrastructure projects, only route survey of the specific corridor is needed — a full topographic survey of the surrounding area would be unnecessarily expensive and slow.
How far in advance should a route survey be commissioned before design begins?
Route surveys should be commissioned at the preliminary design stage — before detailed design begins — so the design team has verified ground data from the outset. The minimum practical lead time is:
- Short routes (under 2km) — survey can be completed within 1–2 weeks of instruction
- Medium routes (2–10km) — allow 2–4 weeks for survey and processing
- Long routes (10km+) — allow 4–8 weeks depending on terrain and access conditions
Commissioning the survey after detailed design has already begun is the most common and expensive mistake on infrastructure projects in Kenya. Design changes triggered by the survey findings cost far more in design rework than the survey itself would have cost if commissioned first.
Can you survey along an existing road while it is still in use?
Yes. Our standard method for surveys along in-use roads in Kenya uses RTK GNSS rover and total station from the roadside — minimising disruption to traffic. For detailed cross-section measurement at specific chainages, brief lane closures of 2–5 minutes are sometimes required for the cross-section team to measure across the carriageway. We coordinate with the road authority and provide traffic management where required by site conditions.
For urban road surveys in Nairobi CBD, Westlands, and other high-traffic areas, we schedule early morning survey windows (5am–8am) to capture cross-sections before peak traffic builds. Early morning also avoids parked vehicles that obstruct cross-section measurement during the day.
Do you produce drawings compatible with KeNHA design submissions?
Yes. Cadreatech route survey deliverables are formatted to the conventions of the KeNHA Road Design Manual — including drawing scales (1:2000 horizontal / 1:200 vertical for long-sections), chainage and level annotation, cross-section plotting at standard templates, and structure inventory in KeNHA format. Our Civil 3D corridor models are compatible with the software environments used by major design consultants working on KeNHA projects in Kenya.
For KURA urban road projects, KeRRA rural road projects, and county government roads, we confirm the specific drawing format and submission requirements at scoping stage and format deliverables accordingly.
What is included in a culvert survey along a road corridor?
For each culvert encountered along the survey corridor, we record:
- Position (chainage on the road alignment)
- Type — pipe culvert, box culvert, arch culvert, or ford
- Size — diameter for pipes, span and height for box and arch culverts
- Material — concrete, corrugated steel, HDPE, masonry
- Invert levels at inlet and outlet
- Headwall condition — present and intact, damaged, absent
- Blockage status — clear, partially blocked, fully blocked
- Approximate hydraulic capacity assessment relative to the upstream catchment
This culvert inventory is one of the most practically valuable outputs of a road route survey — enabling the drainage engineer to identify which culverts are hydraulically undersized and require replacement or supplementation, and which are adequate for the design storm.
Related services
Services That Work With Route Survey
Request an Infrastructure Route Survey Quote
Tell us your infrastructure type (road, pipeline, sewer, drainage), approximate route length, location, project stage, and required design standard. We will advise on the appropriate survey specification and provide a detailed quotation within 48 hours.
