FS Exam Preparation

Comprehensive preparation for the Fundamentals of Surveying (FS) exam. 7 modules covering all 7 exam domains with 60 in-depth topics.

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Lesson 9

Land Development & Subdivisions

Learning Objectives

After completing this topic, you should be able to:

Describe the subdivision process from planning through recording
Explain the surveyor's role in land development projects
Identify the components of a subdivision plat
Understand right-of-way and easement considerations in subdivisions
Describe utility and grading considerations for lot layout
Explain the relationship between preliminary and final plats

Overview

Land development encompasses the process of converting undeveloped or agricultural land into buildable lots, streets, and public spaces. The surveyor plays a central role throughout this process -- from the initial boundary and topographic surveys through final plat preparation and construction staking.

Subdivision is the legal process of dividing a larger parcel of land into smaller lots, typically for sale and development. The subdivision plat is a recorded document that defines the lots, streets, easements, and other elements of the development. Understanding the subdivision process is essential for the FS exam, as it integrates nearly every aspect of surveying practice.

Key Concepts

Figure FS.1.9 — Subdivision Approval Process

The Subdivision Process

Figure FS.1.9b — The subdivision process: feasibility & planning → preliminary plat → construction → final plat (recorded)

The typical subdivision process follows these stages:

1. Feasibility and Planning:

Boundary survey of the parent parcel
Topographic survey for design purposes
Environmental and wetland delineation
Utility availability assessment
Zoning and land use review

2. Preliminary Plat:

Shows proposed lot layout, streets, and easements
Submitted to the local jurisdiction for review and approval
May require public hearings
Subject to revisions based on agency comments
Not a recorded document; serves as the development blueprint

3. Construction:

Grading and earthwork (mass grading)
Street construction (subgrade, base, pavement)
Utility installation (water, sewer, storm, electric, gas, telecom)
Stormwater management facilities
Landscaping and common area improvements

4. Final Plat:

Prepared after construction is substantially complete
Shows the final lot lines, dimensions, areas, and easements
Includes monuments set at lot corners, street intersections, and curve points
Signed by the surveyor, owner, and approving agencies
Recorded in the county records, creating the legal lots

Components of a Subdivision Plat

Figure FS.1.9c — Anatomy of a subdivision plat: 12 required components

A typical subdivision plat includes:

Component	Description
Title block	Subdivision name, location (section, township, range or other reference), county, state
Boundary	Metes and bounds description of the subdivision perimeter with bearings, distances, and curve data
Lots and blocks	Numbered lots organized in blocks; dimensions, areas, and bearings for each lot line
Streets	Right-of-way widths, centerline data, curve data (radius, arc length, chord, delta angle)
Easements	Utility easements, drainage easements, access easements with dimensions
Monuments	Types and locations of monuments set (and found)
Basis of bearings	The reference for all bearings shown on the plat
Notes and certifications	Surveyor's certificate, owner's dedication, agency approvals
Vicinity map	Shows the subdivision location relative to surrounding streets and features
Curve table	Tabulates all curve data: radius, delta, arc length, chord bearing, chord distance
Area summary	Total area, lot areas, street areas, open space areas

Lot Design Considerations

Figure FS.1.9c — Subdivision lot design: perpendicular to street, rear utility easements

Minimum lot dimensions:

Most jurisdictions specify minimum lot width (at the building setback line), minimum lot depth, and minimum lot area
Corner lots typically require additional width to accommodate side setbacks along the street

Lot orientation:

Lots should have frontage on a public street
Side lot lines should be approximately perpendicular to the street (or radial to curves)
Avoid "flag lots" (lots with narrow access strips) unless necessary
Consider solar orientation and view corridors

Grading and drainage:

Each lot must drain to the street or a designated drainage facility
Minimum lot grades: typically 2% away from buildings
Maximum lot slopes: typically 3:1 (33%) for usable areas
Retaining walls may be needed for steep lots

Streets and Right-of-Way

Figure FS.1.9d — Right-of-way widths by street class

Right-of-way (ROW): The public land dedicated for street, sidewalk, and utility purposes.

Street Type	Typical ROW Width	Pavement Width
Local residential	50-60 ft (15-18 m)	24-36 ft (7-11 m)
Collector	60-80 ft (18-24 m)	36-44 ft (11-13 m)
Arterial	80-120 ft (24-37 m)	48-64 ft (15-20 m)
Cul-de-sac bulb	45-55 ft radius	38-45 ft radius

Typical widths consistent with AASHTO, A Policy on Geometric Design of Highways and Streets ("Green Book"), and ITE Recommended Practice for Subdivision Streets; locally adopted standards vary by municipality.

Curve design for subdivision streets:

Minimum centerline radius depends on design speed and street classification
Curve data on the plat includes: radius (R), delta angle, arc length (L), chord bearing, chord distance
Reverse curves (S-curves) should have tangent sections between them

Easements

Easements in subdivisions typically include:

Utility easements: Usually 10-20 ft (3-6 m) wide along rear and/or side lot lines for water, sewer, electric, gas, and telecom
Drainage easements: Along watercourses, storm drains, and detention facilities
Access easements: For lots without direct street frontage (avoid when possible)
Sight distance easements: At intersections to maintain clear sight triangles

Common wrong path — easements along the front of residential lots. On a typical residential subdivision plat, utility easements run along the rear and side lot lines, not along the front. The front of the lot is already within the public right-of-way (the dedicated street area), where utilities are installed in the ROW itself — no separate easement is needed at the front because the entire ROW is public. Students sometimes answer "front lot line" when asked where utility easements are typically placed, which produces a plat with a redundant easement inside the ROW and no coverage at the rear where the utility actually needs to access the lot. The correct answer: easements usually line the rear (for mains) and side (for service laterals) lot lines, 10–20 ft wide, with the front being within the dedicated ROW.

Quick retrieval check — try before reading on.

▶A subdivision plat shows: a 60-ft-wide public street ROW on the front, a 10-ft-wide utility easement on the rear, and 5-ft-wide utility easements on each side. A new sewer main is to be installed serving the lots. Where is the main most likely located, and why?

The main is most likely in the 10-ft rear easement (or within the street ROW, depending on the subdivision's design). Sewer mains in residential subdivisions typically run along the rear of lots when gravity flow requires a specific alignment, or along the street in the ROW when flow direction permits. Service laterals connect from the main to each lot through the side easements.

The 5-ft side easements are usually for service laterals (shallower, smaller utilities like gas, electric, telecom) rather than for major gravity sewers. The front (inside the 60-ft ROW) is where surface utilities like street lighting, hydrants, and shallow utility laterals are installed — no separate easement needed because the entire ROW is already dedicated public area. The question tests whether the student understands the standard arrangement: front = ROW (no separate easement), sides = laterals, rear = primary utility corridor.

The Surveyor's Role

The surveyor is involved throughout the land development process:

Boundary survey of the parent parcel
Topographic survey for engineering design
ALTA/NSPS survey if required for financing
Preliminary plat preparation (or support to the engineer/planner)
Construction staking for streets, utilities, grading
Final monumentation of lot corners and control points
Final plat preparation, signing, and recording
As-built surveys documenting constructed improvements

Exam Tips

A preliminary plat is not recorded; the final plat is recorded and creates the legal lots
The subdivision plat must include a metes and bounds description of the entire subdivision perimeter
Lot lines should be approximately perpendicular to the street centerline (or radial on curves)
Utility easements are typically along rear and side lot lines, not the front (which is within the ROW)
The basis of bearings must be clearly stated on the plat
Curve data required on plats: radius, delta angle, arc length, chord bearing, chord distance
Each lot must have adequate drainage -- typically graded to drain toward the street
The FS exam may test your understanding of plat components or lot design principles
Right-of-way is dedicated to the public; easements grant specific use rights while the underlying ownership remains with the lot owner

FS Exam Preparation

Module 1: Surveying Processes & Methods

Module 2: Mapping Processes & Methods

Module 3: Boundary Law & Real Property

Module 4: Surveying Principles & Geodesy

Module 5: Survey Computations

Module 6: Business Concepts

Module 7: Applied Math & Statistics