TOPOGRAPHIC

WHAT IS AN TOPOGRAPHIC SURVEY?

Before undertaking any development project, it may be necessary to perform a topographic survey to identify various features of the land. Topographic surveys identify important characteristics of a defined plot of land. While a boundary survey deals primarily with marking out a parcel's boundaries, a topographic survey is more concerned with noting the natural and manmade features on the land itself. A topographic survey shows these features' locations, sizes, and heights, as well as elevation contours.

Moreover, topographic surveys focus on elevations other than horizontal measurements. The results are not marked using stakes or other landmarks but instead are drawn as contour lines on a map of the land, resulting in them sometimes being called contour surveys. Today, computer programs allow for digital versions of these maps, as well as interactive elevation views of the land.

IMPORTANCE OF GETTING A TOPOGRAPHIC SURVEY:

Topographic surveys have many uses. They are useful when a parcel of land that was previously in use is being redeveloped—for example, an abandoned quarry or landfill, a site where a building was demolished, or on a site where the topographic data is changing. In these cases, a topographic survey provides an accurate view of how the land has been changed by its use, allowing for better planning for future use.

Residential: Reasons landowners may need a topographic survey are to help in the design of road improvements, landscape improvements, buildings, remodels, and additions or when locating trees, fences, walls, buildings, sheds, or other outdoor structures. Topo surveys assist in identifying property slope and contours for potential construction projects or property use analysis

Construction: Nearly all construction projects begin with a topographic land survey, which describes the starting point of the land before improvements are made. Topo surveys may also be used when creating plans for drainage ditches, grading, or other features, using the natural landscape as the basis for such improvements.

Engineers/Architects: Design professionals use topo surveys as an aid in designing buildings or other improvements to be situated on the property, as existing features may influence their design or decisions on where structures can and cannot be placed on the property. The data of a topo survey is also used in AutoCAD programs, where it can be manipulated by engineers or architects to demonstrate how the topography will change through planned improvements.

Legal: Government agencies may also require topographic surveys for any of a number of reasons—for example, as regulatory requirements for construction codes, or as part of environmental restoration projects.

WHAT IS INCLUDED WITHIN A TOPOGRAPHIC SURVEY?

A topographic survey map details existing site conditions over the natural state of the land as well as features that exist on the 

ground or slightly above or beneath the earth’s surface. These features include:

LEGAL BOUNDARIES
IMPROVEMENTS
SITE CONTOURS
TREES
RAVINES
PROPOSED & EXISTING STRUCTURES
UTILITIES
FENCES
HILLS
STREAMS

OTHER TYPES OF TOPOGRAPHIC SURVEYS:

The following are focuses that can be included in a topographic survey, however, these are very much site dependent and are 

often not necessary in a standard topo. Extra costs may be associated.

Subsurface Utility Mapping/SDOT

Subsurface utility mapping involves reporting on as-built conditions of utility infrastructure (ie. electric, gas, water, etc). Privately-owned underground utilities between the meters make it essential to perform extensive underground utility location, especially on commercial projects. By locating utilities, one can avoid later design issues and avoidable costs.

Drainage Survey

A drainage survey shows the direction in which the water on a particular piece of property will drain. These types of surveys are usually required by the city to prove that properties don't pose a flood risk in the event of heavy rain. This is of particular concern in the Puget Sound Region.

Setback Survey

A building setback on a survey is the distance the building is set back from a street, alley, or property line. Setbacks are set up by land developers. Different for every subdivision, they prevent structures from being built too close together and avoid fire spread, and serve as utility easements for local power or water companies, allowing them to gain access to properties where meters are located.

Ground Control Points (GCP)

Ground control points are points on the ground with known coordinates. In an aerial mapping survey, GCPs are points that the surveyor can precisely pinpoint; with a handful of known coordinates, it’s possible to accurately map large areas.

BOUNDARY

BOUNDARY

ALTA/ACSM

ALTA/ACSM

CONSTRUCTION

CONSTRUCTION

FEMA

FEMA

CONFLICT RESOLUTION

CONFLICT RESOLUTION