Study Guide Ch. 3 Site Inventory and Analysis Flashcards
Site inventory
a process of documenting various site data
Site analysis
follows the site inventory, and it requires the landscape architect to interpret the site inventory data to make conclusions relevant to the design process.
Remember that inventory is ONLY the act of collecting data and that any conclusions drawn from site data is analysis.
site inventory might involve:
- Identifying the locations of specimen trees
- Acquiring topographic data of the site
- Cataloging the soils found on the site
When translated to the site analysis phase, these may yield information including:
- Suggesting that site access occur in locations without specimen trees
- Conducting a slope analysis to site a building
- Determining that the site's soils cannot support stormwater infiltration
Site Inventory Process
- A community’s natural and cultural resources need to be identified so that they can be incorporated into decision-making processes by public and private sector interests, and this is the role of the site inventory process
- guided by the site program and site selection process, and these factors play a critical role in determining the scope of site inventory
- the limitations imposed by project schedules, budgets and development regulations (e.g. permitting requirements) means that site inventory and analysis should focus on data relevant to the proposed project, and the proposed program plays a key role in determining what data should be collected and analyzed
- not only originates from the site program and the site selection process, it can also influence the site program and site selection (shown in the dashed lines) and initiate another round of site selection or introduce new ideas for the site program.
Site reconnaissance
- relatively informal site assessment is intended to be conducted quickly and allow the landscape architect or client to identify site assets and liabilities that are relevant to the proposed project
- may take the form of an in-person site visit, but it may also involve reviewing basic site data, such as an existing survey of the site
- After the initial reconnaissance—and if the site meets the basic project criteria—the landscape architect would then develop a base map
Base map
- developed after site reconnaissance
- not only used to catalog the site's attributes, it is also used for site analysis and is a template for any subsequent land planning and design that may occur on this site
Community resource inventory
- type of site inventory
- map wetlands, archaeological sites, scenic views and significant wildlife habitats as well as ecological and cultural resources such as forests, floodplains, farmland, aquifers and historic structures.
The base map
- The precise contents of a base map will vary according to the scope of a project, and some projects may use a simple aerial image of the site (e.g. Google Earth) to conduct an initial site assessment
- for LARE, we can generally expect that the base map will be generated from an ALTA (American Land Title Association) survey and will generally contain the following data
Base map typical data
Property boundary***
Public rights-of-way
Easements
Topography
Existing buildings
Existing utilities
Flood zone classifications
Adjacent property uses and owners
As with other types of maps, the base map will also include such basic information as:
Site location map (a small-scale map showing the site within its community context)
Title information (i.e. project name, location, designer, consultants)
North arrow
Graphic map scale
Data sources (date of site boundary survey, name of surveyor, and other source data)
***Note: Some sources erroneously state that an ALTA survey does not include a property boundary. According to the ALTA/NSPS Survey Requirements 2021, ALTA surveys do indeed include boundary information, stating the following: “Boundary – The boundary lines and corners of any property or interest in real property being surveyed (hereafter, the “surveyed property” or “property to be surveyed”) as part of an ALTA/NSPS Land Title Survey must be established and/or retraced in accordance with appropriate boundary law principles governed by the set of facts and evidence found in the course of performing the research and fieldwork.”
USGS Topographic Maps
Sometimes referred to as USGS quadrangle maps or 7.5-minute quadrangle maps, these maps are generally available at 1:24,000 scale, and they would contain information such as:
Topography (typically at 40' contour intervals)
Township, range and section information
Transportation infrastructure
Rivers, floodplains, wetlands and basic physiographic data
Buildings and new construction since the last printing (for rural areas)
free, publicly available data
With that said, these maps stopped being printed in 2006 and are now updated and made available as GIS data sets that can be downloaded free of charge. The USGS printed maps (from 1884-2006) have been scanned and input into GIS and are now referred to as the Historical Topographic Map Collection (HTMC).
A base map is not necessarily a static entity. If a project site is large (e.g. 500 acres) or if multiple project sites are being investigated simultaneously, it may make sense for the initial base map to draw from
Public Land Survey System (PLSS)
a method of dividing land (for the purpose of sale) that is specific to the United States
used in most—but not all—regions of the United States
primary units of this nested grid system are townships (six-by-six-mile squares), sections (one-by-one-mile squares, or 640 acres), and quarter sections (160 acres), with the section being the primary unit in this system
At 24-by-24-miles square, the quadrangle is the largest unit of the PLSS system
ALTA survey
Sometimes referred to as a "title survey," an ALTA (American Land Title Association) survey is a common survey used to record a property for a real estate transaction
ALTA surveys document a wide variety of information on a site and will generally contain the following data
Property boundary***
Public rights-of-way
Easements
Topography
Existing Buildings
Existing utilities
Flood zone classifications
Adjacent property uses and owners
As-built survey
The purpose of an as-built survey is to document a final built work and ensure that a project was constructed according to the construction documents
generally conducted over the course of construction to fully document all site elements as they exist in the real world, and the location and nature of these site elements may differ from that shown on a landscape architect’s site plans due to a variety of factors.
Boundary Survey
used to define the boundaries of a parcel of land
typically conducted before subdividing, improving, or building on land, and they are often incorporated into other scopes of survey work, including an ALTA survey.
Property boundaries are described using a system of bearings established at specific survey-located points (e.g. property corners).
Topographic Survey
topographic information is often conducted as part of the scope of an ALTA survey
there are numerous instances when a client or designer needs updated or higher resolution topographic information and—in these instances—they would commission a topographic survey
Topographic surveys generally include:
- Topographic contours with contour intervals determined by the client/designer. Most design work uses 2’ contour intervals with additional spot elevations
- Spot elevations (highly accurate measurements of specific site elements – for example the top of a wall or the bottom of a staircase)
- Vegetation and physical attributes including streams, rock outcroppings and wooded areas
- Utilities
Aerial Photography
is generally used for documenting static, high-contrast and large-scale phenomena, such as buildings and differences between vegetated and non-vegetated areas. They may also be used as a raster image in GIS as a background to other data
Backsight
a point used to determine the elevation and/or angular orientation of the surveying instrument.
