Site Characteristics & Land Use Impact

Chapter: Site Characteristics & Land Use Impact

This chapter delves into the critical aspects of site characteristics and their profound impact on land use, property valuation, and overall development potential. Understanding these factors is fundamental for accurate property appraisals and informed decision-making related to land development and management. We will explore the scientific principles underpinning these concepts and provide practical applications relevant to property valuation.

1. Introduction: The Site as a System

A property site is not an isolated entity but rather a complex system influenced by a multitude of interacting factors. These factors, encompassing physical, environmental, and regulatory elements, determine the site’s suitability for various uses and ultimately its value. Land use regulations, stemming from zoning ordinances and other legal frameworks, overlay these inherent site characteristics, further shaping the development possibilities and economic viability of the property.

2. Physical Site Characteristics

The physical characteristics of a site are the foundational elements influencing its potential use and value. These characteristics can be assessed through field observations, surveys, and geological investigations.

2.1. Size and Shape

• Description: Size refers to the area of the site, typically measured in acres, square feet, or hectares. Shape describes the geometric form of the site. Key dimensions include frontage (length of the boundary abutting a street or other feature), width, and depth.

• Impact: Size and shape directly affect the buildable area, accessibility, and overall functionality of the site. Unusual shapes can limit development options, while insufficient size may preclude certain uses.

• Scientific Principle: The relationship between site size and value often follows a diminishing returns principle. As size increases, the unit price (e.g., price per square foot) tends to decrease. This reflects economies of scale and the potentially lower demand for very large parcels. Mathematically, we can represent this as:

  • V = A * UP

    Where:

    • V = Total Value
    • A = Area (e.g., square feet or acres)
    • UP = Unit Price (e.g., dollars per square foot or dollars per acre)

    While A increases, UP often decreases, leading to a non-linear relationship between area and value. This is particularly relevant when considering plottage potential.

• Practical Application: When analyzing comparable sales, it is crucial to adjust for size differences. Linear regression analysis can be used to model the relationship between site size and sale price, allowing for more accurate value adjustments.

• Experiment: Collect sales data for similar properties in a given area. Plot the sale price against the site size. Observe the relationship. Calculate the correlation coefficient (r) to quantify the strength and direction of the relationship. A negative correlation would indicate that as size increases, the price per unit area decreases.

2.2. Corner Influence

• Description: Corner lots possess frontage on two or more streets.

• Impact: Corner influence can be either positive or negative depending on the intended use. For commercial properties, corner locations often offer increased visibility and accessibility. However, for residential properties, corner locations may be less desirable due to increased traffic noise and reduced privacy.

• Scientific Principle: The perceived value of corner influence is fundamentally driven by accessibility and exposure. For retail applications, a corner location increases pedestrian and vehicular traffic exposure, directly influencing potential sales revenue. However, increased exposure can translate to disamenities like noise pollution for residential properties.

• Practical Application: Analyze sales of comparable corner lots and interior lots. Calculate the percentage difference in sale prices to quantify the corner influence premium or discount.

2.3. Plottage Potential

• Description: Plottage refers to the increase in value that results from combining two or more adjacent parcels into a single, larger parcel.

• Impact: The combined parcel may have a higher and better use than the individual parcels, leading to a synergistic increase in value.

• Scientific Principle: Plottage value arises from economies of scale, increased development potential, and the ability to accommodate uses that are not feasible on smaller parcels. The increased value must outweigh the costs associated with assemblage, including acquisition costs and potential demolition expenses.

  • Plottage Value = Combined Value - (Sum of Individual Values + Assemblage Costs)

• Practical Application: Identify potential assemblage sites in a given area. Estimate the value of the individual parcels separately and the value of the combined parcel if developed according to its highest and best use. Calculate the plottage value and determine if the assemblage is economically feasible.

2.4. Excess and Surplus Land

• Description:

  • Excess Land: Land that is not needed to support the existing or proposed use and has the potential to be sold off separately and developed independently. It has an independent highest and best use.
  • Surplus Land: Land that is not needed to support the existing or proposed use and cannot be sold off separately due to its size, shape, or location. It does not have an independent highest and best use.

• Impact: Excess land represents a potentially valuable asset that can be monetized through sale or separate development. Surplus land may contribute to the overall value of the property, but its value is typically less than that of comparable vacant land.

• Scientific Principle: The distinction between excess and surplus land hinges on the concept of severability and independent utility. Excess land meets both criteria, while surplus land fails at least one.

• Practical Application: Carefully analyze the land-to-building ratio for the subject property and compare it to the prevailing ratios for comparable properties in the area. Determine if any portion of the site is not necessary to support the existing or proposed use and if that portion can be legally and economically separated and developed.

2.5. Topography

• Description: Topography refers to the shape and contour of the land surface, including its elevation, slope, and drainage patterns.

• Impact: Topography significantly affects construction costs, site accessibility, and the potential for erosion and flooding. Steep slopes can increase construction costs and limit accessibility, while poor drainage can lead to water damage and soil instability.

• Scientific Principle: Topography influences surface runoff, soil moisture content, and solar radiation exposure. These factors directly affect vegetation growth, soil erosion rates, and the suitability of the site for various uses. Understanding slope stability is critical, often analyzed using the Factor of Safety (FS):

  • FS = (Shear Strength) / (Shear Stress)

    A factor of safety greater than 1 indicates stability. Engineering principles are applied to design retaining walls or other solutions to mitigate risks associated with steep slopes.

• Practical Application: Utilize topographic maps and on-site surveys to assess the slope and drainage characteristics of the site. Consider the impact of these characteristics on construction costs, site accessibility, and the potential for erosion and flooding.

2.6. Geology and Soil Analysis

• Description: Geology encompasses the composition and structure of the underlying rock formations, while soil analysis focuses on the properties of the surface and subsurface soils.

• Impact: Geological conditions and soil properties affect the load-bearing capacity of the site, its suitability for septic systems, and the potential for subsidence or landslides.

• Scientific Principle: Soil mechanics principles govern the behavior of soils under load. Soil composition (sand, silt, clay percentages) impacts permeability, drainage, and compaction. Soil bearing capacity dictates the type and scale of structures that can be supported. See soil triangle diagram in file.

• Practical Application: Conduct soil tests to determine the soil’s bearing capacity, permeability, and composition. Consult with a geotechnical engineer to assess the geological stability of the site and identify any potential hazards.

• Experiment: Use the Unified Soil Classification System (USCS) to classify soils based on grain size and plasticity. Perform laboratory tests to determine the soil’s liquid limit, plastic limit, and plasticity index.

2.7. Utilities

• Description: The availability and capacity of essential utilities, such as water, sewer, electricity, gas, and telecommunications, are crucial considerations.

• Impact: Adequate utility infrastructure is essential for supporting development and ensuring the habitability and functionality of buildings.

2.8. Site Improvements

• Description: Existing site improvements, such as landscaping, fencing, paving, and drainage systems, can add value to the property.

2.9. Accessibility

• Description: Accessibility refers to the ease with which people and goods can access the site, including access to roads, public transportation, and pedestrian walkways.

2.10. Environment

• Description: Environmental factors, such as air and water quality, noise levels, and the presence of hazardous materials, can significantly affect property value.

3. Land Use Regulations and Zoning

Zoning regulations are legal instruments enacted by local governments to control land use and development. These regulations specify permitted uses, building height restrictions, setback requirements, and other development standards.

3.1. Zoning Ordinances

• Description: Zoning ordinances divide a municipality into different zoning districts, each with its own set of regulations.

• Impact: Zoning ordinances dictate the types of uses that are permitted on a given site, influencing its development potential and value.

• Scientific Principle: Zoning regulations are based on the concept of Euclidean zoning, which seeks to segregate land uses to minimize conflicts and promote public health, safety, and welfare.

3.2. Setback Requirements

• Description: Setback requirements specify the minimum distance that a building must be set back from property lines.

• Impact: Setback requirements affect the buildable area of a site and can limit the size and configuration of buildings.

3.3. Height Restrictions

• Description: Height restrictions limit the maximum height of buildings in a given zoning district.

• Impact: Height restrictions can significantly impact the density of development and the overall value of a site.

3.4. Floor Area Ratio (FAR)

• Description: Floor Area Ratio (FAR) is the ratio of the total floor area of a building to the area of the lot on which it is built.

  • FAR = (Total Floor Area) / (Lot Area)

• Impact: FAR regulations control the intensity of development on a given site.

• Scientific Principle: FAR controls the bulk and density of buildings, affecting population density, traffic congestion, and the demand for public services.

• Practical Application: Calculate the maximum buildable floor area for a site based on the applicable FAR regulations.

3.5. Floodplain and Wetlands Analysis

• Description: Floodplains are areas that are susceptible to flooding, while wetlands are areas that are saturated with water for all or part of the year.

• Impact: Development in floodplains and wetlands is often restricted due to environmental concerns and the risk of property damage. FEMA maps identify flood zones.

• Scientific Principle: Wetlands provide important ecological services, such as flood control, water filtration, and wildlife habitat. Floodplain regulations are designed to minimize flood damage and protect public safety.

4. Environmental Considerations

Environmental factors play a crucial role in shaping land use and property value.

4.1. Environmental Site Assessments (ESAs)

• Description: ESAs are conducted to assess the presence of hazardous materials or contamination on a site.

• Impact: Environmental contamination can significantly reduce property value and increase the cost of development.

4.2. Wetlands Regulations

• Description: Wetlands are protected by federal and state regulations.

• Impact: Development in wetlands is often restricted or prohibited to protect their ecological functions.

5. Conclusion

Understanding site characteristics and land use regulations is essential for accurate property valuation and informed decision-making related to land development. By carefully analyzing the physical, environmental, and regulatory factors affecting a site, appraisers and developers can make sound judgments about its potential use and value. The interplay between these elements dictates the economic viability and overall suitability of a property for various purposes.