Site Analysis Flashcards
Public Land Survey System and types of land division
The Public Land Survey System (PLSS) is a way of subdividing and describing land in the United States. All lands in the public domain are subject to subdivision by this rectangular system of surveys, which is regulated by the U.S. Department of the Interior, Bureau of Land Management (BLM).
The PLSS typically divides land into 6-mile-square townships. Townships are subdivided into 36 one-mile- square sections. Sections can be further subdivided into quarter sections, quarter-quarter sections, or irregular government lots. Normally, a permanent monument, or marker, is placed at each section corner.
Easement
The right ot use another’s land for a specific purpose, or to prevent the land’s owner from using it for a particular purpose.
Types of Easements
- Utility
- Access (if there is no road, right to cross the property_
- Support (construction of common party wall)
- Joint Use (allow 2 or more owners to share a common feature like a driveway)
- Scenic (protect views and development in scenic areas)
- Conservation (limit land use in large areas)
Right of Way
Legal right of one party or the public to traverse land belonging to another (streets and sidewalks)
Restrictive Covenant
Limits on how a property owner can use or improve the property. Contained in the deed of the property.
Mill Levy
Property taxes expressed as a number of mills, or thousandths of a dollar, that are charged per $1000 of assessed value. Assessed property value is a % of actual land value (% fixed by taxing authority). Yearly Tax = (assessed land value x mill levy) / $1000
3 Ways to Assess Land Value
- market approach (similar properties cost)
- income approach (potential for property to earn a profit)
- cost approach (how much a property would cost to replace (meaning, rebuild) after subtracting accrued depreciation)
Ways to assess existing vegetation
- Look for second growth vegetation as indication of past activities
- Previous disturbance
- Quality of vegetation
- Presence of water-tolerant plants may indicate high water table or floods.
- Poor quality or stressed vegetation may indicate problematic soil or subsurface conditions.
Degree days
Degree days are measures of how cold or warm a location is. Adegree daycompares the mean (the average of the high and low) outdoor temperatures recorded for a location to a standard temperature, usually 65° Fahrenheit (F) in the United States. The more extreme the outside temperature, the higher the number of degree days. A high number of degree days generally results in higher levels of energy use for space heating or cooling.
Sensible heat
Sensible heat is the energy required to change the temperature of a substance with no phase change. The temperature change can come from the absorption of sunlight by the soil or the air itself. Or it can come from contact with the warmer air caused by release of latent heat (by direct conduction). Energy moves through the atmosphere using both latent and sensible heat acting on the atmosphere to drive the movement of air molecules which create wind and vertical motions.
Latent heat
Latent heat is the energy absorbed by or released from a substance during a phase change from a gas to a liquid or a solid or vice versa.
100 Year flood
Statistically 1 in 100 chance of a flood occuring in a given year (1% chance per year). NOT probability that flood will occur once in 100 years. Known as Base Flood for regulating 1st floor building elevation and for insurance purposes.
Special Flood Hazard Area
Area affected by a Base Flood (100 year floodplain). Determined by Base Flood Elevation for a particular area.
FIRM
Flood Insurance Rate Maps. Provided by FEMA based on analysis of previous soils maps, flood data and photos. More flood prone areas have detailed maps, and others have approximate maps.
Water table
Highest point groundwater rises.
Wetland
Environment characterized by shallow or
fluctuating water levels and abundant aquatic and marsh
plants, Includes marshes, swamps, bayous, bogs, fens,
sloughs and ponds. Do not build within 100 ft.
Gray Water
Domestic wastewater, composed of wash
water from kitchen, bathroom and laundry sinks, tubs
and washers. Does not include human waste. Black water = sewage.
Runoff
Surface streams that appear after precipitation and irrigation. A lost resource and contributor to nonpoint source pollution.
Dry Floodproofing
Protects a building by making it watertight and reducing the possibility that a building will be inundated with water. A few measures are: • Continuously impermeable walls • Flood shields • Patch non-required openings • Internal drainage and sump pumps
Wet Floodproofing
Protects a building by modifying the interior so that flood waters that do enter the building cause minimal damage. Wet floodproofing does not attempt to stop water from getting in. A few methods:
• raise utilities and important systems above the
predicted flood level
• install flood openings to equalize hydrostatic pressure
• install pumps to remove water after flooding
Phytoremediation
Using plants to remediate contaminated soil in situ
Bioventing
In situ remediation technology. Injects air into contaminated soils above water table. Increase of oxygen causes natural microorganisms to degrade the pollutants at an accelerated rate.
Kips to lbs
1 kip = 1000 lbs
Silt fence
A temporary sediment control device used on construction sites to protect water quality in nearby streams, rivers, lakes and seas from sediment (loose soil) in stormwater runoff. Silt fences are widely used on construction sites in North America and elsewhere, due to their low cost and simple design.
Parking design rules of thumb
9x20 standard space, 8x20 + 5x20 aisle for accessible space (located max 200’ from entrance). 90 degree parking is most efficient in terms of land use. Diagonal parking is better for traffic flow, easier to use and has a narrower aisle. Drive aisle 20-24’ wide for two way. 300-350 SF per car including half drive aisle.
Topographic maps rules of thumb
- The highest point of a hill is just below the value of the next possible contour line.
- V shaped contours indicate a river and the tip of the V points to the source of the water.
Slopes and widths for sidewalks
Running slope: 5% Cross slope: 2% 5' standard width 6' wide when cars overhang edge See ballast 12-5 drawing of road on contour map
Curb cut accessible slopes
1: 12 running slope
1: 10 cross slope
Optimal building orientation: generally and specific for each climate type
15° East of South generally to take advantage of cooler temps in the morning to offset heat gain of direct solar gain through SE windows Hot-humid: 5° Cool: 12° Temperate: 17.5° Hot-arid: 25°
