Study Guide Ch. 9 Other Design Topics

Question 1

Crime Prevention

Question 2

CPTED

Answer 2

Crime Prevention Through Environmental Design

Regarded as singers outdated and in need of revision
Appears on section 3

Question 3

Five key concepts of CPTED

Answer 3

1. Defensible space
2. Natural access control
3. Territorial reinforcement
4. Natural surveillance
5. Management and Maintenance

Question 4

Defensible Space

Answer 4

Most important term
Physical and suggested/psychological/social barriers that define a size for the purposes of surveillance and control by the site owner.

Defensible space design consists of the concepts of:
- territory (public and private space)
- access (providing or restricting access)
- surveillance (seeing and being seen)

Question 5

Natural access control

Answer 5

Uses defined entry points and other physical barriers to limit access to a specific site.
CPTED principles state that limiting access decreases opportunities for crime and make a site feel safer to its users by defining ownerships of a space

Question 6

Territorial Reinforcement

Answer 6

Companion concept to natural access control that uses design features such as plant materials, hardscape, walls and fences to delineate a “sphere of influence” (usually private vs. public space)
In doing so, territorial reinforcement (supposedly) deters potential criminal offenders from entering a space by making it clear that they have entered a highly maintained or controlled space.

Question 7

Natural Surveillance

Answer 7

Uses site and architectural design to create spaces that maximize visibility to increase safety.
Examples of natural surveillance include windows that look out onto public spaces, adequate nighttime lighting and active, pedestrian-friendly streetscapes

Question 8

Management and maintenance

Answer 8

Entails keeping the site in good working order to convey a sense of safety and security and to ensure that security features (e.g., lighting, entry gates) are operational and effective)

Question 9

CPTED principles are implemented in three ways

Answer 9

Electronic methods
Design methods
Organizational methods

Question 10

Electronic methods

Answer 10

Mechanical security products, target-hardening techniques, locks, alarms, closed circuit television (CCTV), and gadgets.
Note that security lighting does not prevent or stop crime outright, but it can augment a broader security strategy and make sure users feel safer. When used, site lighting should be uniform and consistent, allow for people to clearly identify one another from a moderate distance (~25 ft.) and avoid sharp drop-offs in lighting (i.e., extremely bright to extremely dark)

Question 11

Design methods

Answer 11

Building design and layout, site planning, planting, signage, and circulation control all contribute to site safety.
Examples of CPTED-friendly design methods include minimizing blind spots produced by corners, eliminating dead-ends that make users feel trapped, regulating vehicular access points and by using plant materials that allow for uninterrupted line of sight across a site or specific space.

Question 12

Organizational methods

Answer 12

Site security, receptionists, doormen, and regulating hours of operation or site access

Question 13

CPTED friendly planting plans provide clear lines of sight between 3-6 ft. of height

Answer 13

Designers should plant materials that grow less than 3 ft. in height at maturity to deter hiding or predatory behavior
Trees are acceptable, but should be pruned to remove branches below approximately 6 ft. in height

Question 14

Schools experience elevated levels of crime due to the predictable routines that define educational programming

Question 15

Grading

Question 16

Character of slopes

Answer 16

0-3% nearly level
3-7% gently sloping
7-12% moderately sloping
12-25% strongly sloping
25-40% steeply sloping
40-70% very steeply sloping
70+% extremely sloping

Question 17

Primary purposes of grading

Answer 17

- alter the relative steepness of a slope to control the path and velocity of stormwater runoff
- provide a gradient that meets a specific programmatic demand
- facilitate the safe movement of people and vehicles across a site

Question 18

Recommended gradients

Answer 18

Minimum slope necessary for proper drainage: 2%
Athletic fields: 1-2% (with 1% preferred)
Sidewalks: 1-5%, with 2% cross slope
Streets: 1-10% (max. 20%)
Parking lots: 2-3% (max. 5%)
Sitting areas: 1% (max. 2%)
Lawns: 5-10% (max. 25%)

Townhouses and other forms of multi-family residential development are well-suited to accommodate slopes of between 5-10% because they can make use of split-level designs on steeper slopes

Question 19

Order of operations

Answer 19

Step 1. Site preparation
Step 2. Bulk excavation
Step 3. Backfilling/fine grading
Step 4. Finish surfacing

Question 20

Cut is more stable than fill

Question 21

Sediments pose a significant threat to waterways

Answer 21

- they introduce fertilizers and pesticides into aquatic ecosystems
- reduce steam channel and reservoir capacity
- increase the likelihood of flooding

Question 22

Highest rates of surface erosion occur on construction sites

Answer 22

Largely because construction activities remove existing vegetation, thereby exposing bare soil to the elements

Agricultural lands produce significant amounts of sediment

Question 23

Vegetative cover prevents soil erosion by

Answer 23

- slowing the velocity of runoff through increasing surface friction
- holding soil in place with root systems
- increasing the absorption capacity of the soil through root systems
- shielding soil from the impact of raindrops

Question 24

Sediment and erosion mitigation on construction sites involves two basic steps:

Answer 24

Minimizing the amount of land disturbed (erosion control)
Limiting the damage caused by sediments (sediment control)

Question 25

Erosion control best practices include

Answer 25

- limiting disturbance to the greatest extent possible
- scheduling grading to avoid periods of highest erosion potential (spring thaw/rainy season) and by favoring dry periods of the year, as they have the lowest erosion potential
- limiting grading activities to areas of the site currently under construction and stabilizing the soils (e.g., hydroseeding, mulching) in this areas after grading and construction is complete
- locating non-point pollution sources (e.g., soil stockpiles, construction access roads) away from steep slopes, highly erodible soils, and areas that drain directly into water bodies
- covering and stabilizing soil stockpiles
- constructing benches, terraces or ditches at regular intervals to divert runoff away from areas being graded, to minimize steep slopes and to reduce runoff velocity
- lining drainage channels with stabilizing materials (e.g., rip-rap)
- adding check dams in swales or channels to reduce the runoff velocity

Question 26

Effective erosion control reduces the size and cost of sediment control measures.

Question 27

Detention (settling) and filtration are the main techniques for removing sediment from runoff, and construction site sediment controls include:

Answer 27

- sediment basins
- sediment traps
- filter fabric fencing
- straw bale barriers
- drain inlet protection traps
- vegetated filter strips

In addition, construction entrances should be placed in locations where equipment will be least likely to track mud and other sediment off the site.

Question 28

Stormwater Management

Answer 28

Is about controlling the volume, concentration, and quality of surface runoff on a site.

Question 29

Surface runoff

Answer 29

Precipitation that runs off the land’s surface and flows downhill following the prevailing topography

Question 30

Influence the amount of runoff

Answer 30

Precipitation
Soil type
Slope
Vegetation

areas with low-permeability soils, steep slopes, and large areas of impermeable paving will have more surface runoff than areas with highly permeable soils, gentle slopes and little paving. In short, complex land covers will result in less runoff, and development tends to reduce land cover complexity, thereby increasing the volume and rate of stormwater generated on a site

Question 31

Low impact development (LID)

Answer 31

A process of sustainable stormwater management tends to emphasize distributed, small-scale controls that emulate natural hydrological processes

Question 32

LID techniques encourage

Answer 32

- Retaining, evaporating, and infiltrating excess runoff created by development (i.e., impervious surfaces)
- Preserving existing natural hydrological features (e.g., wetlands, floodplains, stream buffers) and existing vegetation
- Limiting the area disturbed by construction activities
- Controlling stormwater at its source
- Discouraging large, contiguous areas of impervious surface
- Lengthening the “flow path” of stormwater and dispersing drainage across pervious and vegetated surfaces
- Encouraging the use of non-structural “green” infrastructure (e.g., planted swales and rain gardens) rather than hard-lined, engineered structures

Question 33

LID practices benefits

Answer 33

- reduction in stormwater volume and velocity (achieved primarily through infiltration)
- an increase in pervious surface (e.g., vegetated LID planters and other planting areas) and improvements to water quality

Question 34

Examples of LID techniques

Answer 34

green roofs, bioretention facilities and rainwater harvesting systems, and these are typically designed to operate in a specific sequence called a “treatment train.”

Question 35

Best management practices (also known as BMP) typically outline the following suggested sequence for a treatment train

Answer 35

Step 1: Green roof

Step 2: Permeable pavement

Step 3: Bioretention basin with underdrain

Step 4: Water harvest/re-use cistern

an effective stormwater treatment train is ordered according to how precipitation would move through a site

rain first hits the green roof (step 1), then hits the pavement (step 2), after which it travels into a bioretention basin (step 3) to improve water quality, before being directed into a cistern (step 4). Also note that the first three steps offer adequate opportunities for infiltration, thereby reducing stormwater volume. The end result is a system that slows, cools, cleans and infiltrates stormwater to a standard equal to the predevelopment condition on a site.

Question 36

stormwater systems are typically designed to a standard equal to the predevelopment condition on a site

Answer 36

With that said, stormwater management should also consider the impact of drainage from other sites onto the subject site, as well as how drainage from the site flows

Question 37

The LARE candidate should ensure that stormwater runoff never flows directly into a body of water or wetland. It must be intercepted and treated prior to being released into the broader ecosystem.

Answer 37

Topography dictates drainage patterns (recall that water flows perpendicular to a contour line), therefore, site topography and the presence of water features will determine the location of stormwater treatment areas that must be located on any graphic/advanced-type question

Question 38

sustainable stormwater management practices should

Answer 38

- Preserve predevelopment stormwater volume
- Treat, re-use and infiltrate stormwater on-site (dependent on soil conditions)
- Improve water quality by reducing non-point source and thermal pollution
- Promote groundwater recharge
- Lower peak storm flow frequency and duration
- Manage precipitation during extreme weather to reduce downstream flooding risk
- Reduce soil erosion, stream siltation, and downstream scouring
- Reduce potable water demand through the capturing and reuse of precipitation

Note that in addition to the direct impacts on hydrological systems described above, stormwater management should also be treated as an opportunity to provide wildlife habitat, provide sites with a unique character, improve aesthetics and enhance or otherwise support human recreation.

Question 39

Stormwater volume is typically visualized using

Answer 39

A hydrograph

Question 40

Note that this question will likely ask you to identify storm pulses on a hydrograph or deduce that storm pulses are more dramatic on a site after development has occurred and that the time lag between a precipitation event and a storm pulse is reduced by development

Question 41

Impervious surfaces increase the volume and rate of runoff - the most common ways to reduce impervious surfaces on a site

Answer 41

- Reduce the footprint of a structure
- Use green roofs
- Reduce road lengths and widths
- Reduce the size of parking areas by altering dimensions of parking spaces or reducing available spaces
- Replace impervious surfaces with pervious materials/surfaces

Question 42

Base Flow

Answer 42

the sustained flow of a stream (or groundwater) in the absence of direct runoff. It includes natural and human-induced stream flows. Natural base flow is sustained largely by groundwater discharges.

Question 43

First Flush

Answer 43

the initial surface runoff from impervious surfaces with high proportions of concentrated pollution compared to the remainder of the storm. Because the most common rain events are relatively small and contain the most pollutants, designers can emphasize capturing and treating the first flush of runoff from frequent small rain events when managing runoff for water quality.

Question 44

Non-Point Source Pollution

Answer 44

pollution caused by rainfall or snow melt moving over and through the ground, during which it absorbs and/or assimilates natural and human-made pollutants and deposits them into lakes, rivers, wetlands, groundwater and the ocean.

Question 45

Total maximum daily load (TMDL)

Answer 45

the calculation of the maximum amount of a pollutant allowed to enter a waterbody so that the waterbody will meet and continue to meet water quality standards for that particular pollutant. A TMDL determines a pollutant reduction target and allocates load reductions necessary to the source(s) of the pollutant.

Question 46

materials should be selected for

Answer 46

their suitability to the proposed program and regional climate, as well as for their durability and environmental impact

Note that regional, sustainably harvested, and reused/recycled materials are considered to have a low environmental impact

Question 47

Embodied energy

Answer 47

the energy consumed by all of the processes associated with the production of a material

can also be used to determine environmental impact

Note that "embodied energy" is sometimes referred to as "embodied carbon."

Question 48

ranked common materials according to their embodied energy from highest to lowest

Note that the relative ranking of these materials is important, not the specific metrics associated with each.

Answer 48

Aluminum
PVC
Steel
Imported Granite
Asphalt
Kiln-dried lumber
Bricks
Local granite
Concrete
Gravel
Sand

Question 49

Materials sample boards

Answer 49

provide physical samples of the actual materials proposed for use in a landscape architecture project. As such, the quality, finish and other characteristics shown in the sample are identical to what would be/will be used in a given project. Because of this, materials sample boards are considered superior to photographs, cutsheets and renderings of potential materials

Question 50

Aggregate

Answer 50

Advantages

- Economical surfacing material
- Range of colors

Disadvantages

- Requires replenishment every few years depending on level of use
- Allows weed growth
- Requires edging

Question 51

Asphalt

Answer 51

Advantages

- Low heat and light reflectivity
- Versatile, durable and appropriate for year-round use
- Low maintenance costs
- Water repellant (but can be made porous)
- Adaptable to a variety of shapes

Disadvantages

- Degradation at edge without support
- Can soften in extreme heat
- Susceptible to freeze damage

Question 52

Brick

Answer 52

Advantages

- Non-glare and non-skid surface
- Wide color range
- Easily repaired

Disadvantages

- High installation cost
- Difficult to clean
- Can disintegrate in cold weather
- Susceptible to differential settlement and efflorescence

Question 53

Concrete

Answer 53

Advantages

- Easy to install
- Wide range of colors and finishes
- Versatile, durable and appropriate for year-round use
- Low lifetime maintenance costs
- Hard, resilient surface
- Adaptable to a variety of shapes

Disadvantages

- Joints are required
- Difficult to color evenly and permanently
- Can disintegrate if not properly installed and/or from deicing salts
- Reflects light/glare
- Can crack easily

Question 54

Flagstone

Answer 54

Advantages

- Very durable
- Natural weathering

Disadvantages

- Moderately expensive to install
- Can be slippery in wet weather
- Color and patterns can be difficult to match

Question 55

Granite

Answer 55

Advantages

- Very durable, hard and dense
- Will support heavy traffic

Disadvantages

- Relatively expensive to install
- Can be difficult to work with/shape

Question 56

Turf Grass

Answer 56

Advantages

- Non-abrasive, comfortable
- Low installation costs
- Good drainage characteristics

Disadvantages

- Difficult to maintain under heavy use
- Requires significant resource inputs (i.e., water, fertilizer)

Question 57

Material Safety Data Sheet (SDS)

Answer 57

The SDS lists the hazardous ingredients of a product, its physical and chemical characteristics (e.g., flammability, explosive properties), its effect on human health, the chemicals with which it can adversely react, handling precautions, the types of measures that can be used to control exposure, emergency and first aid procedures, and methods to contain a spill. When new regulatory information, such as exposure limits, or new health effects information becomes available, the SDS must be updated to reflect it. Contractors are typically required to have SDS information present on a construction site.

Question 58

Paving Patterns

Answer 58

Running Bond
Stacked Bond
Herringbone
Basket Weave

Question 59

Permeable (Pervious) Pavement

Answer 59

Comprised of pervious asphalt, pervious concrete, interlocking pavers, and plastic grid pavers, permeable pavement allows rain and snowmelt to seep through the surface down to underlying layers of soil and gravel. In addition to reducing runoff from precipitation, permeable pavements can help filter out pollutants and cool surfaces, thereby improving water quality. Permeable pavements can also reduce the need for road salt and reduce construction costs for residential and commercial development by reducing the need for some conventional drainage features. Note that permeable paving requires routine maintenance (e.g., vacuuming) to ensure that void space in the pavement has not been filled in by fine sediments. Therefore, maintenance costs of permeable paving tend to be higher than that of conventional, impermeable paving.

Question 60

Weather Considerations

Answer 60

Cold weather climates place specific stresses on materials, most notably through sanding, salting, and plowing during winter months. These maintenance procedures will quickly degrade many materials. Granite curbs are used in many northern cities for this reason.

Note that salt water is highly corrosive, and stainless steel is the best metal suited for use near an ocean or salt water environment.

Finally, note that non-slip materials should be used in any environment with significant amounts of precipitation or near water features and water bodies of any kind.

Question 61

Linear Feet

Answer 61

a unit of measurement used for linear elements (e.g., PVC pipe, steel header, curb) where the cross-section of those materials remains consistent throughout the project.

Question 62

Square Feet

Answer 62

a unit of measurement typically reserved for fixed hardscape elements (e.g., bricks, pavers, concrete) that can be understood via plan view and where the vertical cross-section of those materials remains consistent throughout the project.

Question 63

Cubic Feet / Cubic Yards

Answer 63

units of measurement that are reserved for loose project materials with three-dimensional qualities, including soil, gravel and mulch. Materials ordered by or measured in cubic yards are often not “finish-quality,” but are used for structural purposes and can be ordered in bulk because they tend to be inexpensive, and their use does not tend to require great precision.

Question 64

Tonnage

Answer 64

a unit of weight, tonnage can be used for some of the materials that are also measured in cubic yards (e.g., gravel). Tonnage is often used to measure stones and boulders because they are heavy, have irregular shapes and because their weight remains consistent regardless of weather conditions (i.e., one ton of granite yields the same quantity of stone regardless of being wet or dry, whereas the same cannot be said of mulch).

Question 65

Project Construction Budget

Answer 65

the amount of money that the client has allocated to have the project built, and the landscape architect will typically be required to produce a design for the client that meets their construction budget. An effective landscape architect will be capable of maximizing a design’s impact within these budgetary constraints, and they will also often be asked to produce an estimate of the proposed design's construction cost.

Question 66

opinion of probable cost

Answer 66

often used for construction cost estimates produced by the designer. The opinion of probable cost is based upon quantity takeoffs, details and specifications and—although it is intended to be accurate—is it not intended to be authoritative. This document is typically produced early in the lifecycle of a project, and although it may be a reference point for a later construction bid, it is not considering binding in any way.

Question 67

Contingency

Answer 67

Note that estimates (including bid prices) will typically include a contingency intended to act as a buffer for unforeseen circumstances. This contingency typically ranges between 5-10% but can be as high as 20% in those instances where the scope of project is uncertain or if there is a high degree of risk associated with a project.

Question 68

Performance Metrics

Answer 68

a relatively new aspect of landscape architecture practice

according to the Landscape Architecture Foundation (LAF), “Landscape performance can be defined as a measure of the effectiveness with which landscape solutions fulfill their intended purpose and contribute to sustainability.” The LAF publishes the “Landscape Performance Series,”

These measures are used to quantify the benefits of a designed landscape and to better inform a client and design team as they try to balance a project’s budget, schedule, and demands.

Question 69

Sustainable Sites Initiative (SITES)

Answer 69

the first comprehensive rating system that guides, evaluates and certifies a project’s sustainability in the planning, design, construction and management of landscapes.
Like LEED, SITES is a voluntary program characterized by a list of credits and prerequisite standards (outlined on the “SITES Scorecard”), and these are used to evaluate a project’s sustainability.
However, whereas the LEED program primarily applies to high-performance, sustainable buildings and tends to be prescriptive in nature (i.e., it emphasizes point-counting and focuses largely on product specifications), the SITES program is used to evaluate landscapes performance from a holistic, system-based perspective. Note that the LEED program does award points for project siting (i.e., locating on a previously developed piece of land) and therefore does take some non-architectural factors into consideration

Question 70

SITES is centered around the idea of ecosystem services and has the following goals

Answer 70

- Create regenerative systems and foster resiliency
- Ensure future resource supply and mitigate climate change
- Transform the market through design, development and maintenance practices
- Enhance human well-being and strengthen community

Question 71

The ASLA publication “A Landscape Performance + Metrics Primer for Landscape Architects” provides an in-depth analysis of the variables that constitute landscape performance, as well as some of the tools used to obtain performance measurements. Key areas of concern are:

Answer 71

- Weather, Microclimate, Air Quality and Sound
- Soils and Amendments
- Water
- Vegetation
- Society and Culture
- Economics

Question 72

Weather, Microclimate, Air Quality and Sound

Answer 72

Examples of metrics include temperature and noise levels, with data collected by tools such as infrared thermometers, thermal cameras, weather stations, remote data loggers and handheld recording devices

Question 73

Soils and Amendments

Answer 73

Examples of metrics include physical (e.g., particle size and distribution), chemical (e.g., pH) and biological (e.g., soil organic matter) characteristics of soil., with data collected by handheld sensors in the field or samples collected for laboratory analysis

Question 74

Water

Answer 74

Examples of metrics include stormwater quantity (i.e., input and output) and quality (i.e., pollutants), with data collected by tools such as data loggers and automatic sensors

Question 75

Vegetation

Answer 75

Examples of metrics include growth rate, rooting depth, nutrient levels and presence of disease/pests, with data collected using tools such as biomass density index (BDI) and field measurements

Question 76

Society and Culture

Answer 76

Examples of metrics include comfort, perceptions of safety and accessibility, with data collected by post-occupancy evaluations, interviews and surveys

Question 77

Economics

Answer 77

Examples of metrics include revenue generation and cost savings, with data collected by tools such as GIS and public data, as well as surveys

Question 78

Post-Occupancy Evaluation

Answer 78

are used to determine if the built design meets the needs of the owner and site users. As such, the POE can provide the design team with valuable feedback and help them understand what aspects of their design were successful, how well the project meets the needs of its users and what aspects could be improved in the future, as well as providing data and conclusions that can be applied to design guidelines.

Question 79

Integrated Pest Management

Answer 79

is an “ecosystem-based strategy that focuses on long-term prevention of pests or their damage through a combination of techniques such as biological control, habitat manipulation, modification of cultural practices, and use of resistant varieties. Pest control materials are selected and applied in a manner that minimizes risks to human health, beneficial and nontarget organisms, and the environment”

Question 80

Greywater

Answer 80

water from showers, bath tubs, washing machines, and bathroom sinks, and it can be diverted away from the sewer system and reused in landscape irrigation, as well as to facilitate groundwater recharge.

Question 81

Blackwater

Answer 81

water from toilets and urinals that contains human waste and pathogens and cannot be reused without being treated. As such, it must be kept separate from any greywater systems