Module 3: Road and Traffic Considerations Flashcards
Purpose of road?
Primarily a function of the immediate land use
Provide connections to locations outside of immediate area
Road classifications?
Local
Street providing land access with little or no provision for through traffic
Design speed of 40km/h
Low density areas
Generally lower density areas, stop signs, parked cars, kids
10% absolute maximum grade
Pavement structure varies across municipalities, within them; look at successfully existing adjacent pavement structures
Low quality materials in aggregate standards due to scarcity of resources, unless near a good source
No good common standard for wheelchair ramps
Collector
Performs dual function of land access and distribution of traffic between local and arterial streets
1000-12,000 daily volume
Design speed of 60km/h
Medium and high density areas
12% absolute maximum grade
Pavement structure varies across municipalities, within them; look at successfully existing adjacent pavement structures
Low quality materials in aggregate standards due to scarcity of resources, unless near a good source
No good common standard for wheelchair ramps
Arterial
Provides continuous route primarily for through traffic with land across a secondary consideration
5000-30,000 daily volume
15% absolute maximum grade
Pavement structure varies across municipalities, within them; look at successfully existing adjacent pavement structures
Low quality materials in aggregate standards due to scarcity of resources, unless near a good source
No good common standard for wheelchair ramps
There are others, but not important here (possibly forest service?)
18% absolute maximum grade?
Pavement structure varies across municipalities, within them; look at successfully existing adjacent pavement structures
Low quality materials in aggregate standards due to scarcity of resources, unless near a good source
No good common standard for wheelchair ramps
Road and right-of-way widths? Determined by?
Determined by density
Low: <16 dwellings/ha
Medium: 16-30 dwellings/ha
High: >30 dwellings/ha
More dense = more wide
Greater land slope = more wide right-of-way for local streets
No less than 20m for right-of-way (roads are actually less wide)
However, there have been provisions made in standards for right-of-ways widths less than 20m
see https://docs.google.com/document/d/13QjXslbKcm56KCcnbQaC6OebBPX7u248o9cNfhDDHKQ/edit
remember: local roads in hillside locations (so that means greater slope) will need wider SRW
What generally governs absolute maximum grade in BC? Why will they have to be increasingly used in the future?
Snowfall, heavy snowfall
Due to the Agricultural Land Reserve (ALR), more housing will be developed on hillsides
2 types of storm drainage design. they consist of?
conventional method
storm water management method
Substantial amount of engineering design work for each development proposal and formulation by the municipality of overall watershed design criteria
consist of
They should consist of a minor system component and a major system component (both)
Needed because there is increasing exposure to flooding
Water Distribution: main and service connection location? Hydrants? How are hydrants standardized?
Main and service connection location
Must be separate from sanitary sewer mains and service connections (Ministry of Health and Environment)
Saves costs
Hydrants
3-4 hydrant types
80% produced by Vancouver company
Variety of municipal specifications
Sliding gate vs compression type
Type of pumper connection
Main spindle rotation
Municipalities try to standardize hydrants by
Manufacture
Type
Pumper connection
Spindle rotation
Who sets out the standards of right-of-way and pavement widths? What do the standards include?
Transportation Association of Canada
Widths, geometric design standards, coding for road standards
What ultimately governs design? What plays a large role? What must be reduced?
Its use
Its purpose, with a minimum of disruption and waste
Road must be built to serve its purpose
Engineering knowledge and judgement is needed in preparing transportation and land use plans
Must reduce dislocation of people and business
Traffic factors that can be anticipated based on a good plan?
Traffic volume
Vehicular type (truch, bus, car)
Trip type (commuter, local, through, shopping, sightseeing, recreational)
Public transportation needs (future traffic protection)
Functional classifications of road
Rural
Freeway
Arterial
Collector
local
Urban
Freeway
Arterial
Collector
Local
Remember: rural and urban refer to the predominant characteristics of adjacent land use, NOT jurisdictional boundaries
see https://docs.google.com/document/d/13QjXslbKcm56KCcnbQaC6OebBPX7u248o9cNfhDDHKQ/edit
describe freeways
Heavy volume
High speeds (80-100km)
Free flowing conditions
Long trip traffic
8000 - 20000 (rural to urban)
limited access roads
opposing traffic lanes seperated
overpasses and bridges
restrictions on parking, pedestrains and cycling
connects to freeways, arterials and collectors only
describe arterials; primary functions
major routes in networks
connect industrial and commercial centres, concentrations of residential development
use arterials if freeways are not warranted
1000 - 12000, 500-30000 daily users (rural - urban)
usually uninterrupted flow; controlled intersections
public transportation loading zones, turning lanes
restricted parking
50-90km
connect to all other road types, even local, industrial or commercial
describe collector streets; primary function
Collect traffic from local roads and distribute it to other local roads, arterials, sometimes freeways
Service land, permitted full access to adjacent land usually
200-5000, 1000-12000 (rural - urban)
flow interrupted by stop conditions at intersections and turning movements at land access points
connect to all other road types, usually not freeways in urban settings; rarely found in central business districts
describe local streets; primary function
provide land access
Trips on local roads have their origin or destination within the length of the road
interrupted flow
20-50-80km
mostly passenger vehicles or light service trucking
connect to arterials, collectors, locals; only collectors and locals in urban setting
Preliminary and Secondary Groups
Some jurisdictions divide the major classification into primary or secondary
Secondary urban local
A short crescent or cul de sac
Primary urban collector
A collector serving primarily industrial area
Extra width and strength needed to handle trucking
What are the design elements for each basic classification of road?
Determine physical limitations of the route
Know anticipated traffic
