Parking Lot Design Civil Engineering and Architecture © 2010 Project Lead The Way, Inc.

TABLE OF CONTENTS Ingress and Egress Number of Parking Spaces Size of Parking Spaces Accessibility Aisle Width Pedestrian Circulation Special Vehicle Access Off-Street Loading Area Waste Disposal Drainage Landscaping Lighting

Ingress and Egress The means of entering and leaving the site Regulated by state and local governments Width Slope Drive radius Pavement composition Encroachment permit People and vehicles must be able to enter and exit your project site, but the access should be controlled. The number and size of entrances and exits must be carefully planned to reduce the conflict between the street traffic and traffic accessing the site. State and local governments regulate access to public roadways and often enforce restrictions on the width, slope, radius, and pavement composition of the access road. Regulations may also require a commitment to perform alterations to the public road (such as adding turn lanes, street lights, and pavement markings) before access roads can be built. Permits, called encroachment permits, are often required in order to connect a roadway to a public road.

Ingress and Egress Discourage through traffic Rule of thumb Less than 5000 vehicles/day use single 2- way drive or two 1-way drives Align new drives with other access drives Local regulations Distance from corners and other drives When planning entrance and exit drives, try to discourage through traffic to minimize traffic. A good rule of thumb is that if the property will have less than 5000 vehicle visit each day, use only one 2-way or two 1-ways drives. Local and state regulations will often specify design specifications such as the distance to street intersections and other drives. In general, locate drives as far away from street intersections and other driveways as possible. Nearby intersections can increase the likelihood of car accidents at the driveway.

Number of Parking Spaces Dictated by local codes Dependent upon use of the building Example requirements ©iStockphoto.com

Size of Parking Spaces Parallel Ninety-degree Angled Most difficult to access Avoid if possible Ninety-degree Most spaces per area Typical size: 9 ft x 18 ft or 19 ft More difficult to access than angles Not recommended for short term parking Angled Size varies according to angle 60 degree parking most common

Accessibility Accessible parking required Per the Americans with Disabilities Act and Architectural Barriers Act Guidelines, every facility must provide at least the number of accessible parking spaces indicated by this table.

Accessibility Size of accessible parking spaces Accessible car spaces must be at least 96 inches wide, and accessible van spaces must be at least 132 inches wide. Each accessible space must be adjacent to a 60 inch wide aisle on an accessible route to the building.

Accessibility Size of accessible parking spaces Accessible car spaces must be at least 96 inches wide, and accessible van spaces must be at least 132 inches wide. Each accessible space must be adjacent to a 60 inch wide aisle on an accessible route to the building. ADA ABA Accessibility Guidelines

Aisle Width Dictated by local codes Two-way aisle is preferable Typical two-way aisle is 24 feet wide May be less for one-way traffic Accessible car spaces must be at least 96 inches wide, and accessible van spaces must be at least 132 inches wide. Each accessible space must be adjacent to a 60 inch wide aisle on an accessible route to the building. ©iStockphoto.com

Pedestrian Circulation Separate pedestrians from traffic Provide accessible route to entrance from parking, public transportation, and adjacent buildings Typical walkway widths 3 ft wide for one-way 5 ft wide for two-way The lower right picture shows a pedestrian barrier which can improve pedestrian safety. ©iStockphoto.com US. Department of Transportation Federal Highway Administration

Pedestrian Circulation Align parking spaces for easy pedestrian movement It is preferable to align parking spaces so that pedestrians walking to the building from the parking lot will walk along the aisles and not between parked cars. PREFERRED PERPENDICULAR ALIGNMNET PARALLEL ALIGNMNET TM 5-803, Site Planning and Design courtesy Department of the Army.

Special Vehicle Access Plan for access for special vehicles that may access the site Fire engines City buses School buses Tractor trailers Garbage trucks Research required road widths, turn radii, and parking It is preferable to align parking spaces so that pedestrians walking to the building from the parking lot will walk along the aisles and not between parked cars. ©iStockphoto.com

Off-Street Loading Area Plan for access for loading and unloading of products and materials Best practices Locate loading area away from traffic Locate loading area out of view Check local requirements Most commercial facilities receive shipped packages. Local regulations may require that off-street loading areas be provided. If you need to provide off-street loading, you will probably want to locate the loading area(s) away from vehicular and pedestrian traffic and out of view of public roads and customers. ©iStockphoto.com

Waste Disposal Plan for dumpster and garbage truck access Best practice – Screen dumpster from view Fence Wall Landscaping Check local regulations Most commercial facilities will need to provide an area for required dumpsters and adequate access for the waste disposal trucks. Because waste disposal facilities can be unsightly, local regulations often require some type of screening which can include a fence or wall and landscaping. ©iStockphoto.com

Drainage Traditional design slopes pavement toward storm drains LID techniques Reduce impervious surface area Permeable pavement Permeable paver blocks Drain to adjacent buffers, strips, and swales Drain to nearby bioretention areas Since parking areas are typically impervious, they typically generate a large volume of storm water runoff. This storm water must often be managed on-site. Some of the LID techniques that we discussed earlier can be used to decrease storm water volume and increase the quality of the storm water as it slowly migrates back into the water system. We will discuss methods to handle large volumes of storm water later. Courtesy the Environmental Protection Agency

Landscaping Improves aesthetics Building base landscaping Provides shade Parking screen (buffer) Parking islands Landscape design, like all aspects of a building project, will be controlled by rules and regulations. Because parking lots often have a negative visual impact, many municipalities have adopted regulations that require efforts to reduce the negative impact. Landscaping is often specified to screen the parking lot from adjacent streets and properties and is often called a buffer. Codes often require landscaping within a parking lot to break up the expanse of pavement. These areas are called parking islands. Landscaping is often required at the base of the building between the parking area and the building to provide a visual break between the pavement and the building so that the pavement does not continue up to the building wall. ©iStockphoto.com

Lighting Improves safety Often required by local regulations Provides light to illuminate property but does not illuminate adjacent property ©iStockphoto.com

Example Locate the following on this commercial site plan. Ingress/Egress. How many entrances/exits are planned? [2] (click to locate on plan) Is the aisle one-way or two-way? [two-way] How can you tell? [arrow on pavement] (click to find arrows) What is the aisle width? [24 ft] (click to see dimension) Parking Spaces. What type of spaces are provided? Parallel, angled or 90 degree? [90 degree] How big is the typical parking space? [9ft x 18ft] (click to indicate dimensions] Accessible Parking Spaces. How many accessible spaces are shown? [3] (click to indicate accessible spaces) Is there adequate pedestrian access? [yes, lots of sideways] How wide are the sidewalks? [5 ft or 6 ft] (click) Where is the waste disposal area? [south west corner of parking lot] (click to locate on plan) How big is the pad? [10 ft x 20 ft] What type of screen will block view of the dumpster? [wood dumpter enclosure] (click) How is drainage of the parking lot provided? [parking pavement sloped to storm drains and piped off site (to Cambridge Lake)] (click to indicate storm drains) Note that elevations of the pavement are given on Dwg C-3. Can you identify the use of any LID techniques? [permeable paving] (click to indicate notes)

TABLE OF CONTENTS Ingress and Egress Number of Parking Spaces Size of Parking Spaces Accessibility Aisle Width Pedestrian Circulation Special Vehicle Access Off-Street Loading Area Waste Disposal Drainage Landscaping Lighting

Image Sources Istockphoto. (2009). Retrieved December 15, 2009, from www.istockphoto.com Environmental Protection Agency. (n.d.). Stormwater management best practices. Retrieved December 15, 2009, from http://www.epa.gov/greeningepa/stormwater/best_practices.ht m#permeablepavers Architectural and Transportation Barriers Compliance Board. (2004) ADA and ABA accessibility guidelines for buildings and facilities. Retrieved November 20, 2009, from http://www.access- board.gov/ada-aba/preamble.htm U.S. Department of Transportation, Federal Highway Administration. (n.d.) Flexibility in highway design. Retrieved December 15, 2009, from http://www.fhwa.dot.gov/environment/flex/ch03.htm