Advantages nd Disadvantages of a Parking Lot

In most countries where cars are the dominant mode of transportation, parking lots are a feature of every city and suburban area. Shopping malls, sports stadiums, megachurches and similar venues often feature parking lots of immense area.


The usual parking lot is paved with asphalt. Some are paved with concrete. Many are gravel lots. A few of the newer lots are surfaced with permeable paving materials.

Parking lots have their own special type of engineering. While parking lots have traditionally been an overlooked element of development projects by governmental oversight, the recent trend has been to provide regulations for the configuration and spacing of parking lots, their landscaping, and drainage and pollution abatement issues.

Parking lots can be small, with just parking spaces for a few vehicles, very large with spaces for thousands of vehicles, or any size in between. Small parking lots are usually near buildings for small businesses or a few apartments, although many other locations are possible. Larger parking lots can be for larger businesses or those with many customers, institutions such as schools, churches, offices, or hospitals, museums or other tourist attractions, rest areas, strip malls, or larger apartment buildings.

Some such businesse, institutions, or other building may have several parking lots if a single large lot cannot accommodate their parking needs. Large and very large parking fields can be for stadiums, airports, malls or shopping centers with multiple businesses, large schools or universities, convention centers or fair grounds, theaters, workplaces with many employees such as factories, plants, etc., or other large institutions. Often several businesses, offices, apartment buildings, or other institutions may use one or more parking lots in common for their convenience.

At places where most visitors and employees use their car to access place, the parking lot usually takes up more land area than the buildings. This is at least true for shopping centres and office buildings, unless a multi-storey park is used.

Parking lots near businesses, buildings, or institutions are often implicitly understood or explicitly labelled to be for the use of their respective customers or visitors, often with special vehicle spaces for the owners and employees. Parking lots around apartment buildings are often exclusively intended for parking use of their residents, although sometimes separate spaces may be provided for visitors. Such parking for businesses, offices, and residences is often free to the customers, patrons, or residents.

In most cases, especially in areas where parking is scarce, one must pay to park in a parking lot. Entry and exit access is often controlled at these type of lots to ensure those parking pay the required fee. The types of products used to enforce payment are called access controls. Automated payment, entry and exit systems can reduce the need for employees and can reduce payment losses. One way traffic spikes (tiger teeth), automated gates and tire spikes, and signage contribute to control of a fee-based parking lot. Examples of these products can be seen at Tiger Teeth Tire Shredders.[1]

In many congested areas where some businesses lack their own parking areas, there are parking lots where practically any driver can pay a fee to park. These types of parking lots are often effectively businesses in themselves. Some parking lots have parking meters into which coins must be paid to park in the adjacent space.

Some spaces in a parking lot may be marked as "reserved" for certain people, including those who are handicapped. There are often one or more parking spaces for handicapped people, which may be slightly wider, close to the point of entry for the corresponding store or building. Vehicles with handicapped tags may park there, but the non-handicapped are not allowed to.

Although many parking lots are rectangularly-shaped, there are parking lots of all sorts of shapes. A parking lot can be in front or back, on the side of the building it services, or any combination of these, including all around the building, often depending on local building codes. In a very large parking field, it is easy to get lost or have trouble finding one's vehicle. Such large parking lots often have various sections marked, for example by numbers or letters, to help identify the location.

The area in parking lots is organized into parking spaces, which are generally marked with paint lines for each vehicle and driving lanes in between so that vehicles can drive into and out of the spaces. The arrangement of the parking spaces relative to the driving lanes can feature perpendicular parking spaces, angle parking or parallel parking or possibly some combination of these.

Large parking lots have multiple lanes with rows of parking spaces between each one. Except for rather small lots, the location of the parking spaces for each vehicle are usually indicated with pavement markings or lines, similar to center lines on streets. A very common arrangement in large parking lots is angle parking for two rows of vehicles between driving lanes, with the parked vehicles facing front to front between the two rows. At the sides of the parking lot, other driving lanes connect these lanes perpendicularly so that a vehicle can drive into and out of the parking lot at designated locations.



Diagram of example parking lot layout with angle parking as seen from above. White arrows show direction of allowed travel in each lane (for right-hand-drive countries; vice versa in left-hand-drive countries). Several parking spaces closest to the building entrance are reserved for the handicapped. Cars of various colors are shown parked in some of the spaces. The obtusely pointed end indicates the front end of each car.

There may be speed limits, stop signs and crosswalks for pedestrians in large parking lots. Tall overhead lights may illuminate some parking lots at night.

Most spaces in normal parking lots available to the public are sized for vehicles about the size of a car. The spaces are usually arranged assuming the vehicle can back out of the parking space. In many rest areas on highways, long parking spaces are also available for trucks or other vehicles with trailers, into which they can enter at one end and leave at the opposite end to avoid potentially cumbersome reverse driving.

A common arrangement in paid parking lots is to have a vehicle entry point with a cross gate where an entering driver presses a button to take a stub with the entry time and to open the cross gate for access to the lot. When leaving, the driver would pay at an exit point according to how much time was spent in the lot as determined from the stub.

In order to keep unauthorized people from parking in lots, towing crews sometimes patrol parking lots after business closing hours, especially at night, to tow away vehicles which should not be parked there. After snowfalls in winter, vehicles with snow plows often clear snow from parking lots, usually after business closing hours and often during the night.

In response the worldwide intelligent transport system initiative, Parking Guidance and Information systems have been developed for use in urban areas. These systems use variable-message signs to direct drivers to car parks with available spaces.

Many drivers prefer underground car parking over outdoor parking because it prevents the inside of the car from heating up on hot or sunny days and it also prevents the car from being wet on rainy days.

Much of the above discussion also applies to large parking garages and multi-level parking areas.

Many businesses hire parking lot striping companies to stripe their lot. There are a wide variety of striping businesses. There are imprinting companies, striping companies, paving companies and other. They are most commonly hired for maintenance and rehabilitation of older lots.

Environmental considerations

Water pollution

Parking lots tend to be sources of water pollution because of their extensive impervious surfaces. Virtually all of the rain (minus evaporation) that falls becomes urban runoff. To avoid flooding and unsafe driving conditions, the lots are built to effectively channel and collect runoff.[2] Parking lots, along with roads, are often the principal source of water pollution in urban areas.[3]

Motor vehicles are a constant source of pollutants, the most significant being gasoline, motor oil, polycyclic aromatic hydrocarbons (PAHs), and heavy metals. (PAHs are found in combustion byproducts of gasoline, as well as in asphalt and coal tar-based sealants used to maintain parking lots.) Many parking lots are also significant sources of trash which ends up in waterways.[4]

Treatment of parking lot pollution : Traditionally, the runoff has been shunted directly into storm sewers, streams, dry wells or even sanitary sewers. However, most larger municipalities now require construction of stormwater management facilities for new lots. Typical facilities include retention basins, infiltration basins and percolation trenches.[5] Some newer designs include bioretention systems, which use plants more extensively to absorb and filter pollutants. However, most existing lots have limited or no facilities to control runoff.

Alternative paving materials : An alternative solution today is to use permeable paving surfaces, such as brick, pervious concrete, stone, special paving blocks, or tire-tread woven mats. These materials allow rain to soak into the ground through the spaces inherent in the parking lot surface. The ground then may become contaminated in the surface of the parking lot, but this tends to stay in a small area of ground, which effectively filters water before it seeps away. This can however create problems if contaminants seep into groundwater, especially where there is groundwater abstraction 'downstream' for potable water supply.

Landscaping

Many areas today also require minimum landscaping in parking lots. This usually principally means the planting of trees to provide shade. Customers have long preferred shaded parking spaces in the summer, but parking lot providers have long been antagonistic to planting trees because of the extra cost of cleaning the parking lot.

However, parking lots represent significant heat islands and, indeed, heat sinks in urban areas. The heat from paved areas in urban zones has been shown to even have the power to change the weather locally. By providing trees or other means of shading parking lots, the heat and glare resulting from them can be significantly reduced.[citation needed]

Services

Some parking lots have charging stations for battery vehicles. Some regions with especially cold winters provide electricity at most parking spots for engine block heaters, as antifreeze may be inadequate to prevent freezing.

Payment

Various forms of technology are used to charge motorists for the use of a parking lot.

Boom gates are used in many parking lots. A customer arrives to the entry ticket machine by vehicle, presses the ticket request push button, takes a ticket and enters the car park via the now raised barrier. To exit the parking lot, the customer presents the ticket to a cashier in a booth at the exit and tenders payment, after which the cashier opens the boom gate. More modern system users automatic pay stations, where the driver presents the ticket and pays the fee required before returning to their car, then drives to the exit terminal and presents the ticket. If the ticket has not been paid for, the boom barrier will not raise and will force the customer to either press the intercom and speak to a staff member, or reverse out to pay at the pay station or cashier booth.

Another variant of payment has motorists paying an attendant on entry to the lot, with the way out guarded by a one-way spike strip that will only allow cars to exit.

Parking meters can also be used, with motorists paying for the time required for the bay they are parked in.

Other parking lots operate on a pay and display system, where a ticket is purchased from a ticket machine, and then placed on the dashboard of the car. Parking enforcement officers patrol the parking lot to ensure compliance with the requirement.



BY HARSH