Trip-generation characteristics for convenience stores

Institute of Transportation Engineers. ITE Journal, Aug 2001 by Johnson, Kevin L, Hammond, Matthew I

THIS STUDY FOUND TRIP-- GENERATION RATES SIGNIFICANTLY DIFFERENT THAN ITE'S TRIP GENERATION, SIXTH EDITION RATES FOR THE CONVENIENCE STORE WITH GASOLINE PUMPS CATEGORY DURING THE PEAK HOURS, PLUS SIGNIFICANTLY HIGHER PASS-BY-TRIP PERCENTAGES. AS A RESULT, THE AUTHORS SUGGEST CONSIDERATION OF A NEW LAND USE CODE.

TODAY'S NEW CONVENIENCE stores have raised issues regarding trip generation and site usage compared to the characteristics of traditional convenience stores constructed between the late 1970s and the early 1990s. Some of the issues related to these new convenience stores often expressed by developers, local municipalities and state departments of transportation are:

How many vehicle trips will be generated in the a.m. and p.m. peak hours based on gross floor area (GFA) or fueling positions?

What percentage of the convenience store's vehicle trips is defined as 11 new trips" to the area during the a.m. and p.m. peak hours?

What percentage of customers will utilize the different services provided in each convenience store?

This study addresses these questions to accurately portray the trip-generation and site-usage characteristics of these new developments.

HISTORY OF THE CONVENIENCE STORE

The convenience store industry has changed in many ways throughout the years. In the past, the typical convenience store was a stand-alone facility ranging in size from 2,500 square feet (sq. ft.) to 3,500 sq. ft., offering convenience type items (i.e., tobacco, snack foods, beverages and pre-made foods). Some of these smaller facilities also contained four or fewer gasoline dispensers. Today's convenience stores maintain these same convenience products, but the stores are substantially larger, offering customers additional services and meeting requirements of the Americans with Disabilities Act (ADA). Thus the birth of the modern convenience stores. Unlike the existing convenience stores, these modern convenience stores are typically two to three times larger (between 4,500 sq. ft. and 7,500 sq. ft. of GFA). In addition, these convenience stores average twice as many fueling positions (ranging from 12 to 20). Unlike most of the Co-Branded and 7Eleven type convenience stores, these modern convenience stores offer madeto-order sandwiches, a deli counter and no-fee ATM machines. In addition to expanded produce and dairy sections, the new stores also offer ADA-compliant public restrooms, a dedicated manager's office, an employee break room, internal trash storage, and enlarged dry and refrigerated storage facilities. These convenience stores often create concerns regarding the prospective traffic impact they could create.

HISTORICAL STUDIES OF CONVENIENCE-STORE TRIP-- GENERATION CHARACTERISTICS

A traffic impact study (TIS) evaluates the number of trips generated by a site and the impact of the resulting traffic increase on the local roadway network. The characteristics of any development are important to engineers, transportation planners, local agencies, state departments of transportation and the public when estimating the affect these developments will have in a certain study area. Traditionally, the latest edition of the Institute of Transportation Engineers' (ITE) Trip Generation) is utilized to determine how many trips a particular development will generate. While Land Use Code 853 is contained in Trip Generation for a Convenience Store with Gasoline Pumps, the sites studied to develop the rates and equations contained in Trip Generation are significantly different from the larger convenience stores being built today. Land Use Code 845 (Gasoline/Service Station with Convenience Market) was not considered in this study because the primary business of the convenience stores studied is the sale of convenience products, not the fueling of motor vehicles.

The average site studied in Trip Generation contained 3,000 sq. ft. and eight fueling positions. Only 2 of the 53 sites studied contained more than 4,500 sq. ft. of space with a maximum of 16 fueling positions. Both are substantially different from the conveniencestore sites being constructed today.

The objective of this research was to determine if the trip-generation characteristics of convenience stores are different than those for the older convenience stores with gasoline contained in Land Use Code 853 of Trip Generation. If determined to be different, a second objective of this research was to develop a database of trip-- generation characteristics and prepare such rates or equations that can be used for forecasting future trip-generation characteristics for similar convenience stores.

An additional publication, the Trip Generation Handbook,2 also contains information on pass-by-trip characteristics. "Pass-by trips are trips that are attracted from traffic passing the site on an adjacent road that offers direct access to the generator."2 Most of the a.m. and p.m. peak-hour pass-by data in the Trip Generation Handbook were collected from sites in Florida, Indiana and Kentucky in 1993. An objective of the research study was to determine if the pass-by-trip characteristics of the smaller convenience stores with gasoline were also applicable to the new, larger convenience stores.