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From page 1...
... 18-1 18 -- Parking Management and Supply OVERVIEW AND SUMMARY This "Parking Management and Supply" chapter presents information on how travelers respond to differences in the supply and availability of vehicle parking, including changes that might occur as a result of shifting land use patterns, alterations of regulatory policy, or attempts to "manage" the supply of parking. Information on "normal" baseline parking characteristics is also provided.
From page 2...
... 18-2 Effects of parking supply availability and management are often hard to separate from those associated with parking fees and pricing. In addition, parking supply management is frequently implemented in circumstances where other factors are changing or being changed.
From page 3...
... 18-3 Communities may elect to provide off-street parking at the fringe, or periphery, of a central business district (CBD) or activity center, with the aim of intercepting private vehicle trips before they enter a congested downtown street network.
From page 4...
... 18-4 On-Street Commercial Area Parking Management. Communities may impose parking restrictions to prohibit on-street parking or limit its duration.
From page 5...
... 18-5 The intrinsic relationship between supply and pricing makes it is difficult to discern their individual effects. Parking supply is generally limited where land use is intense and costs of land are high.
From page 6...
... 18-6 exceed typical utilization, with peak occupancy rate averages from five studies ranging from 1.2 to 2.8 parked vehicles per 1,000 square feet, with an average of 2.2 and a median of 2.4. This demand represents some 50 to 80 percent of supply in the four studies with supply data.
From page 7...
... 18-7 problem of a declining parking ratio built into its tenant lease by introducing a fee/subsidy arrangement coupled with priority HOV parking that resulted in an SOV share of 54 percent. The City of Bellevue implemented space rationing and pricing at its City Hall location that produced an SOV share of 52 percent.
From page 8...
... 18-8 RESPONSE BY TYPE OF STRATEGY Maximum and Minimum Parking Requirements The most common regulatory mechanism through which parking supply is controlled is zoning or building codes that specify minimum (or sometimes maximum) parking ratios.
From page 9...
... 18-9 building occupancy, equating to an average of 52 percent of parking capacity at a theoretical 95 percent building occupancy. The corresponding rate of parking demand ranged from 2.0 to 2.3 vehicles per 1,000 occupied GSF, with the average nearly midway (Willson, 1992)
From page 10...
... 18-10 While no information was given on the actual parking code requirements for the sites studied by ULI, the amount of parking provided ranged from a low of 1.2 spaces per 1,000 square feet of gross leaseable area (GLA) to a high of 5.8 for a small new business park located in the west.
From page 11...
... 18-11 bonuses in exchange for building fewer on-site parking spaces. Concurrently, Montgomery County, as part of its APFO requirements, imposes traffic level of service thresholds on development in the more densely settled areas of the county.
From page 12...
... 18-12 This is strong indication of declining transit mode shares. What has apparently happened is that developers, while opting to locate buildings inside the SPID zones and often taking advantage of the freedom to construct higher buildings, have not responded to the parking requirement relief.
From page 13...
... 18-13 Table 18-2 Experiences of Six Cities with Managing Parking Ratios, Circa 1988 City Downtown Employment (Population) Parking Supply CBD Parking Rates CBD Parking Policy CBD Traffic Mitigation Key Findings Portland, OR 90,000 (Portland 380,000)
From page 14...
... 18-14 Table 18-2 Experiences of Six Cities with Managing Parking Ratios, Circa 1988 (continued) City Downtown Employment (Population)
From page 15...
... 18-15 Portland. The city of Portland, Oregon, has for years used parking supply management as a major strategy to achieve transportation and development goals.
From page 16...
... 18-16 with 10,000 of them outside the official downtown. No parking is "required" by code in the downtown (C-3)
From page 17...
... 18-17 have not taken advantage of the possibilities for parking reduction, and in fact, have tended to provide more than the minimum required parking (Higgins, 1989)
From page 18...
... 18-18 Figure 18-1 Relationship between downtown parking spaces per employee ratios and transit mode share for Canadian cities Source: Plot of data presented in Morrall and Bolger (1996)
From page 19...
... 18-19 one-variable model presented above, the estimated parameters for both variables are statistically significant (Morrall and Bolger, 1996) , and the constant is a little smaller.
From page 20...
... 18-20 Response Factors," all in Chapter 13. In Chapter 19, "Employer and Institutional TDM Strategies," other types of workplace strategies are covered.
From page 21...
... 18-21 overall. Example multifaceted programs are covered in the case studies "NRC Site Parking Management -- Montgomery County, Maryland" in this chapter, and "City Hall Employee TDM -- Bellevue, Washington," in Chapter 19, "Employer and Institutional TDM Strategies." Workplace Park ing Supply Management Overa ll A difficulty in assessing most documented cases of employer parking management is that the parking supply issues or strategies are tied in with numerous other factors or strategies, including transit subsidies, guaranteed ride home, or other alternative mode incentives.
From page 22...
... 18-22 site vehicle trip rate and the CTPP-based ambient trip rate was used as an indicator of the respective TDM program's effectiveness in reducing vehicle use by employees (Comsis, 1994)
From page 23...
... 18-23 • "Incentive and Disincentive" programs, where financial subsidies and/or parking charges are used to encourage use of alternative modes and discourage solo driving. • "Service and Incentive" programs, which combine the financial and service features of the previous two categories.
From page 24...
... 18-24 discourage solo driving or influence land use management. The following are key findings (KPMG, 1995)
From page 25...
... 18-25 On-Street Residential Neighborhood Parking Management Insufficient on-site parking, substantial parking fees, and even on-site parking management each may cause overflow of parking vehicles in search of empty, cheap, free, or easier to access spaces. On-street parking in residential areas is often the most adversely impacted.
From page 26...
... 18-26 Hermosa Beach, California. A residential permit parking demonstration in Hermosa Beach provides results in the context of a recreational destination with over-saturated summertime parking.
From page 27...
... 18-27 Table 18-7 Permit Area Resident Parking Behavior in Hermosa Beach, California Parking Use and Location Before Permit Program (1979) After Permit Program (1983)
From page 28...
... 18-28 Table 18-8 Parking and Transportation Characteristics at Six San Francisco Medical Institutions Medical Institution Davies SFGH St. Mary's Kaiser St.
From page 29...
... 18-29 Table 18-9 Correlation Between Employee SOV Rates and Contributing Factors Monthly Parking Cost On Street Parking Limit Transit Veh./Hr. Parking Spaces per Employee Percent Drive Alone Monthly Parking Cost 1.00 -0.74 0.76 0.04 -0.85 On Street Parking Limits -0.74 1.00 -0.61 -0.37 0.71 Transit Vehicles per Hour 0.76 -0.61 1.00 0.59 -0.60 Parking Spaces per Employee 0.04 -0.37 0.59 1.00 0.10 Percent Drive Alone -0.85 0.71 -0.60 0.10 1.00 Note: Correlation reflects the degree of relatedness between two variables where a correlation coefficient of 1.0 indicates that the two items are perfectly related, and 0.0 indicates no relationship.
From page 30...
... 18-30 Effective enforcement of curb parking is essential, especially where time limits are in place. In Boston, for example, 1972 field surveys found average parking durations of 70 minutes at meters with 30 minute limits, 90 minutes at 1 hour meters, and 135 minutes at 2 hour meters.
From page 31...
... 18-31 simply mean that longer time limits and SOV use are both more common in smaller cities with fewer incentives not to drive. A review of this information with the objective of determining the relative importance of parking supply versus on-street parking price in influencing travel demand is inconclusive.
From page 32...
... 18-32 most notably as a result of insufficient user cost savings to justify the loss in time or convenience relative to core area parking. There are several examples of areas that have had difficulty encouraging developer implementation of peripheral parking systems (K.T.
From page 33...
... 18-33 A number of CBD peripheral parking systems were implemented in the 1970s and early 1980s, many as demonstration projects. A summary of various sites as of 1981 is provided in Table 18-10.
From page 34...
... 18-34 the Superdome to the CBD. Of 5,000 spaces available, 85 percent were occupied on a typical day.
From page 35...
... 18-35 While Minnesota Rideshare never performed a formal occupancy count at the free lots, a review of the permit registration data indicated that the 1,207 pools registered in December 1988 claimed 2,752 named riders, equivalent to an average auto occupancy of 2.28 persons per vehicle (when carpooling)
From page 36...
... 18-36 UNDERLYING TRAVELER RESPONSE FACTORS The impact of parking supply management strategies on travel behavior, and thus their effectiveness in achieving desired objectives, depends on a variety of determinants. These factors relate to the application setting and context, to known attributes of traveler choice behavior, and to the time frame involved.
From page 37...
... 18-37 tipping the balance toward minimization of supply. These circumstances also may exist, though typically to a lesser degree, at certain non-downtown transit stations or stops.
From page 38...
... 18-38 and Fees," under "Response by Type of Strategy" -- "Changes in Overall Parking Rates" and in the case study "A Parking Tax in the City of San Francisco")
From page 39...
... 18-39 parking will tend to follow suit, to at least some degree, and prices are normally set sufficient to cover debt service requirements. Private employer parking is typically offered as a benefit to employees, subsidized by the employer.
From page 40...
... 18-40 Table 18-12 Urban Area, Modal Split, and Parking Characteristics for 17 U.S. CBDs Name of City New York, NY Pittsburgh, PA Philadelphia, PA San Francisco, CA Tempe, AZ Madison, WI Santa Barbara, CA Phoenix, AZ Metro Area Population 19,000,000 2,300,000 5,182,705 5,200,000 155,000 259,491 90,000 2,100,000 CBD Employment 1,020,424 140,000 287,869 198,000 7,700 28,850 27,900 25,000 Modal Split (Weekday Work Trips to CBD)
From page 41...
... 18-41 Table 18-12 Urban Area, Modal Split, and Parking Characteristics for 17 U.S. CBDs (continued)
From page 42...
... 18-42 Table 18-13 Selected Correlation Coefficients for Area Population, CBD Employment, Parking Supply, Parking Pricing, and Travel Mode Shares in 17 U.S. CBDs Factor Transit Share HOV Share SOV Share Parking Rates Metropolitan Area Population 0.87 0.01 -0.80 0.68 to 0.86 CBD Employment 0.85 0.00 -0.79 0.63 to 0.83 Total Spaces/1,000 Employees -0.49 0.02 0.39 -0.42 to -0.45 Monthly Off-Street Parking Rates City-owned facilities 0.89 0.18 -0.92 Non-city-owned facilities 0.82 0.31 -0.89 Percent Off-Street Parking Free -0.37 -0.55 0.40 Percent Owned by City -0.29 -0.60 0.49 Note: Correlation reflects the degree of relatedness between two variables where a correlation coefficient of 1.0 indicates that the two items are perfectly related, and 0.0 indicates no relationship.
From page 43...
... 18-43 though not quite as strong (r = -0.42 to -0.45) ; the fewer the parking spaces per 1,000 employees, the higher the price of parking to the user.
From page 44...
... 18-44 evaluations indicate a substantial tendency for change in parking location choice in the face of parking management actions (Feeney, 1989)
From page 45...
... 18-45 An illustration of the combined effect of time and cost savings in comparison to time loss and lesser savings is provided by a peripheral lot and shuttle service operated in Albany, New York, as a benefit to state employees. The operation was primarily in response to a long waiting list for parking spaces at state facilities.
From page 46...
... 18-46 Of course, businesses and households generally would not change location based entirely on issues related to parking supply. Workers will obviously choose jobs that provide them with the best opportunity, and employers will tend to locate where they have access to the pool of employees, services, contacts, and consumers they need.
From page 47...
... 18-47 Two spatial scenarios were simulated, one "fixed" where the spatial distribution of land use would not change under the influence of the ABC policy, and one "elastic" where it would change. Additionally, analyses were framed where parking enforcement would either be restrictive or lax, characterized as small overflow or large overflow of parking into adjacent zones (Hamerslag, Fricker and Van Beek, 1994)
From page 48...
... 18-48 unfortunately so does transit ridership, contrary to the objectives of the "ABC" location policy. The parking restrictions lead to a decentralization of employment centers, which, in the Netherlands, would favor greater use of walking and bicycles, but makes public transit less practical to provide or use.
From page 49...
... 18-49 RELATED INFORMATION AND IMPACTS Characteristics of Parking Demand The basic characteristics of parking demand, such as trip purpose, parking duration, daily turnover per space, vehicle accumulation, and walking distances incurred, provide important inputs to assessing and developing parking management actions. Full reports are devoted to this subject and associated parking facility design and operation issues.
From page 50...
... 18-50 Trip Purpose. A major determinant of parking characteristics is trip purpose.
From page 51...
... 18-51 It is not known to what extent smaller cities any longer exhibit the higher prevalence of shopping clearly reflected in the SR 125 data. The newest observations hint that the reverse condition may now hold, but the data is far too thin for any certainty.
From page 52...
... 18-52 Table 18-19 Trip Purpose Distribution and Average Auto Occupancies of CBD Parkers at Peak Accumulation in Portland, Oregon Trip Purpose Percentage at Peak Accumulation Auto Occupancy Home Based Work (HBW) 64% 1.22 Home Based Other (HBO)
From page 53...
... 18-53 Table 18-20 Length of Time Parked (Hours) in CBD Spaces Averaged by Trip Purpose City a Urbanized Area Population b Study Year(s)
From page 54...
... 18-54 The overall averages and the percentage distributions are subject to the same age-of-data issues raised above because changes in the mix of purposes, and thus the mix of short- and long-term parking, may affect overall averages and duration distributions. Reported average parking durations, especially for work trips and all trips, may also be affected by survey duration.
From page 55...
... 18-55 Additional data from the Boston 1972 survey highlights the association between curb parking, short duration, high turnover, and use of curb parking by non-work purpose trip makers. The percentage of non-work purpose trips utilizing parking in Boston was found to be 76.8 percent non-work for legal curb spaces, 40.7 percent for lots, and 46.7 percent for garages.
From page 56...
... 18-56 Note that Table 18-23 gives the number of spaces surveyed. Normally, other things being equal, a CBD survey covering a smaller number of spaces will exhibit a somewhat elevated turnover rate because of excluding observations outside the central core of highest parking demand.
From page 57...
... 18-57 Table 18-25 Peak CBD Parking Accumulation and Percentage of Parking Supply City a Urbanized Area Population b Study Year(s) c CBD Parking Supply Peak Parking Accumulation Percentage of Supply Needham Ctr., MA 29,000 1986 582 660 d 114% d Population Group 10,000-100,000 e 1960-68 3,760 2,120 56 Population Group 100,000-250,000 1960-68 7,710 5,740 74 Charlotte, NC 351,000 1987 29,900 20,701 69 Population Group 250,000-500,000 1960-68 12,300 8,780 71 Nashville, TN 518,000 1970 19,724 14,020 71 Tampa, FL 521,000 1983 20,841 17,740 85 Jacksonville, FL 598,000 1981 31,517 21,953 70 Rochester, NY 606,000 1977 22,231 16,935 76 Memphis, TN 775,000 1981 16,986 12,253 72 Population Group 500,000-1,000,000 1960-68 22,600 18,200 81 Portland, OR 1,050,000 1988 42,036 34,000 81 Milwaukee, WI 1,207,000 1972 30,707 28,142 92 Cleveland, OH 1,752,000 1978 53,912 39,700 74 Baltimore, MD 1,755,000 1989 38,636 31,129 83 Dallas, TX 2,451,000 1981 59,610 49,600 83 Boston, MA 2,679,000 1972 39,230 36,120 91 Population Group Over 1,000,000 1960-68 58,800 45,000 77 Note: a See Note "a," Table 18-17.
From page 58...
... 18-58 Table 18-26 CBD Ratio of Parkers in the Peak Accumulation to Total Daily Parkers by Trip Purpose Southern Cities a (circa 1960-65) Boston Study (1972 data)
From page 59...
... 18-59 Table 18-27 Average Distance Walked (Feet) from Parking Space to CBD Destination Classified by Trip Purpose City a Urbanized Area Population b Study Year(s)
From page 60...
... 18-60 Suburban Single-Use Park ing Suburban parking may be classified into parking associated with more or less stand-alone building/land uses (single-use parking) , and the parking associated with mixed land uses that has been specifically designed as shared parking.
From page 61...
... 18-61 Table 18-29 Summary of ITE Parking Demand Values for Individual Developments in Predominantly Negligible Transit Use Environments Spaces per Evaluation Unit a Use Evaluation Unit Day of Week Average 85th Percentile Industrial parks, manufacturing, and light industry 1,000 sq.
From page 62...
... 18-62 parking accumulation patterns to allow dual or multiple use of parking spaces. This synergy can work when the parking needs associated with two or more different land/building uses are at or near their peak at different times.
From page 63...
... 18-63 Table 18-30 Representative Hourly Parking Accumulations as Percentages of Peak Hour Parking Demand for Various Uses Residential Hotel Office Retail Restaurant Cinema Non-CBD CBD Guest Room Restaurant Conf.a Hour Week- day Sat.
From page 64...
... 18-64 The maximum weekday parking space demand is thus estimated to be 449 spaces, with the demand occurring at 2:00 PM. Using a similar approach, the estimated maximum Saturday demand would occur at 8:00 PM: 8:00 PM: 100 x 0.5 @ 20% = 10; 750 x 0.37 @ 100% = 278; Total = 288 spaces The weekday maximum parking demand thus governs at 449 spaces.
From page 65...
... 18-65 than the CBD all-sites value of 43 percent in Table 18-31. Portland parkers identifying nonwork purposes as their reason for a downtown trip reported 1.82 places visited on average (TDA Inc., 1988)
From page 66...
... 18-66 Table 18-32 Test Calculations of Mixed Use Parking Requirements with Comparisons to Actual Observed Parking Accumulation Type of Mixed-Use Project a Typical Zoning Parking Space Require -ment b Individual Use Estimate of Peak Demand Shared Parking Estimate of Peak Demand Spaces Saved Relative to Individual Use Est.c Percent of Parking Spaces Saved c Actual Peak Parking Accumulation d % Overestimate for Individual Use Estimate % Overestimate for Shared Parking Estimate Office/Retail 5,858 5,749 5,229 520 e 9% e 5,570 3% -6% Office/Retail 3,744 2,936 2,788 148 5% 2,352 25% 19% Office/Retail 900 772 617 155 e 20% e 633 22% -3% Office/Retail 3,048 2,814 2,291 523 e 19% e 2,592 9% -12% Office/Retail 196 162 154 8 5% 154 5% 0% Office/Entertainment 1,879 1,458 1,326 132 9% 1,163 25% 14% Office/Entertainment 1,016 812 714 98 12% 464 75% 54% Office/Entertainment 2,112 1,724 1,501 223 13% 614 181% 144% Office/Hotel 1,399 1,145 1,006 139 12% 882 30% 14% Office/Hotel 1,346 1,125 743 382 34% 594 f 89% f 25% f Office/Hotel/Entertainment 1,933 1,627 1,323 304 19% 725 f 124% f 82% f Office/Hotel/Entertainment 1,452 1,236 990 246 20% 525 f 135% f 89% f Office/Hotel/Entertainment 862 784 659 125 e 16% e 809 -3% -19% Office/Hotel/Entertainment 3,188 2,588 2,183 405 16% 1,498 f 73% f 46% f Office/Retail/Hotel/ Entertainment 9,610 8,316 4,242 4,074 49% 2,287 f 264% f 85% f Office/Retail/Entertainment 1,094 869 754 115 13% 600 45% 26% Office/Retail/Entertainment 5,157 5,099 3,755 1,344 26% 2,869 f 78% f 31% f Notes: a Nationwide sample of projects. b Office = 4.0 spaces per 1,000 sq.
From page 67...
... 18-67 Travel Choices After Parking Supply Modification The only empirical information available on mode or other travel choice outcomes for nonwork travel, in response to parking supply modification, appears to be whatever can be inferred from a few measured responses to applications involving a mix of travel purposes. An example is the Eugene, Oregon, on-street parking management demonstration, covered under "Response by Type of Strategy" -- "On-Street Residential Neighborhood Parking Management" -- "Effects on Curb Parking Behavior." That demonstration, like some others of its type, encountered a primary response of change in parking behavior rather than mode choice behavior.
From page 68...
... 18-68 Table 18-33 Mode Shares and "With" and "Without" Vehicle Trip Rates for Multifaceted TDM Programs Emphasizing Parking Supply Management Employee Commute Mode Shares with TDM Program Vehicle Trip Rate per capita a Case Study (Handbook Chapter) Drive Alone Carpool Vanpool Transit Other With Without b Difference US WEST Parking Pricing and Management – Bellevue, WA (13)
From page 69...
... 18-69 Table 18-34 Mode of a Week's Work Trips in The Hague Before and After Closure of the Parking Lot Previously Used Commute Mode Trips Before Mode Share Trips After Mode Share Percent Change Auto Driver 386 91% 312 74% - 19% Auto Passenger 0 0% 15 4% + … Transit 22 5% 80 19% + 265% Moped/Bike 15 4% 17 4% + 13% Walk 1 <1% 0 0% - … No Trip that Day 41 n/a 41 n/a no change Total 465 100% 465 100% Note: Includes only users of the affected parking lot; not all central area parkers or commuters. Source: Gantvoort (1984)
From page 70...
... 18-70 Code Requirement Implications The decision by a developer on how much parking to provide, and whether that parking will be in surface or structured facilities, depends heavily on local building and zoning codes. Since these codes normally stipulate a minimum ratio of on-site parking spaces to leasable floor area, the developer's decision is whether to meet or exceed the minimum requirement.
From page 71...
... 18-71 For a parking facility to "break even," its revenues must equal or exceed the amortized annual costs of developing and operating the facility. Various studies have estimated the required break-even revenues per space.
From page 72...
... 18-72 The TCRP Report 35 authors note that while these costs are generic and are based on a set of assumptions constant across all three parking types, the high and low figures depict national averages, and actual values would depend on a particular project. In dense urban areas, for example, with limited vacant land, land costs may be far in excess of the averages shown (Cambridge Systematics, 1998)
From page 73...
... 18-73 A significant investment in employer parking capacity currently exists in the United States. The previously mentioned 1995 national survey of such parking estimated that 83.7 percent of the spaces in employer-owned facilities for employees, visitors, etc.
From page 74...
... 18-74 Critical Aspects of Parking Supply Management Parking supply management is especially subject to extensive governmental intervention, particularly at a micro-scale. This control makes itself felt through zoning regulations and building ordinances, in addition to outright ownership and operation of public parking.
From page 75...
... 18-75 ridesharing support, pedestrian-friendly design, and other means, preferably through multiple approaches. Parking management cannot reasonably be done in isolation.
From page 76...
... 18-76 commercial strip corridor between Bethesda and Rockville. While North Bethesda is an autodominated suburban environment, the Washington Metrorail system's Red Line has three stations within North Bethesda, including a station at White Flint.
From page 77...
... 18-77 time -- while the company also hoped to be growing -- a creative and lasting solution would be necessary to address the firm's commuting habits. Actions.
From page 78...
... 18-78 CBD Parking Supply Management in Portland, Oregon Situation. In 1972 carbon monoxide (CO)
From page 79...
... 18-79 technical studies, post-implementation trend analyses, planning documents, and personal interviews and communications. In addition, comparisons with parking characteristics in other cities, provided in various tables of the "Related Information and Impacts" section of this chapter under "Characteristics of Parking Demand" -- "Central Business District Parking," are commented upon.
From page 80...
... 18-80 Table 18-37 Portland CBD Trends in Daily Equivalent Monthly Parking Costs, in 1985 Constant Dollars a Survey Area 1983 1985 1987 1990 1991 1993 1995 1997 1999 CBD n/o W Burnside $2.12 b $2.01 b $2.02 $2.28 $2.30 $2.22 $2.26 $2.38 $2.86 CBD s/o W
From page 81...
... 18-81 Government. Personal Interviews with followup communications.
From page 82...
... 18-82 the 1992 completion of I-394, its HOV facilities, associated transit improvements, and the TAD garages. (The "Minneapolis I-394 HOV Facilities" case study in Chapter 2, "HOV Facilities," especially Table 2-25, should be referred to for detailed I-394 HOV usage and transit ridership information covering 1989, 1992, 1994, and 1996.)
From page 83...
... 18-83 Comsis Corporation, "Technical Memorandum: Characteristics of Effective TDM Programs. Final Report." Transit Cooperative Research Program Project B-4.
From page 84...
... 18-84 Iwata, S., and Lindmark, K., City of Portland Office of Transportation Planning. Personal Interviews with followup communications.
From page 85...
... 18-85 Scully, W J., "Parking Management in a Small Community: Back to basics." ITE Journal Vol.

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