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From page 29... ... Smart growth requires smart calculations, thus impact fees need to account for the likely trip reduction effects of TOD. Study Projects This study aims to fill knowledge gaps by compiling and analyzing original empirical data on vehicle trip generation rates for a representative sample of multi-family housing projects near rail transit stations. Read the entire page →
From page 30... ... residential selfselection: for lifestyle reasons people consciously seek out housing near major transit stops for the very reason they want to regularly take transit to work and other destinations; studies in California suggest as much as 40% of the mode choice decision to commute via transit can be attributed to the selfselection phenomenon (Cervero, 2007) Read the entire page →
From page 31... ... . To further segment collected data, the team used a national database from the CTOD to compile basic demographic data for the neighborhoods of each of the rail stations serving the selected TODs, including information on residential densities, car ownership, and median income. Read the entire page →
From page 32... ... First, simple descriptive statistics were prepared on vehicle trip generation rates, defined in such standard terms as: average weekday vehicle trips per dwelling unit and one-hour AM and PM vehicle trips per dwelling unit. [ITE define average weekday trip rate as the weekday (Monday through Friday) Read the entire page →
From page 33... ... 33 Avalon at Grosvenor Station Lenox Park Apartments Gallery at Virginia Square Quincy Plaza Meridian at Braddock Park Figure 2.3. Locations of study sites in metropolitan Washington, D.C.: Avalon; Gallery at Virginia Square; Meridian; Quincy Plaza; Lenox Park. Read the entire page →
From page 34... ... 34 Quatama Crossing Apartments Collins Circle Apartments The Merrick Apartments Center Commons Gresham Central Apartments Figure 2.4. Locations of study sites in metropolitan Portland, Oregon: Center Commons; Collins Circle; Gresham Central; The Merrick; Quatama Crossing. Read the entire page →
From page 35... ... 35 Montelena Apartments Mission Wells Apartments Wayside Commons Park Regency Verandas Apartments Figure 2.5. Locations of study sites in San Francisco-Oakland Metropolitan Area: Mission Wells, Montelena, Park Regency, Verandas, Wayside Commons. Read the entire page →
From page 36... ... metropolitan area. Among the five mid-tohigh rise apartment projects near Metrorail stations outside the District of Columbia, vehicle trip generation rates were more than 60% below that predicted by the ITE manual. Read the entire page →
From page 37... ... + 150.35, where T = average vehicle trip ends and X = number of dwelling units. Fitted Curve Equation for Condominiums (Wayside Commons) Read the entire page →
From page 38... ... The ITE manual, however, presents weighted averages of trip generation by summing all trip ends among cases and dividing by the sum of dwelling units. Thus for apple to apple comparisons, weighted average vehicle trip rates were computed for all 38 Read the entire page →
From page 39... ... + 4.21 where T = average vehicle trip ends and X = number of dwelling units. Fitted Curve Equation for Condominium (Wayside Commons) Read the entire page →
From page 40... ... + 17.52 where T = average vehicle trip ends and X = number of dwelling units Fitted Curve Equation for Condominium (Wayside Commons) Read the entire page →
From page 41... ... Comparison of weighted average vehicle trip rates: TOD housing and ITE estimates. 5000 4000 3000 2000 1000 0 0 200 400 600 X = Number of Dwelling Units T = W ee kd ay T rip E nd s 800 1000 T=-523.7+5.262X R2=0.729 Figure 2.7. Read the entire page →
From page 42... ... This is supported by the results shown in Table 2.6. The predictor variable in all of these equations is residential density, specifically the number of dwelling units per gross acre within a half mile radius of the rail station closest to the TOD housing project, estimated from the 2000 census. Read the entire page →
From page 43... ... TOD Rate as a Proportion of ITE Rate 0.801 - .096X 0.424 Vehicle Trip Ends per Dwelling Unit 0.400 - .014X 0.276 AM Peak Hour TOD Rate as a Proportion of ITE Rate 0.731 - .026X 0.274 Vehicle Trip Ends per Dwelling Unit 0.493 - .019X 0.449 PM Peak Hour TOD Rate as a Proportion of ITE Rate 0.741 + .028X 0.423 Table 2.6. Summary regression equations for predicting TOD housing trip generation rates as functions of residential densities (within 1/2 mile of stations) Read the entire page →
From page 44... ... Summary regression equations for predicting TOD housing trip generation rates as functions of walking distance to nearest station. Read the entire page →
From page 45... ... Weekday TOD Trip Generation Model The simple bivariate models shown in Table 2.6 provided the best fit for predicting weekday TOD trip generation rates (as well as rates as a proportion of the ITE rate) Read the entire page →
From page 46... ... Model 4: TOD Trip Generation Model for PM Peak (as a Proportion of ITE Rate) The best-fitting multiple regression equation was produced for predicting PM peak trip rates as a proportion of ITE rates (Table 2.12) Read the entire page →
From page 47... ... Best-fitting multiple regression equation for predicting PM peak trip generation rates as a proportion of ITE rate for TOD housing projects. Distance to CBD (miles) Read the entire page →
From page 48... ... Reducing parking from 2.2 to 1.1 spaces per unit resulted in the ability to increase the potential number of units on the site by 33% for both garden apartments and townhomes. The greatest absolute increase in the number of units was achieved by Total Area: 8 acres 2.2 Parking spaces per unit 1.1 Parking spaces per unit Total Area: 8 acres Total Units: 256 Total Units: 196 Additional units: 60 Density: 32 Dwelling units per acre Density: 24 Dwelling units per acre Increase in density: 33% Parking Spaces: 432 Parking Spaces: 288 Parking capital cost: $2.02m Parking capital cost: $2.1m Parking cost savings: $98,000 Annual incremental ridership: +19,500 Annual incremental fare revenue: $19,750 Figure 2.19. Read the entire page →
From page 49... ... As the case study shows, a reduction in parking results in an increase in the number of potential units on the site (which need to be parked) by 20% to 33% Total Area: 8 acres Total Area: 8 acres Total Units: 384 Total Units: 288 Additional units: 96 Density: 48 Dwelling units per acre Density: 36 Dwelling units per acre Increase in density: 33% Parking Spaces: 648 Parking Spaces: 448 Parking capital cost: $5.82m Parking capital cost: $6.56m Parking cost savings: $736,000 Annual incremental ridership: +31,200 Annual incremental fare revenue: $31,600 2.2 Parking spaces per unit 1.1 Parking spaces per unit Figure 2.20. Read the entire page →
From page 50... ... Transit ridership: 3.55 trips per TOD household allocated as follows: 1.5 work trips per TOD HH ∗ TOD units ∗ .40 TOD work mode share + 4 nonwork trips per TOD HH ∗ TOD units ∗ .10 TOD nonwork mode share (Lund et al., 2004) = daily ridership × 325 annualization factor = the annual incremental increase in ridership attributable to changes in parking ratios. Read the entire page →
From page 51... ... Based on this evidence, public officials and government regulators may chose to develop new, more realistic standards for parking, assessing impact fees, and mitigation for TODs. The research suggests important implications are Total Area: 8 acres Total Area: 8 acres Total Units: 963 Total Units: 738 Additional units: 225 Density: 120 Dwelling units per acre Density: 92 Dwelling units per acre Increase in density: 20% Parking Spaces: 1152 Parking Spaces: 864 Parking capital cost: $15.98m Parking capital cost: $21.31m Parking cost savings: $5.3m Annual incremental ridership: +82,875 Annual incremental fare revenue: $83,950 2.2 Parking spaces per unit 1.1 Parking spaces per unit Figure 2.22. Read the entire page →
From page 52... ... . It must be noted that the ability to increase density Units Density Parking Total Additional Per acre % increase Spaces Cost Difference Annual Incremental Ridership Garden Apartments TOD 1 ratio 256 +60 units 32 +33% 288 $2.02m TOD 2 ratio 196 24 432 $2.1m $98,000 savings 19,500 transit trips $19,750 fares Townhomes TOD 1 ratio 384 +96 units 48 + 33% 448 $5.82m TOD 2 ratio 288 36 648 $6.56m $736,000 savings 31,200 transit trips $31,600 fares Mid Rise 6-Story TOD 1 ratio 963 +162 units 120 +20% 1152 $21.31M TOD 2 ratio 801 100 1800 $33.3m $12 million savings 52,650 transit trips $53,330 fares Texas Donut TOD 1 ratio 963 +225 units 120 +30% 1152 $21.31m TOD 2 ratio 738 92 864 $15.98m $5.3 million savings 82,875 transit trips $83,950 fares Assumptions: Parking ratios: TOD 1 - 1.1 spaces per unit; TOD 2 - 2.2 spaces per unit Cost per space: surface parking $7,000; tuck under parking $14,000; structured parking $18,500 Transit ridership: 3.55 trips per TOD household allocated as follows: 1.5 work trips per TOD HH * Read the entire page →
From page 53... ... Local officials and neighborhoods may be more apt to support increases in residential densities near transit if they are shown proof that up to half of the trips result from TODs than in conventional development. Using a 700-unit California condominium project as a reference point, the expected daily traffic rates would be reduced by as much as half with a likely number of 2,350 trips with the TOD traffic generation rates rather than 4700 daily trips using the ITE rates (S. Read the entire page →
From page 54... ... This can mean TOD developers end up paying higher impact fees, proffers, and exactions than they should since such charges usually are tied to ITE rates. Another implication of the research is that parking ratios for residential TODs also are likely to be overstated for TODs by the same order of magnitude since they also are based on ITE data. Read the entire page →
From page 55... ... Recommendations With this research data to support the belief that people living in TODs drive less often than their neighbors in conventional developments, public officials and government regulators have the evidence needed to develop new, more realistic standards for assessing impact fees and mitigation for TODs. Developing residential TODs based on an accurate assessment of their traffic impacts should result in easier development approvals, better planned and more compact communities, increased transit ridership, and more affordable housing. Read the entire page →
From page 56... ... A mode share survey could be mailed to residents of selected TODs and analyzed at a cost of approximately $3,500 per TOD. The before and after study of Center Commons referenced in the literature review was done in this manner. Read the entire page →

From page 29...

... Smart growth requires smart calculations, thus impact fees need to account for the likely trip reduction effects of TOD. Study Projects This study aims to fill knowledge gaps by compiling and analyzing original empirical data on vehicle trip generation rates for a representative sample of multi-family housing projects near rail transit stations.