Trip Generation for Street and Highways

Lecture 14CE 4720

Norman Garrick

Trip Generation Calculations forStreet and Highway Construction

Norman W. Garrick

Storrs Center

Norman W. Garrick

Storrs Center Google Earth The Site

Norman W. Garrick

Storrs Center Google Earth The Site Constraints

Wetlands

Forest Reserve

Norman W. Garrick

Storrs Center Google Earth The Site Built Area

Norman W. Garrick

Storrs Center

Norman W. Garrick

Storrs Center Model

Norman W. Garrick

Storrs Center Model Village Road

Norman W. Garrick

Storrs Center Google Earth

Norman W. Garrick

Storrs Center 195 Problem

Norman W. Garrick

Storrs Center Importance of the Network

Norman W. Garrick

Using TG Manual without Correction

Proposed Trip Generation

Dwelling UnitsHouses 131 DU 9.60 1,258

Town Houses 42 DU 5.60 235Live Work DU 42 DU 3.60 151Apartments 140 DU 6.70 938

CommercialLive Work 21,000 SF 11.60 244

Mixed Use 1 181,800 SF 44.32 8,057Mixed Use 2 181,800 SF 42.90 7,799

LodgingHotel 350 Rooms 8.90 3,115Civic

Town Hall 42,000 SF 34.00 1,428Library 30,000 SF 44.00 1,320Pool 5,150 SF 16.00 82

Totals 24,628

Daily Trips

Land Use Size Trip Generation Classification Trip Gen Rates Trip Gen

Single-Family Detached Housing (210)Condominium/Townhouse (230)Condominium/Townhouse (230)

Apartment (220)

Single Tenant Office (715)Specialty Retail Center (814)

Shopping Center (820)

Library (590)Recreation Center (495)

Hotel (310)

Government Office (730)

Estimated number of trip ends = 24,600

ITE Trip Generation Manual

Proposed size of project

Norman W. Garrick

Using TG Manual with Correction for Mixed Use

Proposed Trip Generation

Dwelling UnitsHouses 131 DU 9.60 1,258

Town Houses 42 DU 5.60 235Live Work DU 42 DU 3.60 151Apartments 140 DU 6.70 938

CommercialLive Work 21,000 SF 11.60 244

Mixed Use 1 181,800 SF 44.32 8,057Mixed Use 2 181,800 SF 42.90 7,799

LodgingHotel 350 Rooms 8.90 3,115Civic

Town Hall 42,000 SF 34.00 1,428Library 30,000 SF 44.00 1,320Pool 5,150 SF 16.00 82

Mixed Use Internal Capture -4,926Pass-by Trips -3,786

Totals 15,916

20 % of Residential, Commercial, Lodging and Civic Trips25 % of External Commercial and Civic Trips

Library (590)

Daily Trips

Trip GenLand Use SizeTrip Gen

RatesTrip Generation Classification

Single-Family Detached Housing (210)

Condominium/Townhouse (230)

Hotel (310)

Single Tenant Office (715)Specialty Retail Center (814)

Apartment (220)

Condominium/Townhouse (230)

Government Office (730)

Shopping Center (820)

Recreation Center (495)

Estimated number of trip ends = 15,900It is very important to remember that this total includes walking, biking and transit trips

Not just car trips

360 State, New Haven Trip Generation

360 State, New Haven trip Generation over predict trips

The 360 State Street was estimated to produce 674 PM peak hour vehicle tripsRequiring the construction of 500 parking spaces

Live monitoring shows only 116 trips (17% of what was predicted)

- Mixed Use Trip Generation Model (New Haven and SCRCOG)

LOS, Volume CapacitySample Calculation

A two lane urban street has an ADT of 20,000 vehicles per day. Estimate what fraction of the year this street will operate at i) LOS E, ii) LOS D. Do this calculation for directional splits of 50% and 60%. The hourly volume distribution and the design hour service volumes are given on the following sheets.

Traffic Distribution

0 200 400 600 800 1000 1200 1400 1600 18000.05

0.06

0.07

0.08

0.09

0.1

0.11

Hour volumeas % of ADT

Number of Hours with traffic great thanshown

Design Hour Service Volume

Urban Streets with Frequent Signal Controlled Intersections

Source: http://www.dot.state.fl.us/planning/systems/sm/los/pdfs/lostables.pdf

Assumptions: > 4.5 Signalized intersection, 1.5 % heavy traffic, 12 % left turn, 12 % right turn

Level of Service Design Hour Service Volume

A

B

C 275

D 700

E 850

F >850

Ocean Springs – Biloxi Bridge

Biloxi – Gulfport Region

Ocean Springs – Biloxi Bridge Location

Ocean Springs – Biloxi BridgeADT Pre-Construction

2001 2002 2003 2004 20050

5000

10000

15000

20000

25000

30000

35000

Design Hour Service Volume

Source: AASHTO 1990

Level of Service Controlled Access Highway

Design Hour Service Volume per Lane

Uncontrolled Access Highway

Design Hour Service Volume per Lane

A 700 700

B 1100 1100

C 1550 1400

D 1850 1780

E 2000 2000

F >2000 >2000

LOS, Volume CapacityOcean Springs – Biloxi Bridge

Estimate the level of service for the Ocean Springs – Biloxi Bridge.