HomeMy WebLinkAboutWest Haven TIS, 2023-05-18, DRFT RPT AMND100 East Bower St., Suite 110
Meridian, ID 83642
(208) 288-1992
221237
Technical Memorandum
TO: Dennis Parker; Stone Castle Consulting
FROM: Stephen Lewis, PE, PTOE
DATE: May 18, 2023
SUBJECT: West Haven Development – Traffic Impact Study Amendment
The purpose of this memo is to amend the West Haven Development Traffic Impact Study (TIS), dated
April 25, 2022, and accepted by the City of Caldwell on May 25, 2022.
Since approval of the TIS last year, the developer has made changes to the type of residential housing
that will be included with the development. The portions that were not previously age restricted have
now been changed to age 55+ housing, as summarized below:
Original Land Use New Land Use
Single-Family Homes ....................... 75 units Townhomes (age 55+) .................... 221 units
Townhomes ...................................... 64 units 89 duplexes, 1 triplex, and 10 fourplexes
Apartments ....................................... 60 units Apartments (age 55+) ....................... 60 units
Single-Family Homes (age 55+) ..... 138 units Assisted Living ............................ 32,500 sq ft
Assisted Living ............................ 32,500 sq ft
Based on ITE Trip Generation rates, which are attached to this memo, the total number of forecast trips
will be reduced as follows:
· Average Daily Trips, reduced from 2,586 to 1,497 (42% reduction)
· AM Peak Hour Trips, reduced from 188 to 95 (49% reduction)
· PM Peak Hour Trips, reduced from 230 to 113 (51% reduction)
Attachments: Original and Revised Trip Generation Tables
Original Land Use:
New Land Use:
Veh Trips (T)
Total Enter Exit Total Enter Exit Total
210 Single-Family Detached Housing
Setting/Location: General Urban/Suburban Dwelling Units: 75 T = e0.92Ln(X) + 2.68 774 26% 74%T = e0.91Ln(X) + 0.12 15 42 57 63% 37%T = e0.94Ln(X) + 0.27 48 28 76
215 Single-Family Attached Housing
Setting/Location: General Urban/Suburban Dwelling Units: 64 T = 7.62(X) - 50.48 437 31% 69% T = 0.52(X) - 5.70 9 19 28 57% 43% T = 0.60(X) - 3.93 20 15 35
220 Multifamily Housing (Low-Rise)
Setting/Location: General Urban/Suburban Dwelling Units: 60 T = 6.41(X) + 75.31 460 24% 76% T = 0.31(X) + 22.85 10 32 42 63% 37% T = 0.43(X) + 20.55 29 17 46
251 Senior Adult Housing - Single-Family
Setting/Location: General Urban/Suburban Dwelling Units: 138 T = e0.85Ln(X) + 2.47 779 33% 67%T = e0.76Ln(X) + 0.16 16 33 49 61% 39%T = e0.78Ln(X) + 0.20 35 22 57
254 Assisted Living
Setting/Location: General Urban/Suburban 1,000 SF Gross Floor Area: 32.5 T = 4.19(X)136 75% 25% T = 0.38(X)9 3 12 32% 68% T = 0.48(X)5 11 16
Total 2,586 Total 59 129 188 Total 137 93 230
Enter% Exit%
Average Rate OR
Fitted Curve Equation
Veh Trips (T)
PM Peak Hour
of Adjacent Street, One Hour btwn 4 and 6pm
Average Rate OR
Fitted Curve Equation
Average Rate OR
Fitted Curve Equation
Veh Trips (T)
Enter% Exit%
ITE
Code Description Independent Variable (X)
Weekday AM Peak Hour
of Adjacent Street, One Hour btwn 7 and 9am
Veh Trips (T)
Total Enter Exit Total Enter Exit Total
251 Senior Adult Housing - Single-Family
Setting/Location: General Urban/Suburban Dwelling Units: 221 T = e0.85Ln(X) + 2.47 1,163 33% 67%T = e0.76Ln(X) + 0.16 23 48 71 61% 39%T = e0.78Ln(X) + 0.20 50 32 82
252 Senior Adult Housing - Multi-Family
Setting/Location: General Urban/Suburban Dwelling Units: 60 T = 2.89(X) + 24.82 198 34% 66% T = 0.19(X) + 0.90 4 8 12 56% 44% T = 0.25(X) + 0.07 8 7 15
254 Assisted Living
Setting/Location: General Urban/Suburban 1,000 SF Gross Floor Area: 32.5 T = 4.19(X)136 75% 25% T = 0.38(X)9 3 12 32% 68% T = 0.48(X)5 11 16
Total 1,497 Total 36 59 95 Total 63 50 113
PM Peak Hour
Average Rate OR
Fitted Curve Equation Enter% Exit%
Average Rate OR
Fitted Curve Equation
Veh Trips (T)
Enter% Exit%
Average Rate OR
Fitted Curve Equation
Veh Trips (T)ITE
Code Description Independent Variable (X)
Weekday AM Peak Hour