Traffic Impact Study V1CHD
May 31, 2022
Lauren Nuxoll, PE, PTOE (Email)
Kittelson & Associates
Subject: Cobalt Point Apartments Traffic Impact Study - First Review
Mary May, President
Alexis Pickering, Vice -President
Jim D. Hansen, 21d Vice President
Kent Goldthorpe, Commissioner
Dave McKinney, Commissioner
The Ada County Highway District staff has completed the first review of the traffic impact study for
the proposed Cobalt Point Apartments. The traffic impact study was reviewed by JUB Engineers,
with comments reviewed and updated by Planning Review staff.
Table 1 shows no on -street parking on S Movado Way. Street parking is not prohibited on
Movado Way, please update the study.
2. Jade Way / Overland Road existing counts in Figure 3 and the Synchro reports don't
match the counts included in the appendix. The differences are minor and will not impact
the outcome of the analysis. Revisions are not necessary.
3. There may be an existing safety concern at the intersection of Eagle Road / Copper Point
Drive. There was a fatal angle crash reported at this intersection in addition to other
intersection related crashes. No other details or recommendations are included. Please
include details about the fatal crash and if additional safety measures need to be
implemented.
4. The study states that no improvements (CIP or IFYWP) are planned in the study area.
This is not accurate. The CIP includes widening Overland Road to seven lanes between
Eagle Road and Cloverdale Road between 2036 and 2040. Please update the study.
5. The study states that trips from in -progress development Movado Development were
added into the 2024 background volumes at the intersection of Movado Road / Overland
Road. The trips from this in -progress development were not included in the Appendix.
Please attach the Movado Development trip assignments to the study.
6. The tables in the TIS reports all lane groups with an LOS of F simply as having a delay
time > 50.0 seconds and all V/C ratios greater than 1.0 as V/C > 1.0 instead of reporting
the actual values from the Synchro reports. Please report the actual values.
7. The signal warrant analysis at the intersection of Eagle Road / Copper Point Drive
assumed one lane on the minor street approaches. Both minor approaches have two
lanes. The westbound approach is the higher volume approach. Based on the distribution
of traffic turning left and right at the intersection during the PM peak hour, two lanes should
be assumed for evaluating signal warrants. The signal warrant analysis also included all
right turning volume in the minor street approach volumes. The MUTCD states that
engineering judgement should be used to determine what, if any, portion of the right -turn
Ada County Highway District • 3775 Adams Street • Garden City, ID • 83714 • PH 208 387-6100 • FX 345-7650 • www.achdidaho.org
traffic is subtracted from the minor street traffic count when evaluating the count against
the signal warrants. It is recommended to subtract a portion of the right turning volume in
this scenario. Please update the study and analysis.
8. Cobalt Point Way & Copper Point Drive/Site Access A was evaluated with a V/C ratio of
0.96 in the AM Peak Hour for 2024 Total Conditions. A new approach is being added to
the intersection in Total Conditions and the intersection should be evaluated with a V/C
ratio of 0.90. Please update the study.
9. The TIS states that signal warrants are met for 2022 existing, 2024 background, and 2024
total conditions. The TIS should clearly state that ACHD's maximum V/C threshold is not
exceeded without mitigation in 2022 existing and 2024 background conditions and with the
addition of the northbound right turn lane in 2024 total conditions. Provide a discussion of
signal spacing and evaluation of the intersection as a signalized intersection and if it is
recommended.
9. Include turn lane warrant analysis for all two-way stop -controlled study intersections. Right
turn lane analysis should be completed for the intersections of Eagle Road / Copper Point
Drive, Jade Way / Overland Road, and Movado Way / Overland Road.
10. Provide the total number of peak hour trips that can be added to the intersection of
Movado Way/Overland Road before mitigation is warranted and the number of site trips
that can be added to the intersection of Eagle Road/Copper Point Drive before mitigation
is warranted.
11. The study needs to clarify if the proposed mitigation is feasible.
Please let me know if you have any questions.
Sincerely,
Paige Bankhead, PE
Traffic Engineer
Development Services
CC: City of Meridian — Bill Parsons
The Wolff Company — McKenzie Darr