HomeMy WebLinkAbout2022-02-02 ACHD Analysis TIS
Charlene Way
From:Sonya Allen
Sent:Wednesday, February 2, 2022 10:09 AM
To:Adrienne Weatherly; Charlene Way; Chris Johnson
Subject:Rackham East/Eagle View Landing Phase 2 - TIS Addendum for Silverstone Analysis
H-2021-0075
Please include in the public record. Thanks
From: Paige Bankhead <pbankhead@achdidaho.org>
Sent: Monday, January 31, 2022 10:02 AM
To: Christopher Bender <C.Bender@fehrandpeers.com>; Mindy Wallace <Mwallace@achdidaho.org>
Cc: Jon Wardle <jwardle@brightoncorp.com>; Tonn Petersen <tonn@bvadev.com>; Rob Sunderlage
<rob@bvadev.com>; john@brightoncorp.com; Preston Stinger <P.Stinger@fehrandpeers.com>; Sonya Allen
<sallen@meridiancity.org>
Subject: RE: Eagle View Landing Phase 2 - TIS Addendum for Silverstone Analysis
External Sender - Please use caution with links or attachments.
Good Morning,
The analysis and original study show that the intersection will operate exceeding LOS thresholds with and without the
additional traffic from Rackham East Subdivision. ACHD is supportive of restricting Rolling Hill Drive to emergency access
only with Rackham East Subdivision development since this intersection mainly serves the Rackham/ICCU development,
this development is part of the overall Rackham development area and the applicant understands the impacts of this
additional traffic. Currently, there is not enough existing right-of-way at Silverstone Way/Overland Road intersection for
additional improvements.
Please let me know if you have any questions.
Thank you,
Paige Bankhead, E.I.
Assistant Traffic Engineer
Ada County Highway District
Development Services
1301 N. Orchard St. Ste. 200
Phone: (208) 387-6293
We currently have a high volume of development applications and traffic impact studies that are under review and
review times are longer than usual. Thank you in advance for your patience.
1
From: Christopher Bender <C.Bender@fehrandpeers.com>
Sent: Friday, January 28, 2022 5:43 PM
To: Paige Bankhead <pbankhead@achdidaho.org>; Mindy Wallace <Mwallace@achdidaho.org>
Cc: Jon Wardle <jwardle@brightoncorp.com>; Tonn Petersen <tonn@bvadev.com>; Rob Sunderlage
<rob@bvadev.com>; john@brightoncorp.com; Preston Stinger <P.Stinger@fehrandpeers.com>
Subject: RE: Eagle View Landing Phase 2 - TIS Addendum for Silverstone Analysis
CAUTION: This email originated from outside your organization. Exercise caution when opening attachments or clicking
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Hi All,
This table shows the results of an analysis that assumes that Rolling Hill Drive’s project traffic is diverted to Silverstone
Way and that the eastbound approach match the description below. The dual eastbound left-turn lanes have been
restored to their existing single left turn lane configuration, and the signal timings have been reverted to the existing
protected+permitted phasing for that movement. The southbound direction now only includes one right turn lane but
still maintains the dual left-turn lanes as recommended previously, and as requested below; the signal phasing for this
movement has been converted to protected only, as dual left turn movements should avoid permitted phasing.
Table 7: 2023 Plus Project with Reduced Mitigations (No Rolling Hill Access) – Level of Service
Intersection Overall V/C AM Peak Hour PM Peak Hour
1
Lane Group
ID Location AM PM Movement V/C Movement V/C
EBL
1.15 1.44
EBTR
0.37 0.59
WBL
0.16 0.20
WBTR
0.84 1.19
NBL
Silverstone Way &
0.42 0.75
1 0.73 1.33
Overland Road
NBT
0.17 0.05
NBR
0.07 0.04
SBL
1.25 1.45
SBT
0.07 0.10
SBR
0.25 1.03
Interestingly, as shown in Table 7, the southbound right turn movement at Silverstone Way & Overland Road doesn’t fail
as badly as it did before, possibly due to the altered left turn phasing and the right-turn overlap for the southbound
right-turn; as the eastbound lefts went back to their old phasing, the right turn overlap gained extra protected green
time. However, a few other movements begin failing in this configuration, specifically the westbound through, and the
southbound left movements.
Thank you,
Christopher Bender, PE
Transportation Engineer
t: 385-282-7057 2180 South 1300 East | Ste 220
m: 702-556-7719 Salt Lake City, UT 84106
2
From: Paige Bankhead <pbankhead@achdidaho.org>
Sent: Thursday, January 27, 2022 10:50 AM
To: Christopher Bender <C.Bender@fehrandpeers.com>; Preston Stinger <P.Stinger@fehrandpeers.com>; Mindy
Wallace <Mwallace@achdidaho.org>
Cc: Jon Wardle <jwardle@brightoncorp.com>; Tonn Petersen <tonn@bvadev.com>; Rob Sunderlage
<rob@bvadev.com>; john@brightoncorp.com
Subject: RE: Eagle View Landing Phase 2 - TIS Addendum for Silverstone Analysis
Chris,
Thanks for the update. The assumption of the dual EB left turn lanes should also be removed since there isn’t enough
space to construct it per the staff report. There should only be dual SB left-turn lanes, 1 SB right-turn lane, and 1 EB and
WB left-turn lane.
We know that the intersection will operate worse with this traffic and it was already projected to exceed ACHD’s
acceptable v/c ratios with the original study, but we want an analysis that will reflect the actual configuration of the
intersection as it would be with the development and additional traffic.
Thanks,
Paige Bankhead, E.I.
Assistant Traffic Engineer
Ada County Highway District
Development Services
1301 N. Orchard St. Ste. 200
Phone: (208) 387-6293
We currently have a high volume of development applications and traffic impact studies that are under review and
review times are longer than usual. Thank you in advance for your patience.
From: Christopher Bender <C.Bender@fehrandpeers.com>
Sent: Thursday, January 27, 2022 12:57 AM
To: Paige Bankhead <pbankhead@achdidaho.org>; Preston Stinger <P.Stinger@fehrandpeers.com>; Mindy Wallace
<Mwallace@achdidaho.org>
Cc: Jon Wardle <jwardle@brightoncorp.com>; Tonn Petersen <tonn@bvadev.com>; Rob Sunderlage
<rob@bvadev.com>; john@brightoncorp.com
Subject: RE: Eagle View Landing Phase 2 - TIS Addendum for Silverstone Analysis
CAUTION: This email originated from outside your organization. Exercise caution when opening attachments or clicking
links, especially from unknown senders.
Hi Paige,
3
To keep this rolling as quickly as possible, here are the results of the analyses requested below. If these need to be
incorporated into the previous memo, let us know and we can include them in an updated draft.
Analyze a scenario that removes the assumption of dual right-turn lanes at Silverstone Way/Overland Road. We
are not requiring dual right-turn lanes with this development due to limited ROW.
This table shows the results of an analysis that assumes that Rolling Hill Drive’s project traffic is diverted to Silverstone
Way and that the eastbound approach at the intersection includes the dual left turns, as recommended in the August
st
2021. The only change from the analysis shown in Table 2 of the January 21 memo, is that the dual southbound right
turns at Silverstone Way & Overland Road were removed from this analysis.
Table 5: 2023 Plus Project with Reduced Mitigations (No Rolling Hill Access) – Level of Service
Intersection Overall V/C AM Peak Hour PM Peak Hour
1
Lane Group
ID Location AM PM Movement V/C Movement V/C
EBL
1.30 1.36
EBTR
0.41 0.60
WBL
0.13 0.18
WBTR
0.61 0.93
NBL
Silverstone Way &
0.31 0.74
1 0.73 1.33
Overland Road
NBT
0.12 0.05
NBR
0.05 0.03
SBL
0.41 0.88
SBT
0.05 0.10
SBR
0.47 1.55
As shown in Table 5, the southbound right turn movement at Silverstone Way & Overland Road significantly exceeds v/c
capacity without the dual southbound right turn.
Provide a table that shows the updated peak hour volumes for the Silverstone Way road segment with the
additional traffic and report the LOS. Acceptable LOS for a 5-lane collector is a peak hour directional volume of
1080, LOS D.
Table 6: 2023 Plus Project Roadway Segment Analysis
AM Peak PM Peak
Travel
Hour One-Hour One-AM PM
Functional Lanes
Roadway Segment Way Way Acceptable Acceptable
Classification (One-
Volume & Volume & LOS? LOS?
Direction)
LOS LOS
Rackham Way
Silverstone
to Overland Collector 2 983 / D 1197 / E YES NO
Way
Road
As shown in Table 6, the project volumes diverted from Rolling Hill Drive to Silverstone Way cause the PM peak hour
one-way segment volumes to exceed acceptable limits by 117 total trips. Since these project trips are driven by office
and residential land uses, it is likely that the project trips would be highest during peak commuting periods, that
shoulder hours would experience acceptable volumes, and that the unacceptable segment volumes would be limited to
the single PM peak hour.
Thank you,
4
Christopher Bender, PE
Transportation Engineer
t: 385-282-7057 2180 South 1300 East | Ste 220
m: 702-556-7719 Salt Lake City, UT 84106
From: Paige Bankhead <pbankhead@achdidaho.org>
Sent: Monday, January 24, 2022 11:27 AM
To: Preston Stinger <P.Stinger@fehrandpeers.com>; Mindy Wallace <Mwallace@achdidaho.org>
Cc: Jon Wardle <jwardle@brightoncorp.com>; Tonn Petersen <tonn@bvadev.com>; Rob Sunderlage
<rob@bvadev.com>; john@brightoncorp.com; Christopher Bender <C.Bender@fehrandpeers.com>
Subject: RE: Eagle View Landing Phase 2 - TIS Addendum for Silverstone Analysis
Good Morning,
I did a quick review of the update. I have a couple comments:
Analyze a scenario that removes the assumption of dual right-turn lanes at Silverstone Way/Overland Road. We
are not requiring dual right-turn lanes with this development due to limited ROW.
Provide a table that shows the updated peak hour volumes for the Silverstone Way road segment with the
additional traffic and report the LOS. Acceptable LOS for a 5-lane collector is a peak hour directional volume of
1080, LOS D.
Thanks!
Paige Bankhead, E.I.
Assistant Traffic Engineer
Ada County Highway District
Development Services
1301 N. Orchard St. Ste. 200
Phone: (208) 387-6293
We currently have a high volume of development applications and traffic impact studies that are under review and
review times are longer than usual. Thank you in advance for your patience.
From: Preston Stinger <P.Stinger@fehrandpeers.com>
Sent: Friday, January 21, 2022 5:23 PM
To: Paige Bankhead <pbankhead@achdidaho.org>; Mindy Wallace <Mwallace@achdidaho.org>
Cc: Jon Wardle <jwardle@brightoncorp.com>; Tonn Petersen <tonn@bvadev.com>; Rob Sunderlage
<rob@bvadev.com>; john@brightoncorp.com; Christopher Bender <C.Bender@fehrandpeers.com>
Subject: Eagle View Landing Phase 2 - TIS Addendum for Silverstone Analysis
5
CAUTION: This email originated from outside your organization. Exercise caution when opening attachments or clicking
links, especially from unknown senders.
Hello Paige and Mindy,
Happy Friday to you. The project team for Eagle View Landing Phase 2 wanted to explore the option of not having access
onto Rolling Hill Drive and instead shift that project traffic to Silverstone Way. The attached report is an addendum to
the original August 2021 TIS and provides the analysis results of this shift of traffic from Rolling Hill Drive to Silverstone
Way. Please review and let us know if you have any questions.
Thanks,
Preston
Preston Stinger, PTP, LEED GA
Fehr & Peers
T 385.282.7064 | M 801.755.2709
PTO Alert: I will be off-work from Jan 24-28.
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