Attachment D - PC Memo - Z-3-21-1

City of Phoenix — Formal (2021-06-02)

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To: 
City of Phoenix Planning Commission 
Date: May 4, 2021 
From: 
David Simmons 
Planner II – Village Planner 
Subject: ITEM NO. 9 (Z-3-21-1) – APPROXIMATELY 825 FEET SOUTH OF THE 
SOUTHWEST CORNER OF 23RD AVENUE AND PINNACLE PEAK ROAD 
This memo is to address an updated site plan and a request by the applicant regarding the 
recommended stipulation for a sound mitigation wall. 
The Deer Valley Village Planning Committee recommended approval of case Z-3-20-1 on 
March 8, 2021 per the staff recommendation by a vote of 10 to 1. After the Deer Valley 
Village Planning Committee meeting, the applicant submitted an updated site plan, date 
stamped April 19, 2021 (attached), reflecting updates to the side yard setbacks. The 
previous site plan reflected 10-foot side yard setbacks, which would have required 
variances. The updated site plan reflects 15-foot side yard setbacks, which complies with 
code requirements. 
In addition, the applicant has requested a modification to Stipulation No. 23 in regard to 
the sound mitigation wall. The request would allow the sound mitigation wall to wrap 
around the northwest and southwest corners of the site by 90 feet, rather than 120 feet. 
The applicant conducted a noise assessment (attached) that determined that the required 
decibel level could be achieved by the proposed 90-foot distance.  
Staff recommends the requested modification to Stipulation No. 23 to allow for the 
sound mitigation wall to wrap around the site by 90 feet, rather than 120 feet.  
Staff recommends approval, subject to the revised stipulations below: 
1.
The maximum building height shall be 30 feet.
2.
The development shall be limited to 297 units.
3.
The development shall be in general conformance with the elevations date
stamped March 24, 2021, as modified by the following stipulations and
approved by the Planning and Development Department.
4.
An enhanced landscaped entry shall be provided at the main entryway into the
development off of 23rd Avenue with a minimum 300 square feet of landscaped
area on each side of the entrance. The landscaped entries shall be planted and
maintained with a variety of at least three different plant materials, as approved
by the Planning and Development Department.
Attachment D

Z-3-21-1 Planning Commission Backup Memo  
May 4, 2021 
Page 2 of 4 
 
5. 
A minimum landscape setback of 25 feet shall be required along the west 
property line along the Interstate 17 (I-17) frontage road and shall include 
minimum 3-inch caliper large canopy shade trees planted a minimum of 20 feet 
on center or in equivalent groupings, as approved by the Planning and 
Development Department. 
 
 
6. 
There shall be a minimum of four private open space amenity areas, three of 
which shall be centrally located. A minimum of 6 percent of the area shall be 
preserved as open space exclusive of landscape setbacks. Each area shall 
provide, at a minimum, one of the following amenity elements or other similar 
elements, as approved by the Planning and Development Department:  
 
 
 
 Swimming Pool 
 
 
 
 Fire Pit 
 
 
 
 Pavilion or Ramada  
 
 
 
 Dog park  
 
 
7. 
The perimeter pedestrian pathway shall be provided as depicted on the site 
plan date stamped March 24, 2021 and shall reflect a common landscaping 
theme and include a minimum of three-inch caliper shade trees placed 20 feet 
on center exclusive of driveway/roadway crossings, as approved by the 
Planning and Development Department.   
 
 
8. 
Where pedestrian pathways cross drive aisles, the pathway shall be 
constructed of decorative pavers, stamped or colored concrete, or another 
material, other than those used to pave parking surfaces and drive aisles, as 
approved by the Planning and Development Department. 
 
 
9. 
Clearly defined, accessible pedestrian pathways shall be provided to connect 
building entrances, public sidewalks, and bus stops, using the most direct route 
for pedestrians, as approved by the Planning and Development Department. 
 
 
10. 
Perimeter walls shall incorporate stone veneer, stonework, integral color CMU 
block, split face block or faux stone, as approved by the Planning and 
Development Department. 
 
 
11. 
A minimum 5-foot-wide detached sidewalk shall be provided along 23rd 
Avenue with a minimum 13-foot-wide landscape area located between the 
sidewalk and back of curb and planted to the following standards, as approved 
by the Planning and Development Department. 
 
 
 
a. 
Minimum 3-inch caliper large canopy, single-trunk, shade trees placed a 
minimum of 25 feet on center or in equivalent groupings to provide a 
minimum of 75 percent shade on the adjacent sidewalk.

Z-3-21-1 Planning Commission Backup Memo  
May 4, 2021 
Page 3 of 4 
 
 
 
 
b. 
Drought tolerant shrubs and vegetative groundcovers with a maximum 
mature height of 24 inches to provide a minimum of 75% live coverage 
at maturity. 
 
 
12. 
Structural or vegetative shade shall be provided for every 8 parking spaces, as 
approved by the Planning and Development Department.  
 
 
13. 
The developer shall provide secured bicycle parking provide parking per 
Section 1307 of the City of Phoenix Zoning Ordinance. In addition, a minimum 
of eight inverted U-bicycle racks shall be provided for guests located near the 
club house/leasing office and installed per the requirements of Section 1307.H 
of the Zoning Ordinance, as approved by the Planning and Development 
Department. 
 
 
14. 
The developer shall dedicate minimum 50-feet of right-of-way and construct the 
west half of 23rd Avenue for the full limits of the project, per Cross Section D 
standards identified on the City of Phoenix Street Classification Map, as 
approved by the Planning and Development Department. 
 
 
15. 
In compliance with the Complete Streets Ordinance, the developer shall submit 
a signing and striping plan to include an extension of the bike lane for the full 
limits of the project frontage. 
 
 
16. 
A Red Border Letter shall be processed for this development, as approved by 
the Street Transportation Department.  
 
 
17. 
The developer shall construct all streets within and adjacent to the 
development with paving, curb, gutter, sidewalk, curb ramps, streetlights, 
median islands, landscaping and other incidentals, as per plans approved by 
the Planning and Development Department. All improvements shall comply 
with all ADA accessibility standards. 
 
 
18. 
The developer must file FAA Form 7460 and provide City FAA’s no hazard 
determination prior to construction permit approval, as per plans approved by 
the Planning and Development Department. 
 
 
19. 
The developer shall grant and record an avigation easement to the City of 
Phoenix Aviation Department for the site, per the content and form prescribed 
by the City Attorney prior to final site plan approval. 
 
 
20. 
The property owner shall record documents that disclose the existence, and 
operational characteristics of Phoenix Deer Valley Airport (DVT) to future 
owners or tenants of the property. The form and content of such documents 
shall be according to the templates and instructions provided which have been 
reviewed and approved by the City Attorney.

Z-3-21-1 Planning Commission Backup Memo  
May 4, 2021 
Page 4 of 4 
 
21. 
Prior to issuance of a final certificate of occupancy, the developer must install a 
sign (approximately 8 inches by 11 inches in size) within the development's 
sales/leasing office that is visible to prospective renters or purchases which 
discloses the proximity of the Deer Valley Airport and increased frequency of 
overflight and related aircraft noise, as approved by the Aviation Department. 
 
 
22. 
The indoor noise levels shall not exceed a decibel day night-level (DNL) of 45 
decibels and that along with the building plans submitted for Phoenix Building 
Construction Code compliance review to the Planning and Development 
Department there shall be a sealed and signed analysis by an engineer 
licensed in Arizona with a proficiency in residential sound mitigation or noise 
control. The engineer shall note in the analysis that the building design is 
capable of achieving the required Noise Level Reduction. 
 
 
23. 
Noise mitigation walls shall be provided along the western boundary of the 
development. The wall height shall be determined through a noise analysis 
prepared and sealed by a registered professional engineer. The walls shall 
contain no openings unless they are above the minimum height required for 
adequate noise mitigation or for drainage. The walls shall wrap around to the 
north and south property lines and shall continue for at least 120 90 feet, as 
approved by the Planning and Development Department. A wall detail sealed 
by a registered professional engineer, demonstrating that the walls will reduce 
noise to 65 Decibels or lower shall be submitted prior to preliminary site plan 
approval.  
 
 
24. 
If determined necessary by the Phoenix Archaeology Office, the applicant shall 
conduct Phase I data testing and submit an archaeological survey report of the 
development area for review and approval by the City Archaeologist prior to 
clearing and grubbing, landscape salvage, and/or grading approval.  
 
 
25. 
If Phase I data testing is required, and if, upon review of the results from the 
Phase I data testing, the City Archaeologist, in consultation with a qualified 
archaeologist, determines such data recovery excavations are necessary, the 
applicant shall conduct Phase II archaeological data recovery excavations. 
 
 
26. 
In the event archaeological materials are encountered during construction, the 
developer shall immediately cease all ground-disturbing activities within a 33- 
foot radius of the discovery, notify the City Archaeologist, and allow time for the 
Archaeology Office to properly assess the materials. 
 
Enclosures: 
Revised Site Plan date stamped April 20, 2021 
Noise Assessment (19 pages)

AZ Office 
CA Office 
 
4960 S. Gilbert Road, Ste 1-461 
1197 Los Angeles Avenue, Ste C-256 
 
Chandler, AZ 85249 
Simi Valley, CA 93065 
 
p. (602) 774-1950 
p. (805) 426-4477 
www.mdacoustics.com 
 
 
 
MD Acoustics, LLC 
1 
JN: 07942102_Letter Report4.15.21 
April 15, 2021 
 
Mr. Andrew Dutton
Mack Real Estate Development, LLC 
1150 S Olive Street, Ste 2250 
Los Angeles, CA 90015 
 
Subject: 
I17 & Pinnacle Peak Road Multi-Family Development  Noise Review Letter  
 Phoenix, AZ 
 
Dear Mr. Dutton:  
 
MD Acoustics, LLC (MD) is pleased to submit this letter as part of the noise assessment for the proposed 
I17 & Pinnacle Peak Road project located 22635 N Black Canyon Highway, Phoenix, AZ. The project 
proposes the construction of approximately 297 apartment units with 671 parking spaces, open space 
including outdoor pool on 19.6 acres. Exhibit A provides the location map and Exhibit B provides the 
project site plan.  A glossary of acoustical terms is located in Appendix A.  
 
1.0 
Local Acoustical Requirements 
The Black Canyon Freeway Specific Plan outlines the acoustical requirements and is as follows: 
703.A.2.a.(3) (Landscaping, Fences and Walls) 
Where a property line abuts or is adjacent to a freeway right-of-way, a noise mitigation wall exceeding the 
height limits in Section 703.A.2 may be erected under the following circumstances: 
a. The lot is in an area for which there is an approved Freeway Mitigation Specific Plan; and 
b. Wall height is indicated for that area in the Specific Plan or a noise analysis prepared by a 
registered professional engineer is submitted to the Planning and Development Department, which 
analysis demonstrates that the proposed wall height is required to reduce the noise level from 
freeway traffic to sixty-five dB(a) Ldn in outdoor living areas adjacent to the freeway. 
The Staff Report dated April 6, 20201 outlines additional acoustical requirements and is as follows: 
c. Noise mitigation walls shall be provided along the western boundary of the development. The wall 
height shall be determined through a noise analysis prepared and sealed by a registered 
professional engineer. The walls shall contain no openings unless they are above the minimum 
height required for adequate noise mitigation or for drainage. The walls shall wrap around to the 
north and south property lines and shall continue for at least 120 feet, as approved by the Planning 
and Development Department. A wall detail sealed by a registered professional engineer, 
demonstrating that the walls will reduce noise to 65 Decibels or lower shall be submitted prior to 
preliminary site plan approval.

I17 & Pinnacle Peak Road Multi-Family Development 
Noise Review Letter
Phoenix, AZ 
  
 
MD Acoustics, LLC
2
JN: 07942102_Letter Report4.15.21 
Exhibit A 
Location Map

I17 & Pinnacle Peak Road Multi-Family Development 
Noise Review Letter
Phoenix, AZ 
  
MD Acoustics, LLC
3
JN: 07942102_Letter Report4.15.21 
Exhibit B 
Site Plan

I17 & Pinnacle Peak Road Multi-Family Development 
Noise Review Letter 
Phoenix, AZ 
 
 
 
MD Acoustics, LLC 
4 
JN: 07942102_Letter Report4.15.21 
2.0 
Existing Noise Readings  
On 3/17/2021 to 3/19/20021, MD conducted a 48-hour noise survey at the site to evaluate the baseline 
noise conditions (I-17 & Pinnacle Peak Road Multi-Family Development  48-Hour Noise Survey  
Phoenix, AZ, dated 3/24/2021) . The data indicates the Ldn measured 67 dBA at the western property line 
and 60 dBA at the center of the site.  
 
3.0 
Evaluation Procedure 
3.1 
FHWA Traffic Noise Calculator 
ADOT 2019 traffic counts were input into the Federal Highway Administration Traffic Noise Calculator 
along with 2019 truck percentages and calibrated the model to the real-world measurements. These 
counts are in Appendix B. The model predicts a Ldn of 67 dBA at the west property line. 
 
3.2 
3D Model and Contour Map 
The noise level was modeled using SoundPLAN 3D (SP) acoustic modeling software. SP is capable of 
evaluating roadway 
based on FHWA traffic 
noise modelling software) to calculate the noise projections.  The software allows the user to input 
specific noise sources, spectral content, sound barriers, building placement, topography and noise 
sensitive receptors. The site is slightly elevated when compared to the centerline I17 Freeway elevation. 
The model uses ADOT 2019 traffic counts for SR-17 and vehicle mix data from ADOT. The model aligns 
with the Traffic Noise Model 2.5 and the baseline readings performed at the site. Appendix C provides the 
mo
 
 
4.0 
Findings 
4.1 
Exterior Traffic Noise Levels 
Four (4) receptors (R1 thru R4) were used to analyze the impact of noise from the freeway to the 
proposed project. R1 thru R4 evaluates 
C 
provides the baseline noise level contours at the project site with no sound walls. 
 
Exhibit D provides the abated sound levels at the project site which incorporates a 6-foot wall at the 
western property line and wraps around the north and south corners with a 90-foot length. With the 
incorporation on a 6-foot sound wall that wraps the corners (90-feet in length) the exterior level meets 
 the approximate location of the 
wall. 
 
Exhibit E provides the abated sound levels at the project site which incorporates a 6-foot wall along the 
backyards of the westerly dwelling units and wraps around the north and south corners with a 90-foot 
length. With the incorporation on a 6-foot sound wall that wraps the corners (90-feet in length) the 
approximate location of the wall. 
 
5.0 
Summary of Recommendations 
The following provides the recommendations for the project:

I17 & Pinnacle Peak Road Multi-Family Development 
Noise Review Letter 
Phoenix, AZ 
 
 
 
MD Acoustics, LLC 
JN: 07942102_Letter Report4.15.21 
 
1. A 6-foot tall or higher CMU privacy wall either placed at the western property line or at the 
backyards of the westerly dwelling units is required and must wrap the north and south corners of 
the site and extend east at least 90-feet in length. 
 
5.0 
Conclusions 
MD has evaluated the baseline noise condition for the I17 & Pinnacle Peak Road Multi-Family 
Development project located in Phoenix, AZ. The study shows that the unabated existing noise levels at 
the western property line is 67 dBA Ldn. With the incorporation of a 6-foot-tall CMU privacy wall, either at 
the western property line or at the backyard of the westerly dwelling units will reduced the exterior levels 
to approximately 60 
MD is pleased to provide this noise assessment.  If you have any questions regarding this analysis, call us 
at (602) 774-1950. 
 
Sincerely, 
MD Acoustics, LLC 
 
 
 
 
 
 
 
 
 
 
 
 
Mike Dickerson, INCE  
 
 
 
 
Principal

I17 & Pinnacle Peak Road Multi-Family Development 
Noise Review Letter
Phoenix, AZ 
  
 
MD Acoustics, LLC
6
JN: 07942102_Letter Report4.15.21 
Exhibit C 
Traffic Noise Level Impact to Project Site

I17 & Pinnacle Peak Road Multi-Family Development 
Noise Review Letter
Phoenix, AZ 
 
MD Acoustics, LLC
7
JN: 07942102_Letter Report4.15.21 
Exhibit D 
Traffic Noise Level Impact to Project Site

I17 & Pinnacle Peak Road Multi-Family Development 
Noise Review Letter
Phoenix, AZ 
 
MD Acoustics, LLC
8
JN: 07942102_Letter Report4.15.21 
Exhibit D 
Traffic Noise Level Impact to Project Site

Appendix A 
Glossary of Acoustical Terms

Glossary of Terms 
 
A-Weighted Sound Level: The sound pressure level in decibels as measured on a sound level meter using 
the A-weighted filter network.  The A-weighting filter de-emphasizes the very low and very high 
frequency components of the sound in a manner similar to the response of the human ear.  A numerical 
method of rating human judgment of loudness. 
 
Ambient or Background Noise Level: The composite of noise from all sources, near and far.  In this 
context, the ambient noise level constitutes the normal or existing level of environmental noise at a given 
location. 
 
Decibel (dB): A unit for measuring the amplitude of a sound, equal to 20 times the logarithm to the base 
10 of the ratio of the pressure of the sound measured to the reference pressure, which is 20 micro-
pascals. 
 
dB(A):  A-weighted sound level (see definition above). 
 
Equivalent Sound Level (LEQ): The sound level corresponding to a steady noise level over a given sample 
period with the same amount of acoustic energy as the actual time varying noise level.  The energy 
average noise level during the sample period. 
 
Field Sound Transmission Class (FSTC): The field sound transmission class (FSTC) rating is used for in situ 
wall and floor/ceiling sound isolation performance assessment. The standard requires the measurement 
of sound transmission loss and includes required procedure to show that the FSTC rating, as it has been 
determined by the test procedure, was not influenced by flanking of sound around the partition intended 
to be tested. Sound transmission class and FSTC ratings are intended by standard to be equivalent; 
however, practical experience indicates that FSTC ratings tend to be up to five ratings points less than 
laboratory-measured STC ratings. 
 
Day-Night Level (LDN or DNL): LDN is the average noise level over a 24-hour period. The noise between 
the hours of 10PM to 7AM is artificially increased by 10 dB. This noise is weighted to take into account 
the decrease in community background noise of 10 dB during this period.  
 
Noise: Any unwanted sound or sound which is undesirable because it interferes with speech and hearing, 
or is intense enough to damage hearing, or is otherwise annoying.  The State Noise Control Act defines 
noise as "...excessive undesirable sound...". 
 
Sound Level (Noise Level): The weighted sound pressure level obtained by use of a sound level meter 
having a standard frequency-filter for attenuating part of the sound spectrum. 
 
Sound Level Meter: An instrument, including a microphone, an amplifier, an output meter, and 
frequency weighting networks for the measurement and determination of noise and sound levels.

Appendix B 
Traffic Data

Appendix C 
SoundPLAN Input/Outputs