1 AUARI t
CITYOF
CHANHASSEN
7700 Market Boulevard
PO Box 147
Cha~hasserl MN 55317
,~,dministration
Phone: 9522271100
Fax; 952 227 1110
Phone: 952 227 1180
Fax; 952227 1!90
Engineering
Phone: 9522271160
Fax: 952 2271170
Finance
Park & Recreation
Fax 952 227 1110
Recreation Genter
2310 Oou'4er Bouiavar{l
Pt~one: 952 2271400
Fax: 952 2271404
Planning &
Natural Resources
Pl~one: 9522271130
Fax 9522271110
Public Works
1591 Parx Road
Phone: 952227 1300
Fax 952227 1310
Senior Center
P~or e 952227 1!25
Fax: 95222? 1110
Web Site
ww,~, ci chan~]asser' mn us
MEMORANDUM
To: Planning Commission
From: Kate Aanenson, AICP, Community development Director
Date: August 27, 2002
Subj: AUAR
Background
The AUAR appeared as a public hearing before the Planning Commission on
August 19th. This item was continued until September 2nd when the Traffic Noise
and Air Quality will be presented.
Analysis
Attached is the Traffic and Noise Study for the AUAR. Consultants on the project
will be at the meeting to review the material and answer questions. A complete
draft of the changes to the AUAR and a working draft of the mitigation plan will
also be provided at the meeting as well as reviewed with the commission.
Recommendation
After the public hearing has been opened and closed for comment. Staff is
recommending the AUAR be published in the September 15, 2003 Environmental
Quality Board Monitor. The next step will be the adoption of the AUAR with
the proposed mitigation at the November l0th or 24th City Council meeting.
The City of Chanhassen · A growing cor-]munity wilh clear] lakes quality schools a chamfing dow~llovv'!1 thrivir'g businesses winding trails, and beaulitul parks A gr,;at i}i~ce t: i~,r ,t,,cr~< snd !;,i,,~
I-DR
ONE COMPANY [Many Solutions,.
August26,2003
Mr. Gary Ehret, PE
Kimley-Horn and Associates, Inc.
2550 University Avenue West Suite 345N
St. Paul, MN 55114-2006
Re: Traffic Noise and Air Quality Study for Chanhassen, MN AUAR
Dear Gary:
Thank you for the opportunity to perform a traffic noise and air quality analyses for the
Chanhassen AUAR project. The following text presents results of our analyses.
NOISE ANALYSIS
Introduction
HDR Engineering, Inc. (HDR) measured existing noise levels at three locations in the project
area. Monitoring locations represented undeveloped land that is likely to be developed for
residential use. HDR modeled the future Build alternative and traffic volumes for the year
2025, using the Minnesota Department of Transportation traffic noise model, MINNOISE.
Monitoring data and modeling results were compared with the Minnesota Pollution Control
Agency (MPCA) Noise Rules, and traffic noise impacts were evaluated. Modeling results
were used to create noise contours showing the location of the residential daytime and
nighttime L10 and L50 noise contour lines. Project location maps are included as Figures 1
and 2 at the end of this report.
Existing Noise Levels
On August 20 and 22, 2003, HDR performed noise monitoring at three locations in the project
area. The purpose of the noise monitoring was to document existing noise levels. Noise
measurements were conducted in accordance with Minnesota Rules Chapter 7030, Noise
Pollution Control.
The average meteorological conditions were reported as shown in Table I below.
Table 1
Meteorological Conditions for August 20 & 22, 2003
Temperature 8/20/03 - 94°, 8/22/03 - 61 °
Humidity 8/20/03 _-- 47%, 8/22/03 _-__ 93%
Wind 8/20/03 breezy; 8/22/03 N/A
Conditions Partly Cloudy
8/20/03 - 29.71 inches;
Barometric Pressure
8/22/03 - 30.12 inches
Chanhassen A UAR Noise and Air Quality Analysis
August 26, 2003
Page 2 of 8
The microphones were covered with a windscreen and when placed on a tripod, were set to a
height of approximately 5 feet for all measurements. The Sound Level Meters (SLM) were
calibrated before and after the monitoring activities. No significant calibration drifts were
detected during the monitoring events. Table 2 summarizes the equipment HDR staff used to
collect monitoring data for this noise analysis.
Table 2
Noise Analysis Instrumentation Summary
Instrument Make Model
Sound Level Meter Quest 2900 Sound Level Meter
Technologies with Octave Band Filter
Calibrator Quest
Technologies QC-10/QC-20
Sound Level Meter Larson Davis 712
Calibrator Larson Davis CALl50
Calibration
Due
June 20,2004
June 20,2004
November22,2003
November22,2003
Serial Number
HV7120016
QE7120219
0315
0421
The monitoring sites were selected at locations to get a representation of the no~se emissions
from the existing roadways (Audubon Road, Lyman Boulevard). Site 1 was located
approximately 81 feet from the Audubon Road centerline, close to where the intersection with
the East-West collector will be. Site 2 was located approximately 62 feet from the Lyman
Boulevard centerline, near the intersection with Audubon Road. Site 3 was located
approximately 81 feet from Lyman Boulevard, near where the North Collector will intersect
Lyman Boulevard.
The results are listed in Tables 3 (daytime) and 4 (nighttime) below and the locations are
indicated on Figures I and 2. Daytime means those hours from 7:00 a.m. to 10:00 p.m.
Nighttime means those hours from 10:00 p.m. to 7:00 a.m. MI>CA maximum allowable
daytime noise levels are 65 dBA (L10) and 60 dBA (L50), and nighttime noise levels are 55
dBA (L10) and 50 dBA (L50).
Site
1
2
3
Table 3
Daytime Noise Monitoring Summary
Distance MPCA Daytime Exceedance
Date Time L10 LS0
From L10 L50 (Yes/No)
Sampled Sampled CL (dBA) (dBA) (dBA) (dBA)
August 20, 2003 4:00-5:00 p.m. = 8l' 67 62 65 60 Yes
August 20, 2003 4:08-5:08 p.m. = 62' 66 60 65 60 Yes
August 20, 2003 5:05-6:05 p.m. = 81' 73 64 65 60 Yes
Chanhassen A UA R Noise and Air Quali~.' Analysis
August 26, 2003
Page 3 of 8
Table 4
Nighttime Noise Monitoring Summary
Distance MPCA Nighttime Exceedance
Date Time L10 L50
Site From L10 L50 (Yes/No)
Sampled Sampled CL (dBA) (dBA) (dBA) (dBA)
1 August 22, 2003 4:57-5:57 a.m. = 81' 73 64 55 50 Yes
2 August 22, 2003 5:57-6:57 a.m. -- 62' 69 62 55 50 Yes
3 August 22, 2003 6:00-7:00 a.m. = 81' 65 59 55 50 Yes
None of the sites monitored are developed. Both daytime and nighttime noise levels exceed
MPCA Standards. Monitoring was done during morning and evening rush hour with heavy
traffic traveling at approximately 50 mph and at locations within 81 feet of the roadway
centerline.
Future Noise Levels
The modeling analysis utilized proposed roadway design details and traffic information
supplied by Kimley-Horn and Associates, Inc. HDR loaded a digital plan view of the
proposed roadway into Arcview, a geographic information system (GIS) program and
digitized roadway coordinates for use in the MINNOISE input file. Audubon Road, Lyman
Boulevard, North Collector, South Collector, and East-West Collector were digitized and
modeled for the Build Alternative.
The analysis modeled peak hour projected traffic volumes for the year 2025. The peak hourly
traffic volumes (PHV) of the various locations are shown in Table 5.
Roadway speeds were modeled as follows:
· Audubon Road - 50 mph
· Lyman Boulevard - 50 mph
· North Collector - 40 mph
· South Collector - 40 mph
East-West Collector - 45 mph
Chanhassen A UAR Noise and Air Quality Analysis
August 26, 2003
Page 4 of 8
Location
Table 5
Peak Hourly Traffic Volumes (Build Condition)
Design (2025)
Daytime PHV
Audubon Road
Pioneer Trail to Butternut Dr.
Butternut Dr. to Lakeview
Lakeview to Lyman
Lyman Boulevard
Audubon to Audubon N.
Audubon N. to N. Collector
N. Collector to Powers
East-West Collector
Audubon to S. Collector
S. Collector to N. Collector
N. Collector to Powers
North Collector
South Collector
Pioneer Trail
Audubon to S. Collector
S. Collector to Bluff Creek
Bluff Creek to Powers
Design (2025)
Nighttime PHV
1094 300
1105 309
1005 281
1595 447
1449 406
1544 432
934 262
815 228
1138 319
160
239
45
67
1264 354
1561 437
1186 332
Table 6 shows the vehicle mix provided by Kimley-Hom and Associates, Inc. that was used in
this traffic noise analysis.
Table 6
Vehicle mix used for Chanhassen AUAR
Autos MT HT
98% 0 2%
Results
Modeling results are shown as contours on Figures 1 and 2. Traffic noise levels between the
roadway and contour line are predicted to exceed the corresponding Residential
Daytime/Nighttime LI0/L50 noise levels. Table 7 shows these distances in tabular form.
Chanhassen A UAR Noise and Air Quality Analysis
August 26, 2003
Page 5 of 8
Table 7
Distance to Contours - Build Condition (2025)
Approximate Distance from CL in Feet
Location
Audubon Road
Pioneer Trail to
Butternut Dr.
Butternut Dr. to
Lakeview
Lakeview to
Lyman
Lyman Boulevard
Audubon to
Audubon N.
Audubon N. to
N. Collector
N. Collector to
Powers
East-West Collector
Audubon to S.
Collector
S. Collector to
N. Collector
N. Collector to
Powers
North Collector
South Collector
MPCA Daytime
L10 L50
(dBA) (dBA)
134 119
176 121
164 91
MPCA Nighttime
L10 L50
(dBA) (dBA)
136 187
142 205
115 180
171 150 157 245
161 150 151 247
165 175 172 275
75 75 75 75
125 82 95 100
145 96 125 150
40 40
65 35
I 40 40
I 40 40
Residences located within the distances above (from the roadway centerline) are predicted to
experience roadway noise levels that may exceed the MPCA's maximum allowable noise
levels.
Predicted future noise levels at the monitoring locations are shown in Tables 8 and 9 below.
Chanhasset~ A UAR Noise and Air Quali(v Ana(vsis
August 26, 2003
Page 6 of 8
Table 8
Daytime Noise Modeling Results at Monitoring Locations
L10 L50 MPCA Daytime Exceedance
Site (dBA) (dBA) Limits (Yes/No)
L10 L50
(dBA) (dBA)
I 69 62 65 60 Yes
2 72 65 65 60 Yes
3 70 63 65 60 Yes
Table 9
Nighttime Noise Modeling Results at Monitoring Locations
L10 L50 MPCA Nightime Exceedance
Site (dBA) (dBA) Limits (Yes/No)
L10 L50
(dBA) (dBA)
1 64 54 55 50 Yes
2 66 57 55 50 Yes
3 64 55 55 50 Yes
Both daytime and nighttime future (2025) build modeling results indicate that future traffic
noise levels may exceed MPCA maximum allowable noise levels at the monitoring locations.
This is reasonable because these locations lie within the noise contour lines shown in Figures
1 and2.
The proposed Highway 212/312 alignment and its ramps were modeled for a previous
environmental review document. The proposed highway and its ramps are not a feature of
this project and are therefore not included in this analysis. Interested readers should obtain
and review the environmental document prepared in support of the proposed highway for
information about predicted noise levels associated with those roadways.
Mitigation
Results of these analyses suggest that future traffic noise levels may exceed MPCA's
maximum allowable noise levels near roadways in the project area. The City of Chanhassen
is required to comply with MN Rules section 7030.0030. This section requires the City to
ensure that existing noise levels comply with state noise limits prior to occupants moving into
residences in the proposed development. Traffic noise levels may be reduced by a
combination of earthen berms and aesthetically designed noise walls that fit the theme of the
proposed development. More detailed noise analyses should be performed for each specific
development proposed for the project area.
AIR QUALITY
Existing Conditions
Most of the Chanhassen area, located in northeastern Carver County, is only lightly developed
with industrial, commercial, or residential developments. Monitored concentrations for
pollutants subject to National Ambient Air Quality Standards (NAAQS - see 40 CFR 50) are
Chanhassen A UAR Noise and Air Quali(v Aualysis
August 26, 2003
Page 7 of 8
not available based on a check of the US Environmental Protection Agency's (EPA's) online
AIRS database. These pollutants include carbon monoxide (CO), lead (Pb), nitrogen oxides
(NO×), ozone (03), particulate matter under 10 microns in diameter (PM~0), particles under 2.5
microns in diameter (PM2.5), and sulfur dioxide (SO2).
For developments involving new or expanded roadways, the pollutants of primary concern for
project-level impacts are CO and PM~0 (see Transportation Conformity rules under 40 CFR
91, Subpart A). These pollutant emissions are due to motor vehicle exhaust and fugitive dust
resuspension by moving vehicles. While monitoring data for these pollutants are not
available in Carver County, such data are being monitored in more densely populated and
highly developed areas of Hennepin County, which is just northeast of Carver County. The
Hennepin County CO and PM~0 data available on the EPA's AIRS web site indicate that
monitored concentrations are well below the limits established by NAAQS.
Project Impacts
The EPA and MPCA currently do not require PM~0 analysis and dispersion modeling for
roadway projects. However, such projects can sometimes require a CO hot-spot analysis
under current rules. The Minnesota Department of Transportation (MnDOT) has developed a
screening process to determine when potentially adverse CO impacts might occur, and which
must then be analyzed using hot-spot analysis procedures. These procedures are based on the
total average daily traffic (ADT) volumes for intersections affected by the project.
According to MPCA procedures, a subject project requires a CO hot-spot analysis if the
project will: 1) affect traffic at one of three monitored (for CO) intersections, 2) affect traffic
at one of seven MnDOT-listed intersections with high traffic levels, or 3) would have traffic
levels in excess of a benchmark level of 77,200 vehicles per day.
Based on year 2025 traffic forecasts for intersections in the project area, the highest total daily
traffic volume for any intersection in the immediate project area will occur at Powers Road
and Lyman Boulevard, with 29,227 vehicles per day. This is far below the MnDOT
benchmark level to require modeling.
Regarding items 1 & 2 above, the nearest of the ten (I0) specified intersections to the project
area is the intersection of TH-7 and TH-101, located approximately 6 miles north-northeast of
the project area. Based on the current and planned (by 2025) highway network for the area,
the primary routes of access would be from the future Highway 212/312 routes, which will
provide access to the project area from the greater metropolitan area. No project-related
impact is expected on the TH-7/TH-101 intersection. Therefore, this development would not
fall under MnDOT analysis guidelines, and is presumed to have minimal impact on air
quality.
Finally, CO emissions from motor vehicles, as well as ambient CO concentration levels, are
continuing to fall, as the nation's motor vehicle fleet is modernized with lower-emitting
vehicles. Despite population growth in most metropolitan areas of the country, the reduction
in per-vehicle CO emissions has more than offset the increased number of vehicles traveling
the highways.
Chanhassen A UAR Noise ami Air Quality Analysis
August 26, 2003
Page 8 of 8
Thanks for the opportunity to provide HDR's environmental acoustics services. I can be
reached at (763) 591-5450 if you have questions or comments about this analysis. We're an
employee-owned company, thanks for choosing HDR.
Sincerely,
HDR Engineering, Inc.
Timothy G. Casey, QEP
Environmental Acoustics Program Manager
Attachments: Figures 1 through 2
700 0
700
1400 Feet
Chanhassen AUAR
Daytime Noise Contours
,,;
,,,
//'
,
//
,,',,
Figure 1
700 0
II
I
II
700
1400 Feet
Chanhassen AUAR
Nighttime Noise Contours
Figure 2
MEMORANDUM
Hoisington Koegler Group Inc.
gin
To:
From:
Subject:
Date:
Kate Aanenson
Loren Gordon and Brad Scheib
Updates to the 8/13/2003 AUAR Draft
August 27, 2003
This updated memorandum is an inclusive inventory of updates to the August 13, 2003 Draft AUAR that
appear in the August 27~h, 2003 Draft. Updated information in this memo includes those sections of the
report with substantive changes. Sections where revisions were made to correct minor spelling,
grammatical, and clarifying text are not included in this memo.
The following is a summary of revisions noted in the August 27th, 2003 Draft.
EXECUTIVE SUMMARY
Replace the following sections on Page 6 of the August 13th Draft:
Land Use
A hypothetical development scenario was generated for the project area. This scenario is based on the
directions established within the 2020 Comprehensive Plan approved in June of 1999 with the exception of
a school facility located on the northwest portion of the site. The school facility is shown as an alternative
land use for the Office/Industrial designation for the site (referred to as the Degler property). A school
facility would be a middle or high school with enrollment of roughly 1,700 students. Besides the physical
class room facility, recreation fields would be necessary. The Comprehensive Plan would permit land uses
such as medium density residential, office, industrial and park and open space. Under the development
scenario assumed for this project, development projections include roughly 1,500 new housing units
(consisting of a mix of small lot single family, townhome and condominium type housing) and roughly
700,000 square feet of new light industrial/office space. These projections assume maximum densities and
lot coverages based on existing comprehensive plan policies and zoning ordinance provisions.
Municipal Infrastructure
Municipal sewer and water facilities have been planned to serve this area consistent with the projections of
the development scenario. Sanitary sewer service would be served through Lift Station #24 located at
Lyman Boulevard and Audubon Road except for the portion of the project area lying east of TH 212/312.
This area will require a new lift station and force main which will serve the next MUSA expansion area
starting in 2010. No future wells are anticipated in the project area as a result of the development scenario.
A distribution system would be built to serve new development with water supply from the Central Water
Treatment Plant (site 10).
Storm sewer improvements would be built in conjunction with other infrastructure systems. The City's
Storm Water Management Plan was adopted in 1994 and needs to be upgrade. The current plan illustrates a
system of wetlands, ponds and pipes that when linked together provide sufficient capacity to serve the
project area. The use of wetlands has been further regulated by changes to the Wetland Conservation Act
and needs to be updated in the SWMP. New National Pollutant Discharge Elimination System (NPDES)
Phase II requirements recently promulgated also regulate individual site development requirements.
123 North Third Street, Suite 100, Minneapolis, MN 55401-1659
Ph (612) 338-0800 Fx (612) 338-6838 www~hkgi.com
Kate Aanenson
August 27, 2003
Page 2
6. DESCRIPTION
Replace the Development Scenario section on Page 12 of the August 13th Draft:
The Development Scenario
The development scenario has been developed (in order to evaluate impacts) based on the City's 2020
Comprehensive Plan. The project area includes an area of approximately 624 acres. The AUAR project
area includes all of the land contained in the 2005 expansion of the Metropolitan Urban Service Area
(MUSA). The area is currently used for agricultural purposes, most of it tilled for row crop production.
The only development in the area is the few associated farmsteads and City of Chanhassen Lift Station//24
which is located along Lyman Boulevard at its intersection with the northerly segment of Audubon Road.
The development scenario assessed in this AUAR reflects land uses in more detail than illustrated in the
land use plan of the comprehensive plan. The comprehensive plan identifies multiple land uses that
overlap one another. For example, a site may be identified as either low density residential or medium
density residential. Where land use categories are shown as overlapping in the land use plan, one land use
pattern that would generate the greatest impact while maintaining consistency with the comprehensive plan
was selected. This scenario represents the "worst case" development scenario.
One area to specifically note is the school designation for the site at the intersection of Lyman and
Audubon. This site is guided as Office/Industrial Park/Open Space in the comprehensive plan. As
described earlier, a school facility is a possibility for the site but not certain. For purposes of the AUAR, a
school facility is being used due to the higher traffic impacts. Details of the school site are described
below in the School section and in question 4/21 - Traffic.
The Development Scenario is illustrated in Figure 14.
Replace the School section identified in the "Types and Intensity of Development anticipated within the
AUAR Project Area" on Page 13 of the August 13th Draft:
School--The School designation is not identified as a land use category in the Comprehensive Plan.
However, it appears in the Development Scenario. The Chaska School District (#112) Master Facilities
Plan identifies the need for additional elementary and secondary school sites to address its growing
enrollment. The Chanhassen City Council adopted Resolution # 2003-54 in June of 2003 expressing its
desire to have the District locate a middle or high school facility in the City of Chanhassen. The resolution
is included in Appendix 1. There currently are no schools of this type in the eastern portion of the Chaska
School District. The AUAR project area has been identified as a potential location with access preferably
from Lyman Boulevard. The City also sees the opportunity for a joint School/Park facility. Estimated land
needs for this complex are about 60 to 80 acres. The School District has suggested they would be looking
for a facility that could accommodate up to 1,700 students.
Replace the transportation improvements section on Page 14 of the August 13th Draft:
Transportation Improvements
The transportation chapter of the comprehensive plan identifies several planned roadway improvements
and system deficiencies relevant to the project area. In addition, it is assumed that at least three local
collector roadway features will be necessary within the project area. One that stretches from east to west
across the entire project area connecting Audubon Road with Powers Boulevard; one segment that
Kate Aa~ozso~
August 27, 2003
Page 3
connects the east west collector to Pioneer Trail and a third segment that connects the east west collector
with Lyman Boulevard. A loop road connecting Audubon Boulevard and Lyman Road is shown in
Transportation Analysis Zone (TAZ) 1. Ultimately, this roadway may not to be public under certain
circumstances. The public road alternative is a private drive with the identified connections at Audubon
Boulevard and Lyman Road. Classification and design of this roadway would depend on the type of use
for the site, either office/industrial or school facility. If developed as office/industrial, one or two
businesses may not necessitate a public road. A school facility would probably have private road as well,
with connections at Audubon Boulevard and Lyman Road as identified. An office/industrial area with
more than two businesses would likely need public roadway through that area to better connect uses and
facilitate traffic flow. The following roadway improvements are included in this analysis:
Replace Water Supply Improvements section on Page 15 of the August 13th Draft:
Public Water Supply Improvements
The Comprehensive Plan identifies a future elevated water tower storage site near Lyman Boulevard and
Powers Boulevard and future trunk water main systems generally following the major roadway corridors of
Lyman Boulevard, Audubon Road, Pioneer Trail and the extension of Powers Boulevard. The City is
currently working on an update to the comprehensive water supply and distribution plan. The draft plans
anticipate that the project area may be served by the Central Water Treatment Plant (site 10). If this is the
case, the future elevated water tower may be eliminated.
See Figures 15 and 16 for location of existing and future utility services in the project area.
Replace Storm Sewer Improvements section on Page 15 of the August 13th Draft:
Storm Sewer Improvements
The Chanhassen Surface Water Management Plan (SWMP) was adopted in March 1994. The project area
is located within the Bluff Creek and Lake Susan Storm Drainage Districts. Stormwater improvements
within the project area and outside of the TH 212 right-of-way show the utilization of selected
agricultural/urban wetlands for nutrient traps to improve water quality. Additional areas throughout the site
are designated for stormwater sediment traps and stormwater quantity ponds. However, due to changes in
the Minnesota Wetland Conservation Act (WCA), jurisdictional wetlands can no longer be used for storm
water management without mitigation or an approved comprehensive wetland management plan (which the
City does not have at this time) Sediment traps and water quantity control facilities within the TH 212
right-of-way would handle run-off from portions of the project area. Future stormwater improvements are
likely to include smaller parcel specific stormwater ponds to assure compliance with National Pollutant
Discharge Elimination System (NPDES) Phase II stormwater requirements.
The Surface Water Management Plan includes a conceptual surface water management plan that identifies
locations and sizes of pipes, open channels and ponds to facilitate drainage throughout the AUAR project
area. Although the proposed sizes of the improvements will need additional review in the AUAR
Mitigation Section and at the time of development, they provide a basis for attaining water quality
standards expected by the plan. Stormwater ponds in the project area consist of nutrient traps, sediment
traps, and quality ponds. Because the plan is in need of updating, newer stormwater management
techniques may be considered for mitigation measures as needed.
Portions of the project area drain to and will utilize ponds constructed within the proposed TH 212/312
right-of-way. Stormwater improvements will need to be reviewed with MnDOT to ensure storm water
facilities are properly sized based on the recently revised roadway alignment (August 2003).
Kate Aanenson
August 27, 2003
Page 4
8. PERMITS AND APPROVALS REQUIRED.
Replace Lower Minnesota River Watershed District within Table 8.1 on Page 18 of the August 13th
Draft:
Riley Purgatory Bluff Creek Watershed District
9. LAND USE.
Replace the first paragraph on Page 19 of the August 13a' Draft:
Past and current land use in the project area has been agricultural based uses, mostly row crops.
Six operating farmsteads exist and generally consist of a residential structure and various outbuildings such
as barns, sheds or silos. Two large lot residential estate properties are located in the project area (Figure
11). Private individual septic treatment systems and private wells are utilized by existing uses (Figure 23).
The following table provides a breakdown of existing land use in the project area.
17. WATER QUALITY-STORMWATER RUNOFF.
Replace this section on Page 27 of the August 13tn Draft:
As noted above, City and watershed regulations as well as recently adopted National Pollutant Discharge
Elimination System (NPDES) Phase II regulations (administered by the Minnesota Pollution Control
Agency (MPCA)), establish the standard for surface water conveyance, detention and mitigation for any
development proposed in the AUAR study area. Mitigation requirements include: · Maintaining discharge rates at or below current levels.
· Pre-treatment of runoff prior to discharge to wetlands, in accordance with wetland
classification requirements.
· Conformance to NURP standards.
· Stormwater quality and quantity treatment by site.
City and watershed guidelines, as well as Best Management Practices (BMPs), also promote use of
additional infiltration facilities (such as rain gardens) in new development areas, where feasible, to
decrease runoff volumes and increase groundwater recharge.
Figure 17 illustrates a conceptual surface water management plan for the AUAR study area, including
anticipated drainage sub-areas, flow directions, and locations of nondevelopment specific regional
detention/treatment ponds relative to existing wetland areas. As development plans are refined, developer
and City/watershed staff will work together to refine the storm water management plan, including sizing
and location of ponds and identification of potential additional infiltration areas. This plan will include a
detailed storm water analysis for water quality discharges, including demonstration of conformance to
National Pollutant Discharge Elimination System (NPDES) Phase I1 regulations and City water treatment
standards for total system discharges. The storm plan will also review wetland 'bounce' effects from storm
water discharges as well as assessment of potential storm water impacts on wetland quality.
20. (A) SOLID WASTES;
Revise the notes for Table 20.1 on Page 29 of the August 13th Draft:
Kate Aanenson
August 27, 2003
Page 5
Notes:
1) MSW generation based on 2002 data for the City of Chanhassen from Carver County Environmental Services.
2) Recycling materials generation based on 2002 county-wide data.
3) 2002 Chanhassen population estimate - 21,345 (Metropolitan Council).
4) 2002 Carver County population estimate - 75,312 (Metropolitan Council).
5) 2010 Chanhassen population forecast - 27,000; household forecast - 10,000; 2.7 persons/household (Metropolitan Council).
6) 2010 Carver County population forecast - 95,950; household forecast - 36,020; 2.66 persons/household (Metropolitan Council).
Replace Table 20.2 on Page 29 of the August 13tn Draft:
TABLE 20.2. SUMMARY OF CURRENT AND FUTURE COMMERCIAL WASTE GENERATION
Commercial Waste Current Current Future Future Estimate of
Generation Rates Employment Estimate of Employment MSW/year
Estimate MSW/year Estimate
0 0 tons 2087 3318 tons
1.59 tons of
MSW/employee/year
1.1 tons of
recycling/employee/year
Notes:
0 0 tons 2087 2296 tons
1) MSW generation based on 2002 data for the City of Chanhassen from Carver County Environmental Services.
2) Recycling materials generation based on 2002 county-wide data.
3) Assumes office employment @ 4 employees/1000 square feet and office/industrial employment @ 2.31 employees/1000 square
feet.
Insert a new Table 20.3 after Table 20.2 on Page 29 of the August 13tn Draft:
TABLE 20.3. SUMMARY OF CURRENT AND FUTURE SCHOOL WASTE GENERATION
School Waste Generation Current Current Future
Rates Enrollment Estimate of Enrollment
Estimate MSW/year Estimate
1.59 tons of 0 0 tons 1700
MSW/student/year
1.1 tons of 0 0 tons 1700
recycling/student/year
Notes:
Future Estimate of
MSW/year
2703 tons
1870tons
1) School Facility MSW generation based on 2002 Commercial MSW from Carver County Environmental Services.
2) School Facility recycling materials generation based on 2002 county-wide data.
21. TRAFFIC.
Replace the section after Table 21.1 on Page 32 of the August 13tn Draft:
Trip Generation
A cursory trip generation comparative study was conducted for land uses identified in TAZ 1. The purpose
of this evaluation was to determine the trip generation characteristics between a school and various
different forms of non-residential uses that could be developed on the site. Using land use information
from the ITE Trip Generation Handbook, the study indicates that a school would have daily trip generation
Kate Aanenson
August 27, 2005
Page 6
slightly greater than that of light industrial, manufacturing, or research related (similar to the
Office/Industrial designation in the Comprehensive Plan) land uses. The school does exhibit AM peak
hour characteristics similar to the more intense business park land use. During the PM peak hour,
however, the school generally exhibits slightly less peaking characteristics than the light industrial uses.
If general light industrial, manufacturing, or research uses were placed in TAZ 1 (in lieu of the school)
there would be no change to the mitigation measures outlined in the draft AUAR document for the 2010
horizon year. In addition, given the modified trip distribution characteristics with Highway 212/312, it was
further concluded that even if a business park were developed in TAZ 1 no additional mitigation measures
are necessary. It should be noted, however, that development of a more intense "office" park uses (multi-
story buildings with decked parking for example) may require further traffic mitigation if developed.
22 AND 24. VEHICLE RELATED AIR EMISSIONS AND DUST, ODORS, NOISE.
The full noise and air impact report is included in this packet and will appear in its entirety as appendix 6. A
summary of the major impacts will be incorporated in questions 22 and 24.
28. IMPACT ON INFRASTRUCTURE AND PUBLIC SERVICES.
Replace this section with following:
Municipal Infrastructure Systems
Impacts on sanitary sewer systems, storm sewer systems and public water supply systems as a result of the
projected development outlined in question 6 will be significant but consistent with City planning. The
City has identified in its planning efforts improvements to its municipal infrastructure associated with
anticipated development of the 2005 MUSA area according to the 2020 Comprehensive Plan. Trunk
sanitary sewer will be extended from the Lift Station #24 to serve the land area generally west of the TH
212/312 expansion. A new lift station, force main and trunk sewer will be required to serve the portion of
the project area east of TH 212/312 extension. A water distribution system will be developed to serve
future development in the project area with water supply from the Central Water Treatment Plant (site 10).
No new wells are anticipated. The City SWMP outlines general strategies for managing stormwater.
However, this plan is outdated and should be updated to reflect changes in law regarding the use of
wetlands for storm water management and the recently adopted National Pollutant Discharge Elimination
System (NPDES) Phase II requirements for stormwater management. A strong position on environmental
site design is outlined by existing City polices and ordinances.
APPENDIX 5-TRAFFIC ANALYSIS
A full traffic report will be included as appendix 5 in the next draft
APPENDIX 6-AIR AND NOISE ANALYSIS
The attached report will be included as appendix 6 in the next draft