Item 3.7 - Facility Plan AmendmentOt" TY
F O
MINNESOTA V
DEPARTMENT INFORMATION
Request for
City Council Action
ORIGINATING DEPARTMENT
REQUESTOR:
MEETING DATE:
Utilities
Utility Manager Neidermeier
May 24, 2021
PRESENTER(s)
REVIEWED BY:
ITEM #:
Consent
City Administrator/Finance Director Flaherty
AE2S Engineer Schaefer
3.7
STRATEGIC VISION
MEETS:
I THE CITY OF OTSEGO:
ARE YOU SEEKING APPROVAL OF A CONTRACT?
Is a strong organization that is committed to leading the community through innovative
communication.
X
Has proactively expanded infrastructure to responsibly provide core services.
BAC KG RO U N D/J USTI F I CATI O N:
Is committed to delivery of quality emergency service responsive to community needs and
expectations in a cost-effective manner.
West WWTF Liquid Treatment Improvements. The Otsego Wastewater Master Plan was adopted by
Is a social community with diverse housing, service options, and employment opportunities.
as well as clarifying the intended schedule and other details. Adoption of the amendment formalizes these
Is a distinctive, connected community known for its beauty and natural surroundings.
AGENDA ITEM DETAILS
RECOMMENDATION:
City Staff is recommending that the City Council adopt the Wastewater Facility Plan Amendment.
ARE YOU SEEKING APPROVAL OF A CONTRACT?
IS A PUBLIC HEARING REQUIRED?
No
No
BAC KG RO U N D/J USTI F I CATI O N:
The AE2S/City design team has been progressing through the scoping and preliminary design of the Phase 1
West WWTF Liquid Treatment Improvements. The Otsego Wastewater Master Plan was adopted by
Council in 2018, and the Facility Plan Amendment makes adjustments to the scope of the Phase 1 project
as well as clarifying the intended schedule and other details. Adoption of the amendment formalizes these
items for the Minnesota Pollution Control Agency's review and approval process.
The Public Works Subcommittee was presented with this information at their May 19 meeting, with
recommendation for consent approval by the City Council.
SUPPORTING DOCUMENTS ATTACHED:
0 Technical Memorandum — Facility Plan Amendment
POSSIBLE MOTION
PLEASE WORD MOTION AS YOU WOULD LIKE ITTO APPEAR IN THE MINUTES:
Motion to adopt the Facility Plan Amendment titled "Otsego West WWTF — Liquid Phase 1 Update" dated
May 5, 2021.
BUDGET INFORMATION
FUNDING: BUDGETED:
Fund 602 — Sanitary Sewer Utility Yes
0
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MINNESOTA V
•
Technical Memorandum — Facility Plan Amendment
Otsego West WWTF — Liquid Phase 1 Update
To: Kurt Neidermeier
Utility Manager
City of Otsego
From: Scott Schaefer, PE
AE2S
Date: May 5, 2021
Project No: P05409-2017-004
SUMMARY
The intent of this technical memorandum is to provide an update to the implementation approach
for the West Liquid 1 (WLI) project as previously described in the Otsego Wastewater Master
Plan (2018). Additional refinement will occur through the course of preliminary and final design.
2 PROJECT SCOPE MODIFICATIONS
The WL1 project is essentially intact as described in the Otsego Watewater Master Plan with the
addition of project elements to either make a more complete project or to accelerate project
elements from the West Liquid 2 phase. The project scope is outlined below with new scope
elements indicated in bold.
• Lift Station No. 3 (LS3) Upgrade / Capacity Expansion:
o Originally considered part of the collection system, but the LS3 is located directly
adjacent to the West WWTF and is being included in the WL1 project.
o New Submersible Pumps.
o New Electrical and Controls.
• Existing Preliminary Treatment Building (PTB):
o New Coarse Screening Equipment (6 mm)
o New Vortex Grit Unit, Pump, and Classifier (i.e. improve dewatering of
screenings)
WLl Project Update
City of Otsego, MN P05409-2017-004
Think Big. Go Beyond.J A www.ae2s.com
o Note that there is potential for the PTB function/processes to be consolidated in
WL 1 instead of WL2 as previously planned; this will be further investigated
during preliminary design, particularly relative to phasing, HVAC requirements,
and odor control.
• New Fine Screening Building:
o 2 mm Fine Screens and Conveyance equipment
o Odor Control
o Evaluate the potential for a Jet -Vac off-loading area (internal city use only,
not intended for external septic / hauled waste)
• New Secondary Biological Treatment:
o Anaerobic Zone
o Anoxic Zone
o Aeration Zone
o Post Anoxic Zone
o Membrane Tanks
o Enhanced Nutrient Removal Recycle
• New Membrane Bio -Reactor (MBR) Equipment Building:
o Mixed Liquor Recycle and Waste Sludge Pumping
o Permeate Pumping
o MBR Blowers
o MBR Backpulse System
o Secondary Treatment Aeration Blowers
o Chemical Addition Systems
o Membrane Cleaning Systems
o Air Compressor System
o Review of the benefit of flow equalization for the MBR system performance
and potential inclusion in the project
• UV Disinfection:
o New UV Equipment in Existing Building
• New Effluent Aeration Tank and Building:
o Effluent Aeration Tank and Diffusers
o Effluent Aeration Blowers
o Note that existing oxidation ditch tank(s) will be evaluated for use as effluent
aeration tanks and effluent aeration blowers may be located in the MBR building.
• Reuse Water System
o Booster pumping system
o Disinfectant residual feed
o Piping systems
WL1 Project Update
City of Otsego, MN P05409-2017-004
Think Big. Go Beyond. PJ AE2S www.ae2s.com
• Electrical Improvements
o Power Feed Capacity
o Emergency Power
o Solar (evaluation as part of the B3 process)
• Controls
o System architecture for new and existing controls
o Security improvements
• Site improvements
o Civil
■ Landscape Improvements (Bee Lawn or Native Grass Mix)
■ Access Control (Automated Gate)
■ Yard Piping
o Stormwater Improvements
■ Intent of obtaining / maintaining "no exposure" designation
o Electrical
o Gas
• Related electrical, controls, structural, HVAC, and plumbing improvements
• Required permitting and related activities including an Environmental Assessment
Worksheet and an Anti -Degradation evaluation are anticipated.
• Items moved into WLI, which were previously in WL2 (generally non -process
project elements)
o Administration Building
■ Offices, workstations, computers
■ Lunchroom area
■ Training room
■ Lockers
o Shop
■ Evaluate location / co -location within other buildings (i.e. within MBR
Process Building, Garage, or Administration Building)
■ Size/need
o Garage Space
■ Vehicle parking for a tanker truck plus additional trucks and
equipment (assumed to be the same or larger than the East WWTF
general purpose garage); may be co -located with the Administration
Building
• Additional Notes — Not Included in the Current Project
o The City Council has confirmed the intent to pursue the West Driveway as
discussed in the Master Plan, although the alignment is anticipated to be
WL1 Project Update
City of Otsego, MN P05409-2017-004
Think Big. Go Beyond. PJ AEZS www.ae2s.com
modified once actual conditions and land availability are further
investigated. Assuming the West Driveway is feasible, it will be constructed
as a stand -along project.
o An additional analysis was conducted to determine if an Independent West
Biosolids Facility similar to the currently in -construction East Biosolids
Facility (dewatering plus stabilization) could or should be pursued. Through
the analysis, it was determined that an Independent West Biosolids Facility is
technically feasible, but would substantially increase the capital cost for
biosolids capacity. The decision was made to reserve space on the West
WWTF site such that the option of an independent facility would remain
available, but the Master Plan biosolids phasing approach has been
confirmed as the baseline.
3 PHASING
The phasing of the West Liquids projects has been previously described in the Wastewater
Master Plan (2018). An additional study of the City's collection system was conducted in 2020-
2021, which resulted in some minor adjustments to the Ultimate Buildout flows between the East
and West WWTFs.
The remainder of the page is intentionally blank.
WL1 Project Update
City of Otsego, MN P05409-2017-004
Think Big. Go Beyond, fJ AEs www.ae2s.com
Table 1: Updated West WWTF Liquids Phasing
Units Phase 1 Ultimate
[MGD]
1.41
4.2
[ppd]
3,183
9,442
mg/L
270
270
[ppd]
3,607
10,730
mg/L
306
306
[ppd]
460
1,373
mg/L
39
39
[ppd]
130
326
mg/L
11
9
5.2
11,695
270
13,923
321
1,982
46
467
11
5.6
18,913
405
21,607
463
3,204
69
835
18
WL1 Project Update
City of Otsego, MN P05409-2017-004
Think Big. Go Beyond. A www.ae2s.com
4 COST UPDATES
The 2018 Wastewater Master Plan (adopted January 2018) included costs in 2017 dollars. The
current project schedule includes a 2022 bidding and 2022 to 2023 construction timeframe. Costs
were adjusted to 2020 dollars during project scoping in late 2020, and additional detail/scope has
been included in the opinion of cost that has resulted in an updated opinion of cost of
approximately $30,080,000 as indicated in Table 1.
Table 2: U
inion of Project Cost
Mobilization
$1,402,000
Site Work
$1,247,000
Influent Pump System (*)
$300,000
Preliminary Treatment Building
$1,404,000
Convert Existing OD to Anaerobic Selector
$348,000
MBR
$9,325,000
Tertiary Treatment Building/ UV
$272,000
Effluent Aeration
$546,000
Administration Building (*)
$1,650,000
PTB Biofilter Odor Control
$313,000
Electrical
$2,311,000
Mechanical
$1,232,000
Instrumentation and Controls
$1,078,000
am-,
000
Construction Contingencies
$2,678,000
Undeveloped Construction Details +
$1,607,000
Engineering, Legal, Admin
(*) Not previously in WI -1 in Master Plan
It should be noted that the post -pandemic construction market appears to be experiencing
significant inflation (materials and labor) and that the impact of stimulus funds on construction
pricing remains uncertain. These additional inflationary pressures are not yet accounted for in
Table 2.
WLl Project Update
City of Otsego, MN P05409-2017-004
Think Big. Go Beyond.] AEs www.ae2s.com
5 SCHEDULE
The following is a projected project schedule:
• Preliminary Design January -June 2021
• MBR Pre -Procurement April 2021
• 60% Design
• 90% Design
• Final Design
• Bidding
• Construction Initiation
• Substantial Completion
• Final Completion
July -November 2021
November 2021 — February 2022
March -April 2022
May 2022
June 2022
November 2023
December 2023
WL1 Project Update
City of Otsego, MN P05409-2017-004
Think Big. Go Beyond. PJ AU -5 www.ae2s.com