HomeMy WebLinkAboutMorningside_Flood_Infrastructure_Technical_Memo_Feb2021
Barr Engineering Co. 4300 MarketPointe Drive, Suite 200, Minneapolis, MN 55435 952.832.2600 www.barr.com
Memorandum
To: Jessica Wilson and Ross Bintner, City of Edina From: Cory Anderson, Greg Williams, and Sarah Stratton Subject: Infrastructure Options to Reduce Flood Risk in the Morningside Neighborhood Date: February 3, 2021 Project: 23271798.00
1.0 Purpose of Project and Project Background
This technical memorandum summarizes Barr Engineering Co.’s (Barr’s) evaluation of the refined potential
options for flood risk reduction in the Morningside neighborhood within the City of Edina (Figure 1). This
evaluation expanded on previous efforts briefly summarized in Section 2.0. The flood risk reduction
features of the refined options are described in Section 3.0. The benefits and the associated costs of each
of the refined options are discussed in Section 4.0, and Section 5.0 describes some tradeoffs and
opportunities that may exist for
further refinement ahead of final
detailed design and construction.
Finally, conclusions of this work
and the previous efforts and a
summary of recommended next
steps are included in Section 6.0.
The goal of this memo is to provide
City staff and City Council with the
information needed to make
decisions in 2021 aimed at
implementing the most
economical, advantageous, and
optimized flood risk reduction
project in the Morningside
neighborhood in coordination with
the planned street reconstruction
in 2022 and 2023.
The City has also performed
extensive community engagement
to address flood risk reduction options in the Morningside neighborhood. These efforts are described in a
separate report.
Figure 1 Morningside Neighborhood study area (storm sewer shown in black lines)
To: Jessica Wilson and Ross Bintner, City of Edina From: Cory Anderson, Greg Williams, and Sarah Stratton Subject: Infrastructure Options to Reduce Flood Risk in the Morningside Neighborhood Date: February 3, 2021 Page: 2
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2.0 Summary of Previous Work
The City of Edina’s Comprehensive Water Resources
Management Plan (CWRMP), published in July 2018
(reference (1)) identified the Morningside neighborhood as
an area with a significant number of structures at risk of
flooding. This neighborhood is also planned for street
reconstruction in 2022 and 2023 (reference (2)). Given both
the need to reduce flood risk and the street reconstruction
opportunity, the City began planning for a flood risk
reduction project. At the time the CWRMP was published, an
uncalibrated stormwater model of the City was used to
determine the main factors affecting flood risk. These factors
were identified as limited outlet capacity from the
Morningside neighborhood to Minneapolis and limited flood
storage capacity within the neighborhood. A preliminary
analysis was completed to understand options available to
reduce peak water levels during storm events and to assess
the impact of each potential flood risk reduction option.
Ultimately, the suggestions documented in the CWRMP
included increased flood storage in Weber Park, increased
outlet capacity to Bde Maka Ska (in coordination with
Minneapolis), and increased pipe capacity and additional or
new stormwater outlets within the neighborhood.
In November 2018, the uncalibrated stormwater model was
used to conduct a more detailed assessment of the options
for reducing the flood risk identified in the CRWMP
(reference (3)). In this evaluation, flood risk reduction
scenarios (i.e., surface storage, conveyance, underground
storage, pumping, etc.) were initially analyzed, one at a time,
to understand the impacts of each type of approach and
identify the locations in the neighborhood that would receive
the most flood risk reduction benefit. Individual components
of each flood risk reduction scenario were then grouped into
multiple “combination options” to further increase flood risk
reduction benefits. Additionally, a method was developed to (1) estimate potential flood damage (in
dollars) to individual homes and to the neighborhood as a whole, and (2) estimate the value of each flood
risk reduction option (in dollars of potential damage avoided). The study included planning-level opinions
Timeline of Previous Related Work
2018
• City of Edina Comprehensive Water Resources Management Plan developed
• Uncalibrated Morningside neighborhood stormwater model used to assess feasibility of preliminary options for reducing flood risk
2019
• Morningside surface water levels monitored and used to calibrate existing stormwater model in cooperation with St. Louis Park and Minneapolis
• City engages a citizen task force to help inform a flood risk reduction strategy 2020
• City publishes a Flood Risk Reduction Strategy
• Updated stormwater model used to evaluate design storm events; resulting flood risk documented
• Local engineering experts in urban/residential flooding and mitigation meet to further evaluate existing flood risk reduction concepts and discuss new and modified approaches
• Calibrated and detailed stormwater model used to model the best subset of flood risk reduction scenarios
• “Refined options” are created that maximize the flood risk reduction benefit to the neighborhood while considering a range of estimated costs
To: Jessica Wilson and Ross Bintner, City of Edina From: Cory Anderson, Greg Williams, and Sarah Stratton Subject: Infrastructure Options to Reduce Flood Risk in the Morningside Neighborhood Date: February 3, 2021 Page: 3
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of construction costs for comparison to the estimated value of each flood risk reduction option (i.e.,
benefit-cost analysis). This analysis showed:
1) Additional flood storage volume is necessary in this neighborhood.
2) Increased pipe capacity benefits the upstream (south and west) portions of the neighborhood and
is only possible if increased flood storage volume is also included.
3) Pumping is one way to create additional flood storage volume.
4) Adding a predictive component to the pumping increases the cost by a relatively small amount
(approximately 1% of the overall cost estimate, or about 10% of the pump station alone).
5) Although it can provide significant storage, underground storage is not economical.
It was during this study that the option for a larger outlet pipe to Minneapolis was removed from
consideration because it would exacerbate existing flooding concerns within Minneapolis.
Evaluations up to this point were completed using an uncalibrated stormwater model. In 2019 the
hydrology and hydraulics of the neighborhood were studied in more detail by monitoring surface water
levels and then using the data to calibrate the stormwater model to multiple storm events. The model was
also combined with the stormwater models of the adjacent cities of St. Louis Park and Minneapolis to
further reduce uncertainties associated with model boundary conditions. Finally, additional overland flow
detail (two-dimensional modeling of water on the ground surface) was added to the model to improve
the understanding of surface flow during large storm events. The updated model was used to model
design storm events (from the 20%-annual-chance event through the 0.2%-annual-chance event), and the
resulting flood risk was documented in April 2020 (reference (4)).
In 2020, City staff convened two meetings of local engineering experts in urban/residential flooding and
mitigation to further evaluate existing flood risk reduction concepts and discuss new or modified
approaches. For this meeting, a modified version of an Estimate-Talk-Estimate (ETE) approach was used—
a problem was presented, and multiple rounds of thoughts and opinions shared until consensus was
reached. These meetings helped confirm that there are three primary approaches to reducing flood risk in
this area (reference (5)):
1) Increase conveyance to move water away from people and structures
2) Increase storage to hold water away from people and structures
3) Move people and structures away from water to reduce exposure and/or reduce structure
vulnerability
To: Jessica Wilson and Ross Bintner, City of Edina From: Cory Anderson, Greg Williams, and Sarah Stratton Subject: Infrastructure Options to Reduce Flood Risk in the Morningside Neighborhood Date: February 3, 2021 Page: 4
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The three primary approaches confirmed during these meetings were consistent with the previous work
described above; however, there was no detailed discussion about where to use these general approaches
within the Morningside neighborhood.
Also in 2020, the calibrated two-dimensional stormwater model was used to model the best subset of the
flood risk reduction scenarios created in 2018. This was an effort to update our understanding of the
benefit of these scenarios (compared to the existing flood risk) using the best available model (reference
(5)). The main conclusions from the 2018 analysis were confirmed and the modeling highlighted the
increased benefit of combining features best suited for different portions of the neighborhood.
At the end of 2020, “refined options” were created that maximize the flood risk reduction benefit to the
neighborhood while considering a range of estimated costs (Section 3.0). Throughout this process, every
effort was made to avoid relying on acquisition of homes to reduce exposure to flood risk.
In 2020, the City also developed a Flood Risk Reduction Strategy (reference (6)) that included a summary
of actions that homeowners can take to reduce their vulnerability to flooding. This information, along
with other information related to flooding and drainage, is available on the City’s website (reference (7)).
3.0 Description of the Refined Options
Refining flood risk reduction options requires a “balancing act.” For example, while using larger pipes to
increase conveyance may reduce flood risk in the upstream portion of the watershed, it can also push the
problem downstream. To mitigate the effect of increased upstream conveyance, increased storage
downstream is required. In short, we need to take care that flood risk reduction measures do not simply
transfer risk from one area of the watershed to the other. In addition to achieving balance, an additional
goal for refined flood risk reduction options was that flood risk should not increase for any structure.
The effort to refine flood risk reduction options was informed by the previous work described in Section
2.0 and summarized below:
• Additional flow capacity out of the neighborhood to Minneapolis should be removed from
consideration. While adding flow capacity using larger pipe will effectively decrease risk in
upstream areas, it also transfers that risk to downstream areas—where conveyance capacity does
not exist. There are existing and significant flooding issues present in Minneapolis between the
Morningside neighborhood and Bde Maka Ska, and on the lake itself.
• Additional flood storage in the Morningside neighborhood is necessary. Additional flood
storage not only serves those who live closest to it by reducing local water levels, but also makes
it possible to increase conveyance from upstream areas to the areas with additional storage.
Without additional flood storage, additional conveyance merely transfers risk from upstream to
To: Jessica Wilson and Ross Bintner, City of Edina From: Cory Anderson, Greg Williams, and Sarah Stratton Subject: Infrastructure Options to Reduce Flood Risk in the Morningside Neighborhood Date: February 3, 2021 Page: 5
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downstream. Increasing flood risk to individual downstream structures is not an acceptable
outcome.
• The additional flood storage needed should be placed in open areas located at the surface
(i.e., not underground), near the mid- and downstream portions of the neighborhood. The
result is a few large, concentrated pond features in the neighborhood. The upstream portions of
the neighborhood are fully developed with no room for large surface storage, and underground
storage is not a cost-effective solution here.
• A moderately sized pump station can be added to the neighborhood and can provide
substantial available storage in advance of large storms by pumping down the ponds in a
controlled manner (i.e., predictive pumping). Using pumping to pre-emptively increase
available storage can allow greater effective storage within a smaller footprint. Predictive ability
(monitoring weather forecasts and water levels in real-time) can be added for little additional cost
and automates the operation of this feature.
• Increased conveyance capacity via storm sewer pipes is necessary to reduce upstream
flooding and limit surcharging and overland flow in the mid-to-downstream areas. The
main storm sewer lines through the neighborhood flow above full capacity during large storms,
which results in water spilling out of the storm sewer into the streets and onto the surface
(surcharging). Increased conveyance can transfer risk from upstream to downstream if there is
insufficient storage capacity downstream; thus, increased conveyance must be balanced with
increased storage volume.
• Flood risk in backyard areas that lack or do not have sufficient storm sewer outlets can be
reduced by adding catch basins or similar structures. However, this can only be done if the
capacity of the connected storm sewer lines is increased to accommodate the additional water.
Ultimately, this can only be done if additional flood storage volume is provided downstream.
• Individual home and property owners can and should take preventative measures to further
reduce flood risk to themselves. One of the approaches for reducing flood risk is to limit
exposure and/or vulnerability. As homes are rebuilt in the City, policies regarding minimum
building elevations may reduce exposure and therefore flood risk. Additionally, features such as
backflow preventers, tile drain around homes, and backup generators reduce vulnerability and
risk (reference (8)). The City’s Flood Risk Reduction Strategy included a tool kit that provide
residents with a range of ideas (including low-cost and no-cost options) to reduce the
vulnerability of their homes, such as storing valuable items off the basement floor, redirecting
downspouts and taking temporary mitigation measures when rains are anticipated.
A refined combination option was created based on the bullet points above. The initial concept was
intended to achieve as much flood risk reduction as possible, while avoiding options previously ruled out
(e.g., increasing flow to Minneapolis, acquisition, avoiding unrealistically sized infrastructure). The
To: Jessica Wilson and Ross Bintner, City of Edina From: Cory Anderson, Greg Williams, and Sarah Stratton Subject: Infrastructure Options to Reduce Flood Risk in the Morningside Neighborhood Date: February 3, 2021 Page: 6
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probable cost was estimated for construction and design (~$15M, “Biggest” option) and identified to be
higher than the anticipated funding available. Therefore, the refined combination option was modified by
removing features that were less beneficial (compared to their individual cost) until the costs were
lowered to levels closer to the available-funding estimate provided by City staff (~$5M, “Big” option) and
about double that value (~$10M, “Bigger” option).
The following numbered list describes each of the individual flood risk reduction features in the refined
options. Figure 2 shows the locations of those features identified using the numbers from the list below.
Table 1 identifies which features are included at the three different estimated cost levels. Additional
information is available in the published documents on the City’s Better Together website, particularly
documents related to the December 2020 virtual public meeting (reference (9)).
1) The first feature is an expanded Weber Pond, creating some of the necessary additional flood
storage in the downstream-most portion of the neighborhood. The proposed pond is larger in
extent, expanding into Weber Woods and slightly west into Weber Park. The pond bottom is
lowered, and the outlet elevation of the pond is also lowered by creating a lower gravity outlet, or
a pumped outlet, which creates more vertical flood storage capacity before water levels reach
homes or other infrastructure. This feature also includes a pump station with predictive pumping
capabilities to draw the level of the pond down by as much as 3 feet in advance of large storm
events. The pump will not pump the pond fully dry, leaving at least 1 foot of water prior to very
large storm events. Predictive pumping introduces an element of operational uncertainty; the
potential impacts of predictive pumping scenarios were evaluated and summarized in Table 2 of
(reference (5)). The expanded pond requires the removal of a portion of the existing Weber
Woods. Recognizing that these woods are a valued neighborhood amenity, the intent is to keep
them accessible via a bridge over the pond that connects walking paths and enhances the park.
There is also an opportunity to improve the wildlife habitat and restore some ecological integrity.
The preliminary assessment indicates that Weber Woods is a “D” quality lowland forest, close to
classification as an altered/non-native forest/woodland. The canopy is mostly second-growth
cottonwoods, with some box elder, Siberian elm, and American elm. The shrub layer comprises
mostly invasive species or weedy natives, and the ground layer is mostly bare.
This feature is a foundational component of all refined options due to the significant need for
additional storage, although the impact to Weber Woods is smallest in the “Big” refined option and
includes pumped outlets in the ”Bigger” and ”Biggest” refined options.
2) The second feature is a surface swale through Weber Park, between existing park features
(tennis court, baseball and softball fields, etc.). The proposed swale extends from Grimes Avenue
to the expanded Weber Pond, conveying surface flow from the west to the pond in a controlled
manner. The swale can double as a walking path in normal conditions and will be used to convey
flows during large storm events, such as those with less than a 10% chance of occurring annually.
To: Jessica Wilson and Ross Bintner, City of Edina From: Cory Anderson, Greg Williams, and Sarah Stratton Subject: Infrastructure Options to Reduce Flood Risk in the Morningside Neighborhood Date: February 3, 2021 Page: 7
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This feature is not used in the “Big” refined option and is used in the “Bigger” and “Biggest” refined
options. The design of this feature must be considered in conjunction with the design of feature #9,
as both features increase conveyance and have different sizing constraints.
3) The third feature is a large box culvert conveying flow from the open space area between Lynn
Avenue and Kipling Avenue to the storm sewer at the intersection of Grimes Avenue and the W
41st Street corridor. This box culvert could be installed parallel to the existing storm sewer but will
more likely replace the existing storm sewer in that location due to space constraints. In normal,
low-flow conditions, the box culvert will convey water to the existing storm sewer at Grimes
Avenue and the W 41st Street corridor, and water will continue to flow through the storm sewer
out to Minneapolis. During larger storm events, the large box culvert will convey significantly
more flow than the current storm sewer pipes in that location and will discharge excess flow into
the proposed swale in Weber Park (again for large events with less than a 10% chance of
occurring annually). This box culvert is also intended to relieve the flow that would occur over
Kipling Avenue and then overland between homes to Grimes Avenue.
This feature is not used in the “Big” refined option and is used in the “Bigger” and “Biggest” refined
options.
4) The fourth feature is an expansion and lowering of the current open space area between
Lynn Avenue and Kipling Avenue. This open space is periodically inundated by stormwater. The
current normal water level is controlled by the two storm sewer outlets available in the northwest
and northeast corners. These outlets will be reconstructed so that the outlet control level is
lowered by about 3 feet. Additionally, dredging and clearing of vegetation may be done to create
more storage capacity. The City recognizes that the trees along the perimeter of this inundation
area have value, offering a wooded and more natural appearance to this open area. Therefore, the
outer perimeter of trees will be partially left intact to maintain the appearance from the street and
for residents living along Lynn Avenue and Kipling Avenue. The area also has the potential to be
improved for natural resource and wildlife habitat. The final design should consider expanding
these benefits through natural resource restoration.
This feature is used in all three of the refined options.
5) The fifth feature is a large box culvert conveying flow from open park space (Yale Gardens
Park) west of Monterey Avenue to the expanded and lowered inundation area between Lynn
Avenue and Kipling Avenue. This box culvert could be installed parallel to the existing storm
sewer but may end up replacing the storm sewer in that location instead due to space constraints.
In normal, low-flow conditions, the box culvert will not carry significant flow or may not carry flow
at all because the open space west of Monterey Avenue is intended to store and infiltrate water
(feature #6). During larger storm events (those with less than a 4% chance of occurring annually)
To: Jessica Wilson and Ross Bintner, City of Edina From: Cory Anderson, Greg Williams, and Sarah Stratton Subject: Infrastructure Options to Reduce Flood Risk in the Morningside Neighborhood Date: February 3, 2021 Page: 8
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the large box culvert will convey flow into the expanded and lowered open space area between
Lynn Avenue and Kipling Avenue. This box culvert is also intended to eliminate the overland flow
that would occur over Monterey Avenue on the surface between homes towards Lynn Avenue.
This feature is only used in the “Biggest” refined option.
6) The sixth feature is an engineered, lowered, open field on the Susan Lindgren School
property west of Monterey Avenue. This area currently stores some flood water during large
storm events, but storage is limited due, in part, to a rise in the ground elevation in the northeast
corner. This feature will require leveling and lowering the field by 2 to 3 feet and enhancing the
drainage of the field. With this feature, the annual chance that the existing storm sewer pipe that
runs under this space, carrying water from St. Louis Park into Edina, would surcharge is about 20%
or less. During smaller storm events, the field would drain quickly and be usable as open park
space.
This feature is only used in the “Biggest” refined option.
7) The seventh feature is a cleared space to create additional surface storage on the Avail
Academy School Property. Consisting largely of trees, there is some flood storage available in
this area. The trees would be cleared in the interior of this area, the ground would be lowered by
about 5 feet, and the area would be connected via buried storm sewer pipe to the expanded
Weber Pond. This area would be inundated with water as the water level in Weber Pond rises
above an elevation of approximately 859 feet (during events with a less than 20% annual chance
of occurring). Because of the connection to Weber Pond, this area would stay inundated for a
long period of time (likely greater than 48 hours). Additionally, the proposed storm sewer pipes
along Inglewood Avenue (feature #8) would discharge to this area during larger storm events—
those with a 10% or less annual chance of occurring.
This feature is only used in the “Biggest” refined option.
8) The eighth feature is improved conveyance along W 40th Street, Grimes Avenue, and new
conveyance under Inglewood Avenue. Surface flow in the street along W 40th Street carries
some flow from St. Louis Park and some flow from portions of the neighborhood north of W 40th
Street. Currently, a significant portion of that water flows south along the surface of Monterey
Avenue, Lynn Avenue, and Kipling Avenue towards the open space area between Lynn Avenue
and Kipling Avenue and the storm sewer along the W 41st Street corridor. This feature would
increase the pipe capacity along W 40th Street; limit the overland and street flow south on
Monterey Avenue, Lynn Avenue, and Kipling Avenue via modified street grade; and add storm
sewer pipes under Inglewood Avenue. Runoff during low flows and smaller storm events would
be carried entirely by storm sewer pipe to the intersection of Grimes Avenue and Inglewood
Avenue and then out to Minneapolis via the new pipes under Inglewood Avenue, bypassing the
To: Jessica Wilson and Ross Bintner, City of Edina From: Cory Anderson, Greg Williams, and Sarah Stratton Subject: Infrastructure Options to Reduce Flood Risk in the Morningside Neighborhood Date: February 3, 2021 Page: 9
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expanded Weber Pond. Larger storm events would result in street flow down Grimes Avenue,
ultimately contributing to the storm sewer discharging to Weber Pond and the surface swale
through Weber Park.
This feature is only used in the “Biggest” refined option.
9) The ninth feature is increased capacity in the existing storm sewer along W 42nd Street and
along a portion of Crocker Avenue (feature #9) and additional capacity along Crocker
Avenue to Morningside Avenue, serving homes around Branson Street and Morningside
Road (feature #9a). The additional capacity (from larger diameter pipe, and in some cases, where
possible, a steepened pipe slope) serves the upstream and midstream portions of the
neighborhood by increasing conveyance and moving water away from these areas and by limiting
surcharging water nearer to the midstream and downstream areas. The additional capacity also
potentially allows for adding stormwater outlets to backyard areas that currently do not have
outlets, such as the area west of Crocker Avenue and south of W 42nd Street. The additional
capacity along W 42nd Street also allows for a stormwater outlet from the southeast corner of the
open space area between Lynn Avenue and Kipling Avenue, further benefiting the homes in that
area. In addition, proposed localized grading (within the street right-of-way) may be needed in
low areas on the west side of Crocker Avenue to prevent water from overflowing from the street
into backyards. The portion of this feature along W 42nd Street and extending south along a portion
of Crocker Avenue (feature #9) is used in all three of the refined options. This is one of the more
costly features of the refined options. Therefore, only the $10M and $15M cost options include
increased pipe capacity that extends farther south to Morningside Road (feature #9a).
10) The tenth feature consists of disconnecting storm sewer pipe at Scott Terrace from storm
sewer pipe to the west along W 42nd Street. In the existing condition, the storm sewer pipe
under W 42nd Street is under capacity and carries such significant flow that it surcharges,
increasing the flood risk to homes near Scott Terrace and W 42nd Street. The storm sewer pipe to
the west under W 42nd Street is disconnected and rerouted to Weber Pond under the southeast
corner of Weber Park. The increased capacity under W 42nd Street (feature #9) also helps with the
flooding in this intersection by limiting surcharge.
This feature is used in all three of the refined options.
11) The eleventh feature consists of modifications within Weber Park, in particular to the sports
fields. The baseball and softball fields would all be lowered by an average of about 7 feet, and
the drainage would be enhanced. The northeast softball field would be mirrored to the southwest
corner to make room for the swale (feature #2). The annual chance that this area would be used
for temporary flood storage is about 10% or less, and the area would be inundated for less than
24 hours. The area closer to Grimes Avenue would also be leveled, lowered by about 5 feet on
To: Jessica Wilson and Ross Bintner, City of Edina From: Cory Anderson, Greg Williams, and Sarah Stratton Subject: Infrastructure Options to Reduce Flood Risk in the Morningside Neighborhood Date: February 3, 2021 Page: 10
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average, and the ice rink would be rebuilt in a new configuration to make room for the park
swale. This area would be used for temporary flood storage during events with a less than 2%
annual chance of occurring and is estimated to be inundated for less than 12 hours.
This feature is only used in the “Biggest” refined option.
There are other locations throughout the neighborhood where some localized grading may be required to
prevent overflow from the streets into private parcels, particularly into backyards. Locations that have
been identified through modeling (based on LiDAR elevation data) are: near the intersection of Grimes
Avenue and Inglewood Avenue, along Little Street near Lynn Avenue, along Grimes Avenue, Alden Drive,
and Scott Terrace all south of W 42nd Street, the north side of W 42nd Street near Kipling Avenue, and
finally along Branson Street, west of Grimes Avenue. These areas may require slightly higher curbs and/or
surface grading near the streets to ensure that the stormwater flow stays in the streets during large storm
events.
Table 1 Summary of individual flood risk reduction features included in the refined options at the three different cost levels
Feature Number Feature Description “Big” (~$5M) “Bigger” (~$10M) “Biggest” (~$15M)
1 Expanded Weber Pond and Pump Station1 X X X
2 Surface swale through Weber Park X X
3 Large box culvert from Kipling to Grimes X X
4 Open space area between Lynn and Kipling X X X
5 Large box culvert from Monterey to Lynn X
6 Open field on Susan Lindgren School property west of Monterey X
7 Avail Academy property surface storage X
8 Improved conveyance along W 40th Street, Grimes, and Inglewood X
9 Increased storm sewer capacity along W 42nd Street and north portion of Crocker Avenue X X X
9a Increased storm sewer capacity extending south along Crocker Avenue and additional capacity around Branson and Morningside Road X X
10 Disconnecting storm sewer at Scott Terrace X X X
11 Modifications to sports fields within Weber Park X
1 In the “Big” refined option, the Weber Pond expansion into Weber Woods is smaller and does not include a pump station.
To: Jessica Wilson and Ross Bintner, City of Edina From: Cory Anderson, Greg Williams, and Sarah Stratton Subject: Infrastructure Options to Reduce Flood Risk in the Morningside Neighborhood Date: February 3, 2021 Page: 11
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Figure 2 Flood risk reduction features of the refined options (see numbered list and Table 1)
Inundation mapping is provided in Attachment B for the ~$15M refined option, in Attachment C for the
~$10M refined option, and Attachment D for the ~$5M refined option.
Figure 3 and Figure 4 show the incremental flood storage volume that is gained by layering several
components of the flood risk reduction options for both the Weber Pond area and the open space area
between Lynn Avenue and Kipling Avenue, respectively.
To: Jessica Wilson and Ross Bintner, City of Edina From: Cory Anderson, Greg Williams, and Sarah Stratton Subject: Infrastructure Options to Reduce Flood Risk in the Morningside Neighborhood Date: February 3, 2021 Page: 12
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Figure 3 Incremental flood storage volume gained at Weber Pond with various flood risk reduction options
Figure 4 Incremental flood storage volume gained with various flood risk reduction options at the open space area between Lynn Avenue and Kipling Avenue
0
10
20
30
40
50
60
70
80
90
100
Total Flood Storage Volume Available (acre-feet)Incremental Flood Storage Gained at
Weber Pond with Various Options
Previous Increment(s)This Increment
Existing flood
storage volume available between
the normal water level of Weber
Pond and the
lowest adjacent
home
+ Expand
Weber Pond
2 acres into Weber
Woods
+ Expand
Weber an
additional 3
acres into
Weber
Woods and Weber Park
+ Lower expanded
Weber Pond 2.5 feet below
normal water
level using a
pump station
+ Lower
expanded
Weber Pond
an additional 3
feet prior to storm using
predictive pumping
0
5
10
15
20
25
30
Total Flood Storage Volume Available (acre-feet)Previous Increment(s)This Increment
Existing flood storage
volume available
between the normal
water level and the
lowest adjacent
home
+ Expand storage
area by 3 acres
+ Lower the controlling outlet elevation
and normal water level by 3 feet
To: Jessica Wilson and Ross Bintner, City of Edina From: Cory Anderson, Greg Williams, and Sarah Stratton Subject: Infrastructure Options to Reduce Flood Risk in the Morningside Neighborhood Date: February 3, 2021 Page: 13
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4.0 Benefits and Costs
Barr and City staff developed a method to estimate flood
damages based on the peak flood elevations and approximate
home elevations. The method is detailed in the City’s 2018
analysis (reference (10)) and summarized in the sidebar. The
goal of the analysis was to estimate flood risk and associated
impacts at a neighborhood-scale for varying storm events with
and without flood risk reduction options. The flood damage
estimates reflect “loss potential” in dollars, based on estimated
flood loss potential tables published by the Federal Emergency
Management Agency (FEMA) (reference (11)) and assumptions
or judgments about the probability of damage given a flood
level relative to the home elevations. Home elevations were
based on surveyed basement or first-floor elevations for about
half of the homes and estimated from LiDAR-based (elevation
data) adjacent grades for the other half of homes using the
process documented in reference (10).
On an individual home-by-home basis we expect some results
to be underestimated and some to be overestimated.
However, at the neighborhood scale, we believe that the
estimate of total damages is comparable to the level of
confidence in the planning-level costs developed for each
option. As the City’s flood risk reduction effort continues and
surveyed elevations of homes are collected, the analysis can
be updated with more accurate elevation information and
subsequently improve the damage estimates on both a home-
by-home and neighborhood-wide basis. Additionally, as more
information about storm sewer connections or rebuilt homes
is shared and learned, the estimates of the number of homes
impacted and the total damages in dollars is improved.
Table 2 shows the number of structures at risk during each of the storm events modeled, up to the 1%-
annual-chance event.
Table 3 shows the annualized, monetized damage of each condition (existing and with a flood risk
reduction option), the annualized monetary benefit of each flood risk reduction option, and the number
of structures at risk, removed from risk, and where risk was reduced. The annualized, monetized damage
and benefit considers all of the storm events modeled and the probability of those events occurring.
The City’s method estimates an annualized flood
damage for each structure with consideration for
three potential modes of flooding for each
structure:
1) Indirect (floodwater against the foundation)
2) Direct (floodwater over the foundation)
3) Sanitary sewer backup
A curve is developed for each structure
correlating water surface elevation (WSEL) and
estimated damage (or “potential loss”). Damages
are estimated according to the mode of
flooding, severity (i.e., flood depth), structure
footprint, and unit area.
An annualized damage estimate is generated for
each property by integrating the estimated
damage at a given WSEL multiplied by the
annual exceedance probability between the 5-
year and 100-year events, as shown:
The benefit of a flood risk reduction action is
estimated as the difference in the annualized
damage estimates using pre- and post-
mitigation water surface elevations between the
20%-annual-chance event and the 1%-annual-
chance event.
To: Jessica Wilson and Ross Bintner, City of Edina From: Cory Anderson, Greg Williams, and Sarah Stratton Subject: Infrastructure Options to Reduce Flood Risk in the Morningside Neighborhood Date: February 3, 2021 Page: 14
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Table 2 Summary of the number of structures with potential damage by any of the three modes of damage (direct surface water, indirect groundwater, or sanitary backup)
by storm event up to the 1%-annual-chance event (ACE) [100-year event]
Condition 5-year 20% ACE 10-year 10% ACE 25-year 4% ACE 50-year 2% ACE 100-year 1% ACE 500-year 0.2$ ACE
Existing 95 107 115 126 139 160
“Big” 80 94 103 116 134 154
“Bigger” 76 80 84 95 111 141
“Biggest” 76 80 82 89 102 133
Table 3 Summary of assessment of potential damages and impacts to structures
Condition Annualized Damage, $ Annualized Benefit, $
# of Structures with Risk Removed
# of Structures with Risk Reduced
# of Structures with Risk Increased
# of Structures with Risk Added
Total Structures at Risk of Flood Damage
Existing $362,600 --- --- --- --- --- 160
“Big” $260,400 $102,200 6 106 0 0 154
“Bigger” $190,100 $172,500 19 138 0 0 141
“Biggest” $181,800 $180,800 27 139 0 0 133
Table 4 Summary of the potential neighborhood-wide damages in dollars due to flooding by
storm event up to the 1%-annual-chance event (ACE) [100-year event]
Condition 5-year 20% ACE 10-year 10% ACE 25-year 4% ACE 50-year 2% ACE 100-year 1% ACE
Existing $1,037,000 $1,588,000 $1,999,000 $2,349,000 $3,003,000
“Big” $703,000 $1,149,000 $1,413,000 $1,898,000 $2,712,000
“Bigger” $661,000 $838,000 $1,081,000 $1,261,000 $1,617,000
“Biggest” $660,500 $828,500 $995,600 $1,185,000 $1,391,000
To: Jessica Wilson and Ross Bintner, City of Edina From: Cory Anderson, Greg Williams, and Sarah Stratton Subject: Infrastructure Options to Reduce Flood Risk in the Morningside Neighborhood Date: February 3, 2021 Page: 15
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Table 5 Summary of the neighborhood-wide benefits (reduction in damages) in dollars by storm event up to the 1%-annual-chance event (ACE) [100-year event]
Condition 5-year 20% ACE 10-year 10% ACE 25-year 4% ACE 50-year 2% ACE 100-year 1% ACE
Existing --- --- --- --- ---
“Big” $334,000 $439,000 $586,000 $451,000 $291,000
“Bigger” $376,000 $750,000 $918,000 $1,088,000 $1,386,000
“Biggest” $377,000 $759,000 $1,003,000 $1,164,000 $1,612,000
The estimates of damages neighborhood-wide (Table 4) and the benefits (Table 5) are not the annualized
damages and benefits, but the estimated total (in dollars) for particular storm events (20%-annual-chance
event through 1%-annual-chance event). They show the total neighborhood-wide estimated damage
(dollars) and benefit (reduction in damages in dollars) for each of the listed storm events.
An Engineer’s planning-level opinion of probable construction cost had been developed for each of the
previous flood risk reduction options (reference (3) and (5)). The costs were updated to reflect the three
levels of the refined options (“Big,” “Bigger,” and “Biggest”) and are included as Attachment E. The
planning-level opinions of probable construction cost are intended to aid in evaluating and comparing
flood risk reduction options and should not be assumed as absolute values for each option. These
opinions of probable cost generally correspond to standards established by the Association for the
Advancement of Cost Engineering (AACE). This cost estimate is characterized by limited project definition,
widescale use of parametric models to calculate estimated costs (i.e., making extensive use of order-of-
magnitude costs from similar projects or proposals), and uncertainty. The estimated accuracy range for
the opinions of probable cost developed as part of this analysis is -30% to +50%. All estimated
construction costs are presented in 2020 U.S. dollars and include costs for engineering and project
administration. Further details of the planning-level opinions of probable cost are included in the memo
detailing the previous effort (reference (3)).
Estimated construction costs were compared to the total annualized benefit of each flood mitigation
option, divided over an assumed 60-year period (valuable life of the project). Benefit/cost (B/C) ratios
greater than one (1) indicate the estimated reduction in flood damage expected from a given mitigation
option is greater than the cost to implement that mitigation option. B/C ratios are presented in Table 6.
To: Jessica Wilson and Ross Bintner, City of Edina From: Cory Anderson, Greg Williams, and Sarah Stratton Subject: Infrastructure Options to Reduce Flood Risk in the Morningside Neighborhood Date: February 3, 2021 Page: 16
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Table 6 Economic assessment of the flood risk reduction options
Condition Annualized Damage, $ Annualized Benefit, $ Improvement Cost, $
Annual Improvement Cost, $ Benefit – Cost Benefit / Cost Ratio
Existing $362,600 --- --- --- --- ---
“Big” $260,400 $102,200 $5.5M $92,000 $10,200 1.1
“Bigger” $190,100 $172,500 $11.2M $187,000 -$14,500 0.9
“Biggest” $181,800 $180,800 $15.8M $263,000 -$82,200 0.7
The “Big” option of limited additional storage and conveyance capacity is the only option with a B/C ratio
greater than 1. However, this refined option reduces flood risk to the fewest number of homes and has
limited potential for adding future flood risk reduction efforts. The “Biggest” option has the lowest B/C
ratio at 0.7. Additionally, the “Biggest” option reduces risk for a number of homes that is similar to the
“Bigger” option, which costs nearly $5M less to design and construct. Regardless of the resulting B/C
ratios, the ETE discussions with additional local engineering experts confirmed that the refined options
use the most cost-effective approaches applicable in this area. The design phase of any selected flood risk
reduction option will also provide further opportunity to evaluate expanding benefits and reducing cost.
Additional discussion on the costs and benefits of several of the components is also provided in Section
5.0.
5.0 Tradeoffs and Opportunities
To provide a significant flood risk reduction benefit in the Morningside neighborhood, large infrastructure
changes are required. With some of those large infrastructure changes come similarly large changes to
the landscape. Because the neighborhood is mostly developed and open space is limited, the remaining
open space is highly valued by the community. However, as described herein, additional storage is a
necessary component to reduce flood risk, and storage underground and out of sight is not economically
feasible for this site. Therefore, there are some social, aesthetic, and recreational tradeoffs and
opportunities to consider as the City evaluates the feasibility of the refined options.
The swale through Weber Park (feature #2) will utilize park space and require moving or reconfiguring
some athletic fields.
• The benefits or opportunities are that the swale collects and concentrates runoff from the park
(versus diffusive flow in the existing condition), has high conveyance capacity as an open channel
feature, and could have water quality and infiltration benefits. If properly designed, the swale
could be an attractive feature that also provides clean-water benefits.
To: Jessica Wilson and Ross Bintner, City of Edina From: Cory Anderson, Greg Williams, and Sarah Stratton Subject: Infrastructure Options to Reduce Flood Risk in the Morningside Neighborhood Date: February 3, 2021 Page: 17
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• If the loss of the space in Weber Park is not acceptable, an alternative means of conveyance is
needed. It may be possible to further increase the pipe capacity (increase pipe size) under W 42nd
Street (feature #9) to Weber Pond. This will need more study in the design phase to confirm
constructability with related utility conflicts. The box culvert outlet (feature #3) from the open
space between Lynn Avenue and Kipling Avenue would be eliminated and the new outlet from
the southeast corner of the inundation area would become much larger. With this tradeoff, the
potential for water quality and infiltration benefits is lost, and stormwater is kept underground
and hidden, removing the potential for a water feature in Weber Park.
The expansion of Weber Pond into the woods to the north modifies that open space from its current use.
• The benefits or opportunities are that the expanded pond provides the storage required to
maximize neighborhood flood risk reduction at a much lower cost than underground storage. The
expanded pond could also provide passive recreation benefit through improvement of trails and
enhancement of the natural resource habitat. The design phase should employ landscape
architectural design to refine and promote a well-utilized recreational space if the open water
feature is maintained; this may include boardwalks, viewing alcoves, or other community features.
• If the loss of some of the woods to the north of Weber Pond is not acceptable, an alternative
means of storage is needed. If the woods are more valuable to the community than the sports
fields, then it may be preferable to leave the woods intact and expand Weber Pond into the
sports fields area (i.e., making feature #11 actual pond space and removing the sports fields).
The anticipated use of predictive pumping significantly increases the effective storage available within the
neighborhood, but introduces some uncertainty related to feasibility and operations.
• The benefits or opportunities of predictive pumping include a significant increase in available
storage achieved with a relatively small increase in cost. Increased storage is a foundational
component of the refined options, and predictive pumping allows more effective storage to be
achieved with a smaller footprint and, therefore, less impact to existing natural areas and open
space.
• Predictive pumping has operational risks that may affect performance (e.g., pump failure, difficulty
in predicting large precipitation events, downstream water levels that limit pumping). Uncertainty
related to predictive pumping is evaluated in greater detail in Section 3.1 of reference (5). These
risks may be mitigated by the development of an operating plan. Additional uncertainty in
feasibility (e.g., permitting requirements) must also be considered during optimization of any
refined options including predictive pumping (see Section 6.0).
Additional storage will be required to realize similar benefits without predictive pumping. Storage
options may include Weber Park athletic fields, private property, and/or Minikhada Vista Park in
St. Louis Park. Private property and St. Louis Park property each come with additional cost and
To: Jessica Wilson and Ross Bintner, City of Edina From: Cory Anderson, Greg Williams, and Sarah Stratton Subject: Infrastructure Options to Reduce Flood Risk in the Morningside Neighborhood Date: February 3, 2021 Page: 18
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tradeoffs that are uncertain because they are not under the City’s direct control. Several of these
options were removed from consideration due to cost, complexity, and other factors (e.g., being
outside City jurisdiction). The “Big” option provides a measure of the benefits achieved without
the predictive pumping.
Modifications to the storm sewer present an opportunity to alter the large conveyance pipe underneath
Crocker Avenue and W 42nd Street.
• The benefits or opportunities of modifying the storm sewer at Crocker Avenue and W 42nd Street
include the potential to add connections to alleviate backyard flooding issues. The flood risk in
these types of areas is primarily due to winter melt, which allows residents the ability to anticipate
issues and prepare temporary pumping or other mitigation (due to the relatively slow nature of
winter melt).
• Tradeoffs to this possible action include the need for land acquisition and/or easements for
access and structures. Additionally, connection of landlocked areas will transfer flood risk to
downstream areas where it may pose greater risk to structures and will require additional storage.
This opportunity was removed from consideration at this point in time due to concerns about
feasibility and the City’s preference to avoid acquisitions. It is worth noting however that the
refined options currently provide more benefit in the “downstream” portions of the neighborhood
where there are large storage features (see Figures B-7, C-7, and D-7 in Appendices B, C, and D,
respectively) so that in the future, additional stormwater connections can be made, thereby
increasing benefits throughout the neighborhood.
6.0 Conclusions
The Morningside neighborhood has a high potential for flood damage. Detailed flood-related studies
have been completed in the past few years in advance of expected street reconstruction in 2022 and 2023.
These studies have continually and transparently refined flood risk reduction options, considering the
economics, the benefits, and the values of the community, using direct engagement with the Flood Risk
Reduction Task Force for the earlier effort (July 2019 through February 2020), and a specific engagement
plan as part of this effort. Given the space available in the neighborhood, the values of the community,
and the funding that is expected to be available, refined options to reduce flood risk in an optimized way
have been summarized and presented in this memo.
The “Big” option of limited additional storage and conveyance capacity is the only option with a benefit-
to-cost (B/C) ratio greater than 1. However, this refined option reduces flood risk to the fewest number of
homes with limited potential for coordination with future flood risk reduction efforts. The “Bigger” option
is the minimum required to extend the benefit neighborhood wide. The “Biggest” option has the lowest
B/C ratio at 0.7. Additionally, the “Biggest” option reduces risk for a number of homes that is similar to the
“Bigger” option, which costs nearly $5M less to design and construct
To: Jessica Wilson and Ross Bintner, City of Edina From: Cory Anderson, Greg Williams, and Sarah Stratton Subject: Infrastructure Options to Reduce Flood Risk in the Morningside Neighborhood Date: February 3, 2021 Page: 19
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Upon approval to continue pursuing final design of a flood risk reduction project in the Morningside
neighborhood, the chosen refined option should be optimized once more in final design to match the
overall cost with the approved funding. This effort will coincide with additional evaluation of predictive
pumping feasibility and permitting, including coordination with the Minnesota Department of Natural
Resources (MDNR), Minnehaha Creek Watershed District (MCWD), and the City of Minneapolis. The final
design should consider detailed topographic survey data, wetland permitting, potential flood insurance
impacts, groundwater levels, and soils information from boreholes. The final design should also reconsider
the tradeoffs and opportunities and be reassessed for geographical balance that addresses risk reduction
and benefits, as discussed in Section 5.0. After optimizing the option to match funding and account for
tradeoffs and opportunities, the option should also be reassessed to finalize the estimate of flood damage
reduction benefits.
7.0 References
1. City of Edina. 2018 Comprehensive Water Resources Management Plan. Edina, MN : s.n., July 2018.
2. —. 2020 Street Reconstruction Projects. City of Edina. [Online]
https://www.bettertogetheredina.org/2020StreetRecon.
3. Barr Engineering Co. Morningside Neighborhood Flood Risk Reduction Strategy Conceptual Study.
November, 2018.
4. —. Morningside XP-SWMM Modeling. April, 2020.
5. —. Morningside Neighborhood Flood Infrastructure Project. October, 2020.
6. City of Edina. Flood Risk Reduction Strategy. s.l. : City of Edina Engineering Department, 2020.
7. —. City Service Status: Flooding and Drainage. City of Edina. [Online]
8. —. Flooding and Drainage. City of Edina. [Online] August 2020.
https://www.edinamn.gov/371/Flooding-and-Drainage.
9. —. Better Together. Morningside Flood Infrastructure Project. [Online] August 2020.
https://www.bettertogetheredina.org/6145/widgets/19058/documents/11586.
10. —. Edina Morningside Neighborhood Flood Risk Reduction Concepts. Edina, MN : s.n., September 2018.
11. FEMA. Estimated Flood Loss Potential. Flood Loss Estimations 2017. [Online] [Cited: September 1,
2018.] https://www.fema.gov/media-library-data/1499290622913-
0bcd74f47bf20aa94998a5a920837710/Flood_Loss_Estimations_2017.pdf.
Attachment A
Existing Conditions
Inundation Maps and Structure Impacts
Kojetin Park
Open Space 5
OpenSpace 6
WeberField Park
Weber Woods
LynnFrance40th
42nd
Morningside
44th
Sunnyside
Littel
SidellGrimesNatchezOakdale
Cur
ve Eaton45th InglewoodBranson CrockerAldenScottKiplingMontereyBarr Footer: ArcGIS 10.7.1, 2020-09-15 19:30 File: I:\Client\Edina\Projects\Morningside FRRS 23271798\Maps\Fig A-1 Existing Conditions 20% AEP.mxd User: EMA
20% ACE INUNDATION AND TOTAL FLOOD RISK
EXISTING CONDITIONSFIGURE A-1
Imagery: Hennepin County, 2018
Inundation Depth (feet)
< 0.1 feet
0.1 - 1 feet
1 - 3 feet
3 - 6 feet
6 - 9 feet
9 - 12 feet
> 12 feet
Total Flood Risk (160 Homes at Risk)
2
3
4
No Risk1 - Lowest Risk
5 - Highest Risk
!;N
0 175 350
Feet
Note: Total Flood Risk accountsfor all storm events modeled, notthe risk for an individual storm.
Kojetin Park
Open Space 5
OpenSpace 6
WeberField Park
Weber Woods
LynnFrance40th
42nd
Morningside
44th
Sunnyside
Littel
SidellGrimesNatchezOakdale
Cur
ve Eaton45th InglewoodBranson CrockerAldenScottKiplingMontereyBarr Footer: ArcGIS 10.7.1, 2020-09-15 19:33 File: I:\Client\Edina\Projects\Morningside FRRS 23271798\Maps\Fig A-2 Existing Conditions 10% AEP.mxd User: EMA
10% ACE INUNDATION AND TOTAL FLOOD RISK
EXISTING CONDITIONSFIGURE A-2
Imagery: Hennepin County, 2018
Inundation Depth (feet)
< 0.1 feet
0.1 - 1 feet
1 - 3 feet
3 - 6 feet
6 - 9 feet
9 - 12 feet
> 12 feet
Total Flood Risk (160 Homes at Risk)
2
3
4
No Risk1 - Lowest Risk
5 - Highest Risk
!;N
0 175 350
Feet
Note: Total Flood Risk accountsfor all storm events modeled, notthe risk for an individual storm.
Kojetin Park
Open Space 5
OpenSpace 6
WeberField Park
Weber Woods
LynnFrance40th
42nd
Morningside
44th
Sunnyside
Littel
SidellGrimesNatchezOakdale
Cur
ve Eaton45th InglewoodBranson CrockerAldenScottKiplingMontereyBarr Footer: ArcGIS 10.7.1, 2020-09-15 19:33 File: I:\Client\Edina\Projects\Morningside FRRS 23271798\Maps\Fig A-3 Existing Conditions 4% AEP.mxd User: EMA
4% ACE INUNDATION AND TOTAL FLOOD RISK
EXISTING CONDITIONSFIGURE A-3
Imagery: Hennepin County, 2018
Inundation Depth (feet)
< 0.1 feet
0.1 - 1 feet
1 - 3 feet
3 - 6 feet
6 - 9 feet
9 - 12 feet
> 12 feet
Total Flood Risk (160 Homes at Risk)
2
3
4
No Risk1 - Lowest Risk
5 - Highest Risk
!;N
0 175 350
Feet
Note: Total Flood Risk accountsfor all storm events modeled, notthe risk for an individual storm.
Kojetin Park
Open Space 5
OpenSpace 6
WeberField Park
Weber Woods
LynnFrance40th
42nd
Morningside
44th
Sunnyside
Littel
SidellGrimesNatchezOakdale
Cur
ve Eaton45th InglewoodBranson CrockerAldenScottKiplingMontereyBarr Footer: ArcGIS 10.7.1, 2020-09-15 19:33 File: I:\Client\Edina\Projects\Morningside FRRS 23271798\Maps\Fig A-4 Existing Conditions 2% AEP.mxd User: EMA
2% ACE INUNDATION AND TOTAL FLOOD RISK
EXISTING CONDITIONSFIGURE A-4
Inundation Depth (feet)
< 0.1 feet
0.1 - 1 feet
1 - 3 feet
3 - 6 feet
6 - 9 feet
9 - 12 feet
> 12 feet
Total Flood Risk (160 Homes at Risk)
2
3
4
No Risk1 - Lowest Risk
5 - Highest Risk
!;N
0 175 350
Feet
Note: Total Flood Risk accountsfor all storm events modeled, notthe risk for an individual storm.
Kojetin Park
Open Space 5
OpenSpace 6
WeberField Park
Weber Woods
LynnFrance40th
42nd
Morningside
44th
Sunnyside
Littel
SidellGrimesNatchezOakdale
Cur
ve Eaton45th InglewoodBranson CrockerAldenScottKiplingMontereyBarr Footer: ArcGIS 10.7.1, 2020-09-16 07:58 File: I:\Client\Edina\Projects\Morningside FRRS 23271798\Maps\Fig A-5 Existing Conditions 1% AEP.mxd User: EMA
1% ACE INUNDATION AND TOTAL FLOOD RISK
EXISTING CONDITIONSFIGURE A-5
!;N
Inundation Depth (feet)
< 0.1 feet
0.1 - 1 feet
1 - 3 feet
3 - 6 feet
6 - 9 feet
9 - 12 feet
> 12 feet
0 175 350
Feet
Total Flood Risk (160 Homes at Risk)
2
3
4
No Risk1 - Lowest Risk
5 - Highest Risk
Note: Total Flood Risk accountsfor all storm events modeled, notthe risk for an individual storm.
Kojetin Park
Open Space 5
OpenSpace 6
WeberField Park
Weber Woods
LynnFrance40th
42nd
Morningside
44th
Sunnyside
Littel
SidellGrimesNatchezOakdale
Cur
ve Eaton45th InglewoodBranson CrockerAldenScottKiplingMontereyBarr Footer: ArcGIS 10.7.1, 2020-09-15 19:33 File: I:\Client\Edina\Projects\Morningside FRRS 23271798\Maps\Fig A-6 Existing Conditions 0.2% AEP.mxd User: EMA
0.2% ACE INUNDATION AND TOTAL FLOOD RISK
EXISTING CONDITIONSFIGURE A-6
Imagery: Hennepin County, 2018
Inundation Depth (feet)
< 0.1 feet
0.1 - 1 feet
1 - 3 feet
3 - 6 feet
6 - 9 feet
9 - 12 feet
> 12 feet
Total Flood Risk (160 Homes at Risk)
2
3
4
No Risk1 - Lowest Risk
5 - Highest Risk
!;N
0 175 350
Feet
Note: Total Flood Risk accountsfor all storm events modeled, notthe risk for an individual storm.
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Attachment B
Refined Option at the ~$15M Cost
Inundation Maps and Structure Impacts
Kojetin Park
Open Space 5
OpenSpace 6
WeberField Park
Weber Woods
LynnFrance40th
42nd
Morningside
44th
Sunnyside
Littel
SidellGrimesNatchezOakdale
Cur
ve Eaton45th InglewoodBranson CrockerAldenScottKiplingMontereyBarr Footer: ArcGIS 10.7.1, 2020-09-15 20:05 File: I:\Client\Edina\Projects\Morningside FRRS 23271798\Maps\Fig F-1 Option 10 20% AEP.mxd User: EMA
20% ACE INUNDATION AND TOTAL FLOOD RISK REFINED COMBINATION OPTION, ~$15M COST
FIGURE B-1
Imagery: Hennepin County, 2018
Inundation Depth (feet)
< 0.1 feet
0.1 - 1 feet
1 - 3 feet
3 - 6 feet
6 - 9 feet
9 - 12 feet
> 12 feet
2
3
4
1 - Lowest Risk
5 - Highest Risk No Risk
Added Risk (0 home)
Homes Removed from
Risk (27 homes)
!;N
0 175 350
Feet
Note: Total Flood Risk accountsfor all storm events modeled, notthe risk for an individual storm.
Total Flood Risk (133 Homes at Risk)
Kojetin Park
Open Space 5
OpenSpace 6
WeberField Park
Weber Woods
LynnFrance40th
42nd
Morningside
44th
Sunnyside
Littel
SidellGrimesNatchezOakdale
Cur
ve Eaton45th InglewoodBranson CrockerAldenScottKiplingMontereyBarr Footer: ArcGIS 10.7.1, 2020-09-15 20:05 File: I:\Client\Edina\Projects\Morningside FRRS 23271798\Maps\Fig F-1 Option 10 20% AEP.mxd User: EMA
10% ACE INUNDATION AND TOTAL FLOOD RISK REFINED COMBINATION OPTION, ~$15M COST
FIGURE B-2
Imagery: Hennepin County, 2018
Inundation Depth (feet)
< 0.1 feet
0.1 - 1 feet
1 - 3 feet
3 - 6 feet
6 - 9 feet
9 - 12 feet
> 12 feet
2
3
4
1 - Lowest Risk
5 - Highest Risk No Risk
Added Risk (0 home)
Homes Removed from
Risk (27 homes)
!;N
0 175 350
Feet
Note: Total Flood Risk accountsfor all storm events modeled, notthe risk for an individual storm.
Total Flood Risk (133 Homes at Risk)
Kojetin Park
Open Space 5
OpenSpace 6
WeberField Park
Weber Woods
LynnFrance40th
42nd
Morningside
44th
Sunnyside
Littel
SidellGrimesNatchezOakdale
Cur
ve Eaton45th InglewoodBranson CrockerAldenScottKiplingMontereyBarr Footer: ArcGIS 10.7.1, 2020-09-15 20:05 File: I:\Client\Edina\Projects\Morningside FRRS 23271798\Maps\Fig F-1 Option 10 20% AEP.mxd User: EMA
4% ACE INUNDATION AND TOTAL FLOOD RISK REFINED COMBINATION OPTION, ~$15M COST
FIGURE B-3
Imagery: Hennepin County, 2018
Inundation Depth (feet)
< 0.1 feet
0.1 - 1 feet
1 - 3 feet
3 - 6 feet
6 - 9 feet
9 - 12 feet
> 12 feet
2
3
4
1 - Lowest Risk
5 - Highest Risk No Risk
Added Risk (0 home)
Homes Removed from
Risk (27 homes)
!;N
0 175 350
Feet
Note: Total Flood Risk accountsfor all storm events modeled, notthe risk for an individual storm.
Total Flood Risk (133 Homes at Risk)
Kojetin Park
Open Space 5
OpenSpace 6
WeberField Park
Weber Woods
LynnFrance40th
42nd
Morningside
44th
Sunnyside
Littel
SidellGrimesNatchezOakdale
Cur
ve Eaton45th InglewoodBranson CrockerAldenScottKiplingMontereyBarr Footer: ArcGIS 10.7.1, 2020-09-15 20:05 File: I:\Client\Edina\Projects\Morningside FRRS 23271798\Maps\Fig F-1 Option 10 20% AEP.mxd User: EMA
2% ACE INUNDATION AND TOTAL FLOOD RISK REFINED COMBINATION OPTION, ~$15M COST
FIGURE B-4
Imagery: Hennepin County, 2018
Inundation Depth (feet)
< 0.1 feet
0.1 - 1 feet
1 - 3 feet
3 - 6 feet
6 - 9 feet
9 - 12 feet
> 12 feet
2
3
4
1 - Lowest Risk
5 - Highest Risk No Risk
Added Risk (0 home)
Homes Removed from
Risk (27 homes)
!;N
0 175 350
Feet
Note: Total Flood Risk accountsfor all storm events modeled, notthe risk for an individual storm.
Total Flood Risk (133 Homes at Risk)
Kojetin Park
Open Space 5
OpenSpace 6
WeberField Park
Weber Woods
LynnFrance40th
42nd
Morningside
44th
Sunnyside
Littel
SidellGrimesNatchezOakdale
Cur
ve Eaton45th InglewoodBranson CrockerAldenScottKiplingMontereyBarr Footer: ArcGIS 10.7.1, 2020-09-15 20:05 File: I:\Client\Edina\Projects\Morningside FRRS 23271798\Maps\Fig F-1 Option 10 20% AEP.mxd User: EMA
1% ACE INUNDATION AND TOTAL FLOOD RISK REFINED COMBINATION OPTION, ~$15M COST
FIGURE B-5
Imagery: Hennepin County, 2018
Inundation Depth (feet)
< 0.1 feet
0.1 - 1 feet
1 - 3 feet
3 - 6 feet
6 - 9 feet
9 - 12 feet
> 12 feet
2
3
4
1 - Lowest Risk
5 - Highest Risk No Risk
Added Risk (0 home)
Homes Removed from
Risk (27 homes)
!;N
0 175 350
Feet
Note: Total Flood Risk accountsfor all storm events modeled, notthe risk for an individual storm.
Total Flood Risk (133 Homes at Risk)
Kojetin Park
Open Space 5
OpenSpace 6
WeberField Park
Weber Woods
LynnFrance40th
42nd
Morningside
44th
Sunnyside
Littel
SidellGrimesNatchezOakdale
Cur
ve Eaton45th InglewoodBranson CrockerAldenScottKiplingMontereyBarr Footer: ArcGIS 10.7.1, 2020-09-15 20:05 File: I:\Client\Edina\Projects\Morningside FRRS 23271798\Maps\Fig F-1 Option 10 20% AEP.mxd User: EMA
0.2% ACE INUNDATION AND TOTAL FLOOD RISK REFINED COMBINATION OPTION, ~$15M COST
FIGURE B-6
Imagery: Hennepin County, 2018
Inundation Depth (feet)
< 0.1 feet
0.1 - 1 feet
1 - 3 feet
3 - 6 feet
6 - 9 feet
9 - 12 feet
> 12 feet
2
3
4
1 - Lowest Risk
5 - Highest Risk No Risk
Added Risk (0 home)
Homes Removed from
Risk (27 homes)
!;N
0 175 350
Feet
Note: Total Flood Risk accountsfor all storm events modeled, notthe risk for an individual storm.
Total Flood Risk (133 Homes at Risk)
$15,600; 64%$51,700; 98%
$20,100; 40%
$1,600; 6%
$500; 4%
$63,200; 79%
$3,400; 14%$17,400; 25%$7,200; 28%
Sources: Esri, HERE, Garmin, USGS, Intermap, INCREMENT P, NRCan, Esri Japan, METI, Esri China(Hong Kong), Esri Korea, Esri (Thailand), NGCC, (c) OpenStreetMap contributors, and the GIS UserCommunity
Barr Footer: ArcGIS 10.7.1, 2021-01-18 16:20 File: I:\Client\Edina\Projects\Morningside FRRS 23271798\Maps\Fig B-7 Option 12 Zone Benefits.mxd User: EMA
FIGURE B-7
0 175 350
Feet
Primary Structures Annualized Damage Reduction, $
< $10,000
$10,000 - $20,000
$20,000 - $30,000
$30,000 - $40,000
$40,000 - $50,000
$50,000 - $60,000
$60,000 - $70,000
TOTAL FLOOD RISKREDUCTION AS ADOLLAR AMOUNT ANDAS A PERCENTAGE
REFINED COMBINATIONOPTION, ~$15M COST
P:\Mpls\23 MN\27\23271798 Morningside FRR Prelim Eng & E\WorkFiles\Mitigation Alternatives Technical Memo\Feb2021
Memo\Morningside_Flood_Infrastructure_Technical_Memo_02032021.docx
Attachment C
Refined Option at the ~$10M Cost
Inundation Maps and Structure Impacts
Kojetin Park
Open Space 5
OpenSpace 6
WeberField Park
Weber Woods
LynnFrance40th
42nd
Morningside
44th
Sunnyside
Littel
SidellGrimesNatchezOakdale
Cur
ve Eaton45th InglewoodBranson CrockerAldenScottKiplingMontereyBarr Footer: ArcGIS 10.7.1, 2020-09-15 20:05 File: I:\Client\Edina\Projects\Morningside FRRS 23271798\Maps\Fig F-1 Option 10 20% AEP.mxd User: EMA
20% ACE INUNDATION AND TOTAL FLOOD RISK REFINED COMBINATION OPTION, ~$10M COST
FIGURE C-1
Imagery: Hennepin County, 2018
Inundation Depth (feet)
< 0.1 feet
0.1 - 1 feet
1 - 3 feet
3 - 6 feet
6 - 9 feet
9 - 12 feet
> 12 feet
2
3
4
1 - Lowest Risk
5 - Highest Risk No Risk
Added Risk (0 home)
Homes Removed from
Risk (19 homes)
!;N
0 175 350
Feet
Note: Total Flood Risk accountsfor all storm events modeled, notthe risk for an individual storm.
Total Flood Risk (141 Homes at Risk)
Kojetin Park
Open Space 5
OpenSpace 6
WeberField Park
Weber Woods
LynnFrance40th
42nd
Morningside
44th
Sunnyside
Littel
SidellGrimesNatchezOakdale
Cur
ve Eaton45th InglewoodBranson CrockerAldenScottKiplingMontereyBarr Footer: ArcGIS 10.7.1, 2020-09-15 20:05 File: I:\Client\Edina\Projects\Morningside FRRS 23271798\Maps\Fig F-1 Option 10 20% AEP.mxd User: EMA
10% ACE INUNDATION AND TOTAL FLOOD RISK REFINED COMBINATION OPTION, ~$10M COST
FIGURE C-2
Imagery: Hennepin County, 2018
Inundation Depth (feet)
< 0.1 feet
0.1 - 1 feet
1 - 3 feet
3 - 6 feet
6 - 9 feet
9 - 12 feet
> 12 feet
2
3
4
1 - Lowest Risk
5 - Highest Risk No Risk
Added Risk (0 home)
Homes Removed from
Risk (19 homes)
!;N
0 175 350
Feet
Note: Total Flood Risk accountsfor all storm events modeled, notthe risk for an individual storm.
Total Flood Risk (141 Homes at Risk)
Kojetin Park
Open Space 5
OpenSpace 6
WeberField Park
Weber Woods
LynnFrance40th
42nd
Morningside
44th
Sunnyside
Littel
SidellGrimesNatchezOakdale
Cur
ve Eaton45th InglewoodBranson CrockerAldenScottKiplingMontereyBarr Footer: ArcGIS 10.7.1, 2020-09-15 20:05 File: I:\Client\Edina\Projects\Morningside FRRS 23271798\Maps\Fig F-1 Option 10 20% AEP.mxd User: EMA
4% ACE INUNDATION AND TOTAL FLOOD RISK REFINED COMBINATION OPTION, ~$10M COST
FIGURE C-3
Imagery: Hennepin County, 2018
Inundation Depth (feet)
< 0.1 feet
0.1 - 1 feet
1 - 3 feet
3 - 6 feet
6 - 9 feet
9 - 12 feet
> 12 feet
2
3
4
1 - Lowest Risk
5 - Highest Risk No Risk
Added Risk (0 home)
Homes Removed from
Risk (19 homes)
!;N
0 175 350
Feet
Note: Total Flood Risk accountsfor all storm events modeled, notthe risk for an individual storm.
Total Flood Risk (141 Homes at Risk)
Kojetin Park
Open Space 5
OpenSpace 6
WeberField Park
Weber Woods
LynnFrance40th
42nd
Morningside
44th
Sunnyside
Littel
SidellGrimesNatchezOakdale
Cur
ve Eaton45th InglewoodBranson CrockerAldenScottKiplingMontereyBarr Footer: ArcGIS 10.7.1, 2020-09-15 20:05 File: I:\Client\Edina\Projects\Morningside FRRS 23271798\Maps\Fig F-1 Option 10 20% AEP.mxd User: EMA
2% ACE INUNDATION AND TOTAL FLOOD RISK REFINED COMBINATION OPTION, ~$10M COST
FIGURE C-4
Imagery: Hennepin County, 2018
Inundation Depth (feet)
< 0.1 feet
0.1 - 1 feet
1 - 3 feet
3 - 6 feet
6 - 9 feet
9 - 12 feet
> 12 feet
2
3
4
1 - Lowest Risk
5 - Highest Risk No Risk
Added Risk (0 home)
Homes Removed from
Risk (19 homes)
!;N
0 175 350
Feet
Note: Total Flood Risk accountsfor all storm events modeled, notthe risk for an individual storm.
Total Flood Risk (141 Homes at Risk)
Kojetin Park
Open Space 5
OpenSpace 6
WeberField Park
Weber Woods
LynnFrance40th
42nd
Morningside
44th
Sunnyside
Littel
SidellGrimesNatchezOakdale
Cur
ve Eaton45th InglewoodBranson CrockerAldenScottKiplingMontereyBarr Footer: ArcGIS 10.7.1, 2020-09-15 20:05 File: I:\Client\Edina\Projects\Morningside FRRS 23271798\Maps\Fig F-1 Option 10 20% AEP.mxd User: EMA
1% ACE INUNDATION AND TOTAL FLOOD RISK REFINED COMBINATION OPTION, ~$10M COST
FIGURE C-5
Imagery: Hennepin County, 2018
Inundation Depth (feet)
< 0.1 feet
0.1 - 1 feet
1 - 3 feet
3 - 6 feet
6 - 9 feet
9 - 12 feet
> 12 feet
2
3
4
1 - Lowest Risk
5 - Highest Risk No Risk
Added Risk (0 home)
Homes Removed from
Risk (19 homes)
!;N
0 175 350
Feet
Note: Total Flood Risk accountsfor all storm events modeled, notthe risk for an individual storm.
Total Flood Risk (141 Homes at Risk)
Kojetin Park
Open Space 5
OpenSpace 6
WeberField Park
Weber Woods
LynnFrance40th
42nd
Morningside
44th
Sunnyside
Littel
SidellGrimesNatchezOakdale
Cur
ve Eaton45th InglewoodBranson CrockerAldenScottKiplingMontereyBarr Footer: ArcGIS 10.7.1, 2020-09-15 20:05 File: I:\Client\Edina\Projects\Morningside FRRS 23271798\Maps\Fig F-1 Option 10 20% AEP.mxd User: EMA
0.2% ACE INUNDATION AND TOTAL FLOOD RISK REFINED COMBINATION OPTION, ~$10M COST
FIGURE C-6
Imagery: Hennepin County, 2018
Inundation Depth (feet)
< 0.1 feet
0.1 - 1 feet
1 - 3 feet
3 - 6 feet
6 - 9 feet
9 - 12 feet
> 12 feet
2
3
4
1 - Lowest Risk
5 - Highest Risk No Risk
Added Risk (0 home)
Homes Removed from
Risk (19 homes)
!;N
0 175 350
Feet
Note: Total Flood Risk accountsfor all storm events modeled, notthe risk for an individual storm.
Total Flood Risk (141 Homes at Risk)
$13,100; 54%$48,900; 93%
$17,800; 35%
$1,600; 6%
$500; 4%
$63,000; 79%
$3,400; 14%$16,900; 24%$7,200; 28%
Sources: Esri, HERE, Garmin, USGS, Intermap, INCREMENT P, NRCan, Esri Japan, METI, Esri China(Hong Kong), Esri Korea, Esri (Thailand), NGCC, (c) OpenStreetMap contributors, and the GIS UserCommunity
Barr Footer: ArcGIS 10.7.1, 2021-01-18 16:15 File: I:\Client\Edina\Projects\Morningside FRRS 23271798\Maps\Fig C-7 Option 12 Zone Benefits.mxd User: EMA
FIGURE C-7
0 175 350
Feet
Primary Structures Annualized Damage Reduction, $
< $10,000
$10,000 - $20,000
$20,000 - $30,000
$30,000 - $40,000
$40,000 - $50,000
$50,000 - $60,000
$60,000 - $70,000
TOTAL FLOOD RISKREDUCTION AS ADOLLAR AMOUNT ANDAS A PERCENTAGE
REFINED COMBINATIONOPTION, ~$10M COST
P:\Mpls\23 MN\27\23271798 Morningside FRR Prelim Eng & E\WorkFiles\Mitigation Alternatives Technical Memo\Feb2021
Memo\Morningside_Flood_Infrastructure_Technical_Memo_02032021.docx
Attachment D
Refined Option at the ~$5M Cost
Inundation Maps and Structure Impacts
Kojetin Park
Open Space 5
OpenSpace 6
WeberField Park
Weber Woods
LynnFrance40th
42nd
Morningside
44th
Sunnyside
Littel
SidellGrimesNatchezOakdale
Cur
ve Eaton45th InglewoodBranson CrockerAldenScottKiplingMontereyBarr Footer: ArcGIS 10.7.1, 2020-09-15 20:05 File: I:\Client\Edina\Projects\Morningside FRRS 23271798\Maps\Fig F-1 Option 10 20% AEP.mxd User: EMA
20% ACE INUNDATION AND TOTAL FLOOD RISK REFINED COMBINATION OPTION, ~$5M COST
FIGURE D-1
Imagery: Hennepin County, 2018
Inundation Depth (feet)
< 0.1 feet
0.1 - 1 feet
1 - 3 feet
3 - 6 feet
6 - 9 feet
9 - 12 feet
> 12 feet
2
3
4
1 - Lowest Risk
5 - Highest Risk No Risk
Added Risk (0 home)
Homes Removed from
Risk (6 homes)
!;N
0 175 350
Feet
Note: Total Flood Risk accountsfor all storm events modeled, notthe risk for an individual storm.
Total Flood Risk (154 Homes at Risk)
Kojetin Park
Open Space 5
OpenSpace 6
WeberField Park
Weber Woods
LynnFrance40th
42nd
Morningside
44th
Sunnyside
Littel
SidellGrimesNatchezOakdale
Cur
ve Eaton45th InglewoodBranson CrockerAldenScottKiplingMontereyBarr Footer: ArcGIS 10.7.1, 2020-09-15 20:05 File: I:\Client\Edina\Projects\Morningside FRRS 23271798\Maps\Fig F-1 Option 10 20% AEP.mxd User: EMA
10% ACE INUNDATION AND TOTAL FLOOD RISK REFINED COMBINATION OPTION, ~$5M COST
FIGURE D-2
Imagery: Hennepin County, 2018
Inundation Depth (feet)
< 0.1 feet
0.1 - 1 feet
1 - 3 feet
3 - 6 feet
6 - 9 feet
9 - 12 feet
> 12 feet
2
3
4
1 - Lowest Risk
5 - Highest Risk No Risk
Added Risk (0 home)
Homes Removed from
Risk (6 homes)
!;N
0 175 350
Feet
Note: Total Flood Risk accountsfor all storm events modeled, notthe risk for an individual storm.
Total Flood Risk (154 Homes at Risk)
Kojetin Park
Open Space 5
OpenSpace 6
WeberField Park
Weber Woods
LynnFrance40th
42nd
Morningside
44th
Sunnyside
Littel
SidellGrimesNatchezOakdale
Cur
ve Eaton45th InglewoodBranson CrockerAldenScottKiplingMontereyBarr Footer: ArcGIS 10.7.1, 2020-09-15 20:05 File: I:\Client\Edina\Projects\Morningside FRRS 23271798\Maps\Fig F-1 Option 10 20% AEP.mxd User: EMA
4% ACE INUNDATION AND TOTAL FLOOD RISK REFINED COMBINATION OPTION, ~$5M COST
FIGURE D-3
Imagery: Hennepin County, 2018
Inundation Depth (feet)
< 0.1 feet
0.1 - 1 feet
1 - 3 feet
3 - 6 feet
6 - 9 feet
9 - 12 feet
> 12 feet
2
3
4
1 - Lowest Risk
5 - Highest Risk No Risk
Added Risk (0 home)
Homes Removed from
Risk (6 homes)
!;N
0 175 350
Feet
Note: Total Flood Risk accountsfor all storm events modeled, notthe risk for an individual storm.
Total Flood Risk (154 Homes at Risk)
Kojetin Park
Open Space 5
OpenSpace 6
WeberField Park
Weber Woods
LynnFrance40th
42nd
Morningside
44th
Sunnyside
Littel
SidellGrimesNatchezOakdale
Cur
ve Eaton45th InglewoodBranson CrockerAldenScottKiplingMontereyBarr Footer: ArcGIS 10.7.1, 2020-09-15 20:05 File: I:\Client\Edina\Projects\Morningside FRRS 23271798\Maps\Fig F-1 Option 10 20% AEP.mxd User: EMA
2% ACE INUNDATION AND TOTAL FLOOD RISK REFINED COMBINATION OPTION, ~$5M COST
FIGURE D-4
Imagery: Hennepin County, 2018
Inundation Depth (feet)
< 0.1 feet
0.1 - 1 feet
1 - 3 feet
3 - 6 feet
6 - 9 feet
9 - 12 feet
> 12 feet
2
3
4
1 - Lowest Risk
5 - Highest Risk No Risk
Added Risk (0 home)
Homes Removed from
Risk (6 homes)
!;N
0 175 350
Feet
Note: Total Flood Risk accountsfor all storm events modeled, notthe risk for an individual storm.
Total Flood Risk (154 Homes at Risk)
Kojetin Park
Open Space 5
OpenSpace 6
WeberField Park
Weber Woods
LynnFrance40th
42nd
Morningside
44th
Sunnyside
Littel
SidellGrimesNatchezOakdale
Cur
ve Eaton45th InglewoodBranson CrockerAldenScottKiplingMontereyBarr Footer: ArcGIS 10.7.1, 2020-09-15 20:05 File: I:\Client\Edina\Projects\Morningside FRRS 23271798\Maps\Fig F-1 Option 10 20% AEP.mxd User: EMA
1% ACE INUNDATION AND TOTAL FLOOD RISK REFINED COMBINATION OPTION, ~$5M COST
FIGURE D-5
Imagery: Hennepin County, 2018
Inundation Depth (feet)
< 0.1 feet
0.1 - 1 feet
1 - 3 feet
3 - 6 feet
6 - 9 feet
9 - 12 feet
> 12 feet
2
3
4
1 - Lowest Risk
5 - Highest Risk No Risk
Added Risk (0 home)
Homes Removed from
Risk (6 homes)
!;N
0 175 350
Feet
Note: Total Flood Risk accountsfor all storm events modeled, notthe risk for an individual storm.
Total Flood Risk (154 Homes at Risk)
Kojetin Park
Open Space 5
OpenSpace 6
WeberField Park
Weber Woods
LynnFrance40th
42nd
Morningside
44th
Sunnyside
Littel
SidellGrimesNatchezOakdale
Cur
ve Eaton45th InglewoodBranson CrockerAldenScottKiplingMontereyBarr Footer: ArcGIS 10.7.1, 2020-09-15 20:05 File: I:\Client\Edina\Projects\Morningside FRRS 23271798\Maps\Fig F-1 Option 10 20% AEP.mxd User: EMA
0.2% ACE INUNDATION AND TOTAL FLOOD RISK REFINED COMBINATION OPTION, ~$5M COST
FIGURE D-6
Imagery: Hennepin County, 2018
Inundation Depth (feet)
< 0.1 feet
0.1 - 1 feet
1 - 3 feet
3 - 6 feet
6 - 9 feet
9 - 12 feet
> 12 feet
2
3
4
1 - Lowest Risk
5 - Highest Risk No Risk
Added Risk (0 home)
Homes Removed from
Risk (6 homes)
!;N
0 175 350
Feet
Note: Total Flood Risk accountsfor all storm events modeled, notthe risk for an individual storm.
Total Flood Risk (154 Homes at Risk)
$13,300; 54%$18,600; 35%
$2,100; 4%
$0; 0%
$300; 2%
$53,700; 67%
$3,400; 14%$3,600; 5%$7,200; 28%
Sources: Esri, HERE, Garmin, USGS, Intermap, INCREMENT P, NRCan, Esri Japan, METI, Esri China(Hong Kong), Esri Korea, Esri (Thailand), NGCC, (c) OpenStreetMap contributors, and the GIS UserCommunity
Barr Footer: ArcGIS 10.7.1, 2021-01-18 16:24 File: I:\Client\Edina\Projects\Morningside FRRS 23271798\Maps\Fig D-7 Option 12 Zone Benefits.mxd User: EMA
TOTAL FLOOD RISKREDUCTION AS ADOLLAR AMOUNT ANDAS A PERCENTAGE
FIGURE D-7
0 175 350
Feet
Primary Structures Annualized Damage Reduction, $
< $10,000
$10,000 - $20,000
$20,000 - $30,000
$30,000 - $40,000
$40,000 - $50,000
$50,000 - $60,000
$60,000 - $70,000
REFINED COMBINATIONOPTION, ~$5M COST
P:\Mpls\23 MN\27\23271798 Morningside FRR Prelim Eng & E\WorkFiles\Mitigation Alternatives Technical Memo\Feb2021
Memo\Morningside_Flood_Infrastructure_Technical_Memo_02032021.docx
Attachment E
Planning Level Opinion of Probable Construction Costs
PREPARED BY: BARR ENGINEERING COMPANY SHEET:1 OF 5
BY:CDA DATE:8/27/2020
FEASIBILITY STUDY CHECKED BY:KJN2 DATE:12/3/2020
ENGINEER'S OPINION OF PROBABLE PROJECT COST APPROVED BY:DATE:
PROJECT:Morningside FRR Preliminary Engineering ISSUED:DATE:
LOCATION:City of Edina ISSUED:DATE:
PROJECT #:23/27-1798.00 ISSUED:DATE:
OPINION OF COST - SUMMARY ISSUED:DATE:
Engineer's Opinion of Probable Project Cost
Morningside Flood Mitigation Feasibility Project
REFINED COMBINATION OPTION at ~$15M
Cat.ESTIMATED
No.ITEM DESCRIPTION UNIT QUANTITY UNIT COST ITEM COST
General Mobilization/Demobilization (<10%)LS 1 $500,000.00 $500,000.00
Temporary Erosion Control LS 1 $70,000.00 $70,000.00
Flotation Silt Curtain LF 450 $11.00 $4,950.00
Excavate Excavation CY 69,000 $4.00 $276,000.00
Weber Pond Off Site Disposal of Excavated Material CY 69,000 $18.00 $1,242,000.00
Dewatering LS 1 $50,000.00 $50,000.00
Excavate Tree 2", B&B Each 150 $500.00 $75,000.00
Weber Woods Clearing and Grubbing AC 5 $8,500.00 $42,500.00
Excavation CY 89,000 $4.00 $356,000.00
Off Site Disposal of Excavated Material CY 89,000 $18.00 $1,602,000.00
Lower Sport Excavation CY 27,000 $4.00 $108,000.00
Fieds in Park Off Site Disposal of Excavated Material CY 27,000 $18.00 $486,000.00
Turf Establishment (w/ Disc Anchored Mulch)AC 1.2 $3,000.00 $3,636.09
Erosion Control Blanket SY 3,610 $3.00 $10,830.00
Remove and Rebuild 3 baseball diamonds LS 1 $300,000.00 $300,000.00
Excavation CY 15,000 $4.00 $60,000.00
Off Site Disposal of Excavated Material CY 15,000 $18.00 $270,000.00
Turf Establishment (w/ Disc Anchored Mulch)AC 1.4 $3,000.00 $4,338.84
Erosion Control Blanket SY 2,220 $3.00 $6,660.00
Remove and Rebuild ice hockey rink area LS 1 $50,000.00 $50,000.00
Swale Excavation CY 3,900 $4.00 $15,600.00
through Off Site Disposal of Excavated Material CY 3,900 $18.00 $70,200.00
Park Upland Native Vegetation AC 0.4 $5,000.00 $1,928.37
Erosion Control Blanket SY 1,870 $3.00 $5,610.00
Walking Trail LS 1 $7,000.00 $7,000.00
Avail Excavation CY 5,000 $4.00 $20,000.00
Academy Off Site Disposal of Excavated Material CY 5,000 $18.00 $90,000.00
Excavation Tree 2", B&B Each 25 $500.00 $12,500.00
Clearing and Grubbing AC 0.8 $8,500.00 $7,219.93
Upland Native Vegetation AC 0.8 $5,000.00 $4,247.02
24" RC Pipe Sewer (Furnish and Install) (12 - 13' depth)LF 400 $120.00 $48,000.00
Inglewood 36" RC Pipe Sewer (Furnish and Install) (8 - 13' depth)LF 1,000 $180.00 $180,000.00
Construct Drainage Structure SD-60 LF 30 $730.00 $21,900.00
Tie-In Storm Sewer Main to Manhole Each 2 $1,000.00 $2,000.00
Susan Excavation CY 20,000 $4.00 $80,000.00
Lindgren Off Site Disposal of Excavated Material CY 20,000 $18.00 $360,000.00
School Turf Establishment (w/ Disc Anchored Mulch)AC 2.5 $3,000.00 $7,575.76
Park Erosion Control Blanket SY 2,780 $3.00 $8,340.00
10' W x 4' H Box Culvert (Furnish and Install)LF 470 $650.00 $305,500.00
Open Space Excavation CY 29,000 $4.00 $116,000.00
Number 5 Off Site Disposal of Excavated Material CY 29,000 $18.00 $522,000.00
10' W x 4' H Box Culvert (Furnish and Install)LF 470 $650.00 $305,500.00
Dewatering LS 1 $50,000.00 $50,000.00
P:\Mpls\23 MN\27\23271798 Morningside FRR Prelim Eng & E\WorkFiles\Cost Benefit methods\Engineers Opinion of Probable Cost_20201203.xlsx 1
PREPARED BY: BARR ENGINEERING COMPANY SHEET:1 OF 5
BY:CDA DATE:8/27/2020
FEASIBILITY STUDY CHECKED BY:KJN2 DATE:12/3/2020
ENGINEER'S OPINION OF PROBABLE PROJECT COST APPROVED BY:DATE:
PROJECT:Morningside FRR Preliminary Engineering ISSUED:DATE:
LOCATION:City of Edina ISSUED:DATE:
PROJECT #:23/27-1798.00 ISSUED:DATE:
OPINION OF COST - SUMMARY ISSUED:DATE:
Engineer's Opinion of Probable Project Cost
Morningside Flood Mitigation Feasibility Project
REFINED COMBINATION OPTION at ~$15M
Cat.ESTIMATED
No.ITEM DESCRIPTION UNIT QUANTITY UNIT COST ITEM COST
New / Remove and Dispose of Existing Storm Sewer LF 4,580 $20.00 $91,600.00
Additional Remove and Dispose of Existing Manhole/Catch Basin Each 22 $850.00 $18,700.00
Pipe Capacity 24" RC Pipe Sewer (Furnish and Install) (12 - 13' depth)LF 728 $120.00 $87,360.00
36" RC Pipe Sewer (Furnish and Install) (8 - 13' depth)LF 710 $180.00 $127,800.00
48" RC Pipe Sewer (Furnish and Install) (15' depth)LF 368 $300.00 $110,400.00
60" RC Pipe Sewer (Furnish and Install) (8 - 10' depth)LF 840 $320.00 $268,800.00
60" RC Pipe Sewer (Furnish and Install) (10 - 16' depth)LF 2,630 $400.00 $1,052,000.00
Construct Drainage Structure SD-48 LF 434 $450.00 $195,300.00
Construct Drainage Structure SD-60 LF 56 $730.00 $40,880.00
Construct Drainage Structure SD-72 LF 14 $970.00 $13,580.00
Construct Drainage Structure SD-84 LF 224 $1,360.00 $304,640.00
Casting Assembly Each 52 $800.00 $41,600.00
Tie-In Storm Sewer Main to Manhole Each 9 $1,000.00 $9,000.00
Connect CB Leads to Constructed Storm Sewer Each 68 $700.00 $47,600.00
Pump System
Opti CMAC Predictive Pumping Control System (Furnish and
Install)Each 1 $85,000.00 $85,000.00
For Weber
Pond
4,000 GPM Pumping Station (Includes Building Structure, Electric
Supply, Control Panel)LS 1 $700,000.00 $700,000.00
Pumping Station Outlet Piping (Furnish and Install)LF 1,100 $40.00 $44,000.00
Pumping Station Inlet Suction Piping (Furnish and Install)LF 100 $40.00 $4,000.00
CONSTRUCTION SUBTOTAL $11,001,000.00
CONSTRUCTION CONTINGENCY (30%)$3,300,000.00
ESTIMATED CONSTRUCTION COST $14,301,000.00
ENGINEERING, DESIGN, PERMITTING, AND CONSTRUCTION
OBSERVATION (10%)$1,430,000.00
RESIDENTIAL/CONSTRUCTION PERMANENT EASEMENT $56,000.00
ESTIMATED TOTAL PROJECT COST $15,787,000.00
-30%$11,051,000.00
50%$23,681,000.00
Notes
6 Estimate costs are to design, construct, and permit each alternative. The estimated costs do not include maintenance, monitoring or additional tasks following
construction.
7 Furnish and Install pipe cost per lineal foot includes all trenching, bedding, backfilling, compaction, and disposal of excess materials
8 Estimate costs are reported to nearest thousand dollars.
ESTIMATED ACCURACY RANGE
1 Limited Design Work Completed
2 Quantities Based on Design Work Completed.
3 Unit Prices Based on Information Available at This Time.
4 Minimal Soil and Field Investigations Completed. Costs do not included remediation of contaminated soils (if found).
5 This feasibility-level (Class 4, 10-15% design completion per ASTM E 2516-06) cost estimate is based on feasibility-level designs, alignments, quantities and unit
prices. Costs will change with further design. Time value-of-money escalation costs are not included. A construction schedule is not available at this time.
Contingency is an allowance for the net sum of costs that will be in the Final Total Project Cost at the time of the completion of design, but are not included at
this level of project definition. The estimated accuracy range for the Total Project Cost as the project is defined is -30% to +50%. The accuracy range is based on
professional judgement considering the level of design completed, the complexity of the project and the uncertainties in the project as scoped. The contingency
and the accuracy range are not intended to include costs for future scope changes that are not part of the project as currently scoped or costs for risk
contingency. Operation and Maintenance costs are not included.
P:\Mpls\23 MN\27\23271798 Morningside FRR Prelim Eng & E\WorkFiles\Cost Benefit methods\Engineers Opinion of Probable Cost_20201203.xlsx 2
PREPARED BY: BARR ENGINEERING COMPANY SHEET:1 OF 5
BY:CDA DATE:8/27/2020
FEASIBILITY STUDY CHECKED BY:KJN2 DATE:12/3/2020
ENGINEER'S OPINION OF PROBABLE PROJECT COST APPROVED BY:DATE:
PROJECT:Morningside FRR Preliminary Engineering ISSUED:DATE:
LOCATION:City of Edina ISSUED:DATE:
PROJECT #:23/27-1798.00 ISSUED:DATE:
OPINION OF COST - SUMMARY ISSUED:DATE:
Engineer's Opinion of Probable Project Cost
Morningside Flood Mitigation Feasibility Project
REFINED COMBINATION OPTION at ~$10M
Cat.ESTIMATED
No.ITEM DESCRIPTION UNIT QUANTITY UNIT COST ITEM COST
General Mobilization/Demobilization (<10%)LS 1 $500,000.00 $500,000.00
Temporary Erosion Control LS 1 $50,000.00 $50,000.00
Flotation Silt Curtain LF 450 $11.00 $4,950.00
Excavate Excavation CY 49,000 $4.00 $196,000.00
Weber Pond Off Site Disposal of Excavated Material CY 49,000 $18.00 $882,000.00
Dewatering LS 1 $50,000.00 $50,000.00
Excavate Tree 2", B&B Each 150 $500.00 $75,000.00
Weber Woods Clearing and Grubbing AC 5 $8,500.00 $42,500.00
Excavation CY 76,000 $4.00 $304,000.00
Off Site Disposal of Excavated Material CY 76,000 $18.00 $1,368,000.00
Lower Sport Excavation CY $4.00 $0.00
Fieds in Park Off Site Disposal of Excavated Material CY $18.00 $0.00
Turf Establishment (w/ Disc Anchored Mulch)AC $3,000.00 $0.00
Erosion Control Blanket SY $3.00 $0.00
Remove and Rebuild 3 baseball diamonds LS $300,000.00 $0.00
Excavation CY $4.00 $0.00
Off Site Disposal of Excavated Material CY $18.00 $0.00
Turf Establishment (w/ Disc Anchored Mulch)AC $3,000.00 $0.00
Erosion Control Blanket SY $3.00 $0.00
Remove and Rebuild ice hockey rink area LS $50,000.00 $0.00
Swale Excavation CY 3,900 $4.00 $15,600.00
through Off Site Disposal of Excavated Material CY 3,900 $18.00 $70,200.00
Park Upland Native Vegetation AC 0.4 $5,000.00 $1,928.37
Erosion Control Blanket SY 1,870 $3.00 $5,610.00
Walking Trail LS 1 $7,000.00 $7,000.00
Avail Excavation CY $4.00 $0.00
Academy Off Site Disposal of Excavated Material CY $18.00 $0.00
Excavation Tree 2", B&B Each $500.00 $0.00
Clearing and Grubbing AC $8,500.00 $0.00
Upland Native Vegetation AC $5,000.00 $0.00
24" RC Pipe Sewer (Furnish and Install) (12 - 13' depth)LF $120.00 $0.00
Inglewood 36" RC Pipe Sewer (Furnish and Install) (8 - 13' depth)LF $180.00 $0.00
Construct Drainage Structure SD-60 LF $730.00 $0.00
Tie-In Storm Sewer Main to Manhole Each $1,000.00 $0.00
Susan Excavation CY $4.00 $0.00
Lindgren Off Site Disposal of Excavated Material CY $18.00 $0.00
School Turf Establishment (w/ Disc Anchored Mulch)AC $3,000.00 $0.00
Park Erosion Control Blanket SY $3.00 $0.00
10' W x 4' H Box Culvert (Furnish and Install)LF $650.00 $0.00
Open Space Excavation CY 29,000 $4.00 $116,000.00
Number 5 Off Site Disposal of Excavated Material CY 29,000 $18.00 $522,000.00
10' W x 4' H Box Culvert (Furnish and Install)LF 470 $650.00 $305,500.00
Dewatering LS 1 $50,000.00 $50,000.00
P:\Mpls\23 MN\27\23271798 Morningside FRR Prelim Eng & E\WorkFiles\Cost Benefit methods\Engineers Opinion of Probable Cost_20201203.xlsx 3
PREPARED BY: BARR ENGINEERING COMPANY SHEET:1 OF 5
BY:CDA DATE:8/27/2020
FEASIBILITY STUDY CHECKED BY:KJN2 DATE:12/3/2020
ENGINEER'S OPINION OF PROBABLE PROJECT COST APPROVED BY:DATE:
PROJECT:Morningside FRR Preliminary Engineering ISSUED:DATE:
LOCATION:City of Edina ISSUED:DATE:
PROJECT #:23/27-1798.00 ISSUED:DATE:
OPINION OF COST - SUMMARY ISSUED:DATE:
Engineer's Opinion of Probable Project Cost
Morningside Flood Mitigation Feasibility Project
REFINED COMBINATION OPTION at ~$10M
Cat.ESTIMATED
No.ITEM DESCRIPTION UNIT QUANTITY UNIT COST ITEM COST
New / Remove and Dispose of Existing Storm Sewer LF 4,580 $20.00 $91,600.00
Additional Remove and Dispose of Existing Manhole/Catch Basin Each 22 $850.00 $18,700.00
Pipe Capacity 24" RC Pipe Sewer (Furnish and Install) (12 - 13' depth)LF 728 $120.00 $87,360.00
36" RC Pipe Sewer (Furnish and Install) (8 - 13' depth)LF 710 $180.00 $127,800.00
48" RC Pipe Sewer (Furnish and Install) (15' depth)LF 368 $300.00 $110,400.00
60" RC Pipe Sewer (Furnish and Install) (8 - 10' depth)LF 840 $320.00 $268,800.00
60" RC Pipe Sewer (Furnish and Install) (10 - 16' depth)LF 2,630 $400.00 $1,052,000.00
Construct Drainage Structure SD-48 LF 434 $450.00 $195,300.00
Construct Drainage Structure SD-60 LF 56 $730.00 $40,880.00
Construct Drainage Structure SD-72 LF 14 $970.00 $13,580.00
Construct Drainage Structure SD-84 LF 224 $1,360.00 $304,640.00
Casting Assembly Each 52 $800.00 $41,600.00
Tie-In Storm Sewer Main to Manhole Each 9 $1,000.00 $9,000.00
Connect CB Leads to Constructed Storm Sewer Each 68 $700.00 $47,600.00
Pump System
Opti CMAC Predictive Pumping Control System (Furnish and
Install)Each 1 $85,000.00 $85,000.00
For Weber
Pond
4,000 GPM Pumping Station (Includes Building Structure, Electric
Supply, Control Panel)LS 1 $700,000.00 $700,000.00
Pumping Station Outlet Piping (Furnish and Install)LF 1,100 $40.00 $44,000.00
Pumping Station Inlet Suction Piping (Furnish and Install)LF 100 $40.00 $4,000.00
CONSTRUCTION SUBTOTAL $7,809,000.00
CONSTRUCTION CONTINGENCY (30%)$2,343,000.00
ESTIMATED CONSTRUCTION COST $10,152,000.00
ENGINEERING, DESIGN, PERMITTING, AND CONSTRUCTION
OBSERVATION (10%)$1,015,000.00
RESIDENTIAL/CONSTRUCTION PERMANENT EASEMENT $56,000.00
ESTIMATED TOTAL PROJECT COST $11,223,000.00
-30%$7,857,000.00
50%$16,835,000.00
Notes
6 Estimate costs are to design, construct, and permit each alternative. The estimated costs do not include maintenance, monitoring or additional tasks following
construction.
7 Furnish and Install pipe cost per lineal foot includes all trenching, bedding, backfilling, compaction, and disposal of excess materials
8 Estimate costs are reported to nearest thousand dollars.
ESTIMATED ACCURACY RANGE
1 Limited Design Work Completed
2 Quantities Based on Design Work Completed.
3 Unit Prices Based on Information Available at This Time.
4 Minimal Soil and Field Investigations Completed. Costs do not included remediation of contaminated soils (if found).
5 This feasibility-level (Class 4, 10-15% design completion per ASTM E 2516-06) cost estimate is based on feasibility-level designs, alignments, quantities and unit
prices. Costs will change with further design. Time value-of-money escalation costs are not included. A construction schedule is not available at this time.
Contingency is an allowance for the net sum of costs that will be in the Final Total Project Cost at the time of the completion of design, but are not included at
this level of project definition. The estimated accuracy range for the Total Project Cost as the project is defined is -30% to +50%. The accuracy range is based on
professional judgement considering the level of design completed, the complexity of the project and the uncertainties in the project as scoped. The contingency
and the accuracy range are not intended to include costs for future scope changes that are not part of the project as currently scoped or costs for risk
contingency. Operation and Maintenance costs are not included.
P:\Mpls\23 MN\27\23271798 Morningside FRR Prelim Eng & E\WorkFiles\Cost Benefit methods\Engineers Opinion of Probable Cost_20201203.xlsx 4
PREPARED BY: BARR ENGINEERING COMPANY SHEET:1 OF 5
BY:CDA DATE:8/27/2020
FEASIBILITY STUDY CHECKED BY:KJN2 DATE:12/3/2020
ENGINEER'S OPINION OF PROBABLE PROJECT COST APPROVED BY:DATE:
PROJECT:Morningside FRR Preliminary Engineering ISSUED:DATE:
LOCATION:City of Edina ISSUED:DATE:
PROJECT #:23/27-1798.00 ISSUED:DATE:
OPINION OF COST - SUMMARY ISSUED:DATE:
Engineer's Opinion of Probable Project Cost
Morningside Flood Mitigation Feasibility Project
REFINED COMBINATION OPTION at ~$5M
Cat.ESTIMATED
No.ITEM DESCRIPTION UNIT QUANTITY UNIT COST ITEM COST
General Mobilization/Demobilization (<10%)LS 1 $500,000.00 $500,000.00
Temporary Erosion Control LS 1 $30,000.00 $30,000.00
Flotation Silt Curtain LF 450 $11.00 $4,950.00
Excavate Excavation CY $4.00 $0.00
Weber Pond Off Site Disposal of Excavated Material CY $18.00 $0.00
Dewatering LS $50,000.00 $0.00
Excavate Tree 2", B&B Each 90 $500.00 $45,000.00
Weber Woods Clearing and Grubbing AC 3 $8,500.00 $25,500.00
Excavation CY 26,000 $4.00 $104,000.00
Off Site Disposal of Excavated Material CY 26,000 $18.00 $468,000.00
Lower Sport Excavation CY $4.00 $0.00
Fieds in Park Off Site Disposal of Excavated Material CY $18.00 $0.00
Turf Establishment (w/ Disc Anchored Mulch)AC $3,000.00 $0.00
Erosion Control Blanket SY $3.00 $0.00
Remove and Rebuild 3 baseball diamonds LS $300,000.00 $0.00
Excavation CY $4.00 $0.00
Off Site Disposal of Excavated Material CY $18.00 $0.00
Turf Establishment (w/ Disc Anchored Mulch)AC $3,000.00 $0.00
Erosion Control Blanket SY $3.00 $0.00
Remove and Rebuild ice hockey rink area LS $50,000.00 $0.00
Swale Excavation CY $4.00 $0.00
through Off Site Disposal of Excavated Material CY $18.00 $0.00
Park Upland Native Vegetation AC $5,000.00 $0.00
Erosion Control Blanket SY $3.00 $0.00
Walking Trail LS $7,000.00 $0.00
Avail Excavation CY $4.00 $0.00
Academy Off Site Disposal of Excavated Material CY $18.00 $0.00
Excavation Tree 2", B&B Each $500.00 $0.00
Clearing and Grubbing AC $8,500.00 $0.00
Upland Native Vegetation AC $5,000.00 $0.00
24" RC Pipe Sewer (Furnish and Install) (12 - 13' depth)LF $120.00 $0.00
Inglewood 36" RC Pipe Sewer (Furnish and Install) (8 - 13' depth)LF $180.00 $0.00
Construct Drainage Structure SD-60 LF $730.00 $0.00
Tie-In Storm Sewer Main to Manhole Each $1,000.00 $0.00
Susan Excavation CY $4.00 $0.00
Lindgren Off Site Disposal of Excavated Material CY $18.00 $0.00
School Turf Establishment (w/ Disc Anchored Mulch)AC $3,000.00 $0.00
Park Erosion Control Blanket SY $3.00 $0.00
10' W x 4' H Box Culvert (Furnish and Install)LF $650.00 $0.00
Open Space Excavation CY 29,000 $4.00 $116,000.00
Number 5 Off Site Disposal of Excavated Material CY 29,000 $18.00 $522,000.00
10' W x 4' H Box Culvert (Furnish and Install)LF 0 $650.00 $0.00
Dewatering LS 1 $50,000.00 $50,000.00
P:\Mpls\23 MN\27\23271798 Morningside FRR Prelim Eng & E\WorkFiles\Cost Benefit methods\Engineers Opinion of Probable Cost_20201203.xlsx 5
PREPARED BY: BARR ENGINEERING COMPANY SHEET:1 OF 5
BY:CDA DATE:8/27/2020
FEASIBILITY STUDY CHECKED BY:KJN2 DATE:12/3/2020
ENGINEER'S OPINION OF PROBABLE PROJECT COST APPROVED BY:DATE:
PROJECT:Morningside FRR Preliminary Engineering ISSUED:DATE:
LOCATION:City of Edina ISSUED:DATE:
PROJECT #:23/27-1798.00 ISSUED:DATE:
OPINION OF COST - SUMMARY ISSUED:DATE:
Engineer's Opinion of Probable Project Cost
Morningside Flood Mitigation Feasibility Project
REFINED COMBINATION OPTION at ~$5M
Cat.ESTIMATED
No.ITEM DESCRIPTION UNIT QUANTITY UNIT COST ITEM COST
New / Remove and Dispose of Existing Storm Sewer LF 3,000 $20.00 $60,000.00
Additional Remove and Dispose of Existing Manhole/Catch Basin Each 22 $850.00 $18,700.00
Pipe Capacity 24" RC Pipe Sewer (Furnish and Install) (12 - 13' depth)LF 728 $120.00 $87,360.00
36" RC Pipe Sewer (Furnish and Install) (8 - 13' depth)LF 330 $180.00 $59,400.00
48" RC Pipe Sewer (Furnish and Install) (15' depth)LF 0 $300.00 $0.00
60" RC Pipe Sewer (Furnish and Install) (8 - 10' depth)LF 0 $320.00 $0.00
60" RC Pipe Sewer (Furnish and Install) (10 - 16' depth)LF 2,630 $400.00 $1,052,000.00
Construct Drainage Structure SD-48 LF 434 $450.00 $195,300.00
Construct Drainage Structure SD-60 LF 56 $730.00 $40,880.00
Construct Drainage Structure SD-72 LF 14 $970.00 $13,580.00
Construct Drainage Structure SD-84 LF 224 $1,360.00 $304,640.00
Casting Assembly Each 52 $800.00 $41,600.00
Tie-In Storm Sewer Main to Manhole Each 9 $1,000.00 $9,000.00
Connect CB Leads to Constructed Storm Sewer Each 68 $700.00 $47,600.00
Pump System
Opti CMAC Predictive Pumping Control System (Furnish and
Install)Each $85,000.00 $0.00
For Weber
Pond
4,000 GPM Pumping Station (Includes Building Structure, Electric
Supply, Control Panel)LS $700,000.00 $0.00
Pumping Station Outlet Piping (Furnish and Install)LF $40.00 $0.00
Pumping Station Inlet Suction Piping (Furnish and Install)LF $40.00 $0.00
CONSTRUCTION SUBTOTAL $3,796,000.00
CONSTRUCTION CONTINGENCY (30%)$1,139,000.00
ESTIMATED CONSTRUCTION COST $4,935,000.00
ENGINEERING, DESIGN, PERMITTING, AND CONSTRUCTION
OBSERVATION (10%)$494,000.00
RESIDENTIAL/CONSTRUCTION PERMANENT EASEMENT $56,000.00
ESTIMATED TOTAL PROJECT COST $5,485,000.00
-30%$3,840,000.00
50%$8,228,000.00
Notes
6 Estimate costs are to design, construct, and permit each alternative. The estimated costs do not include maintenance, monitoring or additional tasks following
construction.
7 Furnish and Install pipe cost per lineal foot includes all trenching, bedding, backfilling, compaction, and disposal of excess materials
8 Estimate costs are reported to nearest thousand dollars.
ESTIMATED ACCURACY RANGE
1 Limited Design Work Completed
2 Quantities Based on Design Work Completed.
3 Unit Prices Based on Information Available at This Time.
4 Minimal Soil and Field Investigations Completed. Costs do not included remediation of contaminated soils (if found).
5 This feasibility-level (Class 4, 10-15% design completion per ASTM E 2516-06) cost estimate is based on feasibility-level designs, alignments, quantities and unit
prices. Costs will change with further design. Time value-of-money escalation costs are not included. A construction schedule is not available at this time.
Contingency is an allowance for the net sum of costs that will be in the Final Total Project Cost at the time of the completion of design, but are not included at
this level of project definition. The estimated accuracy range for the Total Project Cost as the project is defined is -30% to +50%. The accuracy range is based on
professional judgement considering the level of design completed, the complexity of the project and the uncertainties in the project as scoped. The contingency
and the accuracy range are not intended to include costs for future scope changes that are not part of the project as currently scoped or costs for risk
contingency. Operation and Maintenance costs are not included.
P:\Mpls\23 MN\27\23271798 Morningside FRR Prelim Eng & E\WorkFiles\Cost Benefit methods\Engineers Opinion of Probable Cost_20201203.xlsx 6