HomeMy WebLinkAboutItem IV - Landscaping Improving Stormwater Management in
Oshkosh Through Green Infrastructure
Environmental Studies Senior Seminar
University of Oshkosh Wisconsin
Landscaping Group
Lexie Uffenbeck, Caitlyn Uhlenbrauck, Grant Zweig, Hannah Holzschuh, Ben Slusser
May 2018
r
11, L
61,
r
.%" f
Table of contents:
• Executive Summary......................................................................................................................2
• Introduction...................................................................................................................................3
• Identification of problem.............................................................................................................3
• Background....................................................................................................................................4
• Proposed action............................................................................................................................8
• Stakeholders................................................................................................................................10
• Case Studies.................................................................................................................................20
• Cost...............................................................................................................................................23
• Barriers.........................................................................................................................................24
• Significance of sustainability.....................................................................................................26
• Conclusion...................................................................................................................................27
• References...................................................................................................................................31
1
Executive summary:
The landscaping techniques we propose involve different levels of difficulty, costs, and
their own individual barriers. The techniques we want to implement are rain gardens,
bioswales, green roofs, and vertical plantings. Behind all of these techniques is a dependence on
soil series which determine the different beneficial qualities for the area. Each soil series
contains a different amount of silt, sand, and clay which affects the type of landscaping and
materials that can placed in the area. The basis of these ideas comes from the city of Oshkosh
Sustainability Plan, the Green Tier Community document, and extensive research on the use of
green infrastructure. Oshkosh is a certified Green tier Community, a part of Tree City USA, and
has high flyer status through Bird City. This shows how Oshkosh is dedicated to being
sustainable and how implementing the landscaping methods we are recommending are a
feasible change for the city. We talked to several stakeholders to gauge their opinion on the
ideas we are proposing and to see how viable these ideas are. A large portion of the following
report is spent explaining each landscaping technique and where these methods will be best
utilized. Before moving forward, it is also important to address what barriers and costs we may
encounter and how to overcome them. Through our research and audit of the city of Oshkosh,
we would like to propose numerous landscaping techniques to implement, especially in parking
lot design, to improve stormwater management, reduce runoff, and improve water quality.
2
Introduction:
Within the city of Oshkosh there is a need for more green infrastructure. As a
community that is a Tree and Bird City, and a Green Tier Community, we must uphold this
prestige by maintaining and improving our green infrastructure. We find the issue of green
infrastructure relevant to the issue of stormwater management and relevant to parking.
Through our research, we find that different techniques of landscaping can aid in trapping and
filtering stormwater before entering the sewer systems and groundwater.These landscaping
techniques include bioswales, rain gardens, native plants, and vertical plantings. By
implementing our recommendation of how to manage stormwater, we will see improved water
quality, reduced runoff, less flooding, and lower stress on sewer systems.
Identification of the Problem:
Stormwater drainage issues are seen mostly in parking lots with impervious surfaces.
Stormwater runs off of impervious surfaces and into water bodies. There are very high rates of
eutrophication in Lake Winnebago and the Fox River. These water bodies around Oshkosh have
increasingly high levels of limiting nutrients like nitrogen and phosphorus; causing algal blooms
and accelerating the lifetime of the lakes. Additionally, the water running off of impervious
surfaces and the low absorbance of water in turf grass around the city causes flooding in yards,
streets, and basements.
Local pollution from brownfield sites pollutes the soil and groundwater. Brownfields are
areas that are contaminated with various pollutants that impact public health and prevent or
3
slow development (Mikkelsen et. al 1994). It is important to prevent contamination of water
that originates from runoff of these sites because many of these contaminants will persist in the
water and soil for very long periods of time and cause a variety of negative health impacts to
humans and the ecosystem.
Background:
Soil varies greatly depending on different factors such as climate, moisture regime, and
geological history. Each soil series and type of soil varies in composition of sand, silt, and clay.
These three components and the composition percentages create the different types of soil.
,f
IN
of I
� D
u I
s
Figure 1.1: City map of Oshkosh map with NRCS data overlay
Figure 1 shows a map of the city of Oshkosh with an overlay of NRCS soil data. The
yellow lines depict the borders for different soil series in the area. For the city of Oshkosh there
are many different soil series each with a different soil profile and description with qualities that
4
determine the types of plants that can grow in that area or the amount of infiltration. It
determines the depth to the water table and within the different soil types are variations
amongst the availability of water intake and the amount of water that stays within the top soil
layers. Depending on soil composition and the amount of air space between each aggregate,
the water will trickle and slowly filter toxins out before entering the water table. At the base of
any landscaping technique implementation, there needs to a a qualitative analysis of the soil
underneath the area along with an accurate site label, such as brown, etc. At the corner of
Butler and Snell there is a designated brown site, which means that this area is polluted and
therefore compromised and in need of restoration (Soil management plan, 2012).This area is
contaminated by petroleum. The basis of soil health and contamination is something that is
required to know before trying to remediate the area. For example, certain native plants will be
able to hold up to pollution better than others and eventually filter those toxins out of the soil
through uptake from the soil. The importance of soil and knowing the condition of the soil can
make a restoration process go much smoother and therefore lead to the success of landscaping
techniques in the system.
Native plants with deep roots hold the soil together, prevent erosion and runoff, do not
require the use of pesticides and fertilizers, and overall do not require much maintenance
(Hefland et. al 2006). Additionally, they increase biodiversity which benefits the environment in
a number of ways as well as provides beauty and brings a natural sense of place and belonging
to this area. The ecotone in Oshkosh is traditionally oak savanna which contains many deep
rooted grasses. These grasses grow a complex root systems that hold the soil together and soak
up water from the surface. Along shorelines, a buffer of deep rooted native plants will prevent
5
soil erosion which causes turbidity and poor water quality. Using native grasses in all parts of
city, in addition to along water bodies, is beneficial and helps to conserve the quality of an
important natural resource - water. Native plants have evolved with other species in the
ecosystem which means they are better suited to handle the different climate events in this
area. Hasselkus, E. R. (2012) is a good reference for what types of plants are native to Oshkosh,
what their different benefits entail, and where to place them based on the habitat and soil type.
This will not only guide the city on how to better understand the ecosystem and types of plants,
but also residents who want to implement native plants on their own property. The benefits of
native plants outweigh non-native plants. They provide structure for the soil and they are
adapted to this ecosystem so they are better suited for the climate and therefore require less
maintenance and resources.
Rain gardens are a sufficient solution for stormwater best management practices
(BMPS). A rain garden is a depressed area that collects water from runoff(Asleson, 2009). They
are planted with grasses and flowering plants. Some of the major benefits include being cost
effective, aesthetically pleasing, reducing runoff, filtering pollutants, and creating habitat for
wildlife (Asleson, 2009). Bioswales achieve the same goals as rain gardens but are designed to
manage a specified amount of runoff from a large impervious area, such as a parking lot or
highway. Bioswales often deeper than rain gardens but use the same native plants to withstand
both heavy rains and drought (Soil Science Society of America, 2018). The use of rain gardens
and bioswales will provide useful bioretention for positive drainage. Rain gardens and bioswales
are a great step toward introducing green infrastructure. We need to first implement
sustainable stormwater infrastructure. Then, begin planning and policy to connect ecological
6
aspects. These bioretention methods will also feature native plantings that will create habitat
and be aesthetically pleasing to the citizens of Oshkosh. We can also work with large
corporations to implement rain gardens and bioswales on commercial property. For example,
Oshkosh truck is building their new headquarters in Oshkosh and by using green infrastructure
on their property, they can be a leading example in the city for other businesses. Oshkosh Truck
is especially significant because their new headquarters will be positioned on two bodies of
water. Rain gardens and bioswales are effective at capturing water that typically runs off of the
land and into the water. Working with businesses around the city to implement rain gardens and
bioswales on their properties is an effective stormwater management practice.
Preserving what we already have, the City of Oshkosh Sustainability Plan outlines that
the retention of existing trees and other vegetation is a goal for the city now and in the future.
We would like to reiterate the importance of maintaining that vegetation within Oshkosh and
ensuring that any new developments that take place in the city are mindful of Oshkosh's
commitment to retaining native vegetation. Ensuring that new developments are following
recommendations and guidelines will help Oshkosh maintain its Tree City USA status along with
making it a healthier and more sustainable city. The benefit of retaining our Tree City USA status
requires us to maintain the trees we already have, but we recommend these trees are native
and have the deep rooted systems made for this environment and climate so they will benefit
the other species in the ecosystem and maintain a clean environment ( Berland et. al 2017).
Native trees placed along our street frontages will help increase infiltration. Placing native trees
along street frontages will reduce soil compaction from the impervious surfaces and increase
infiltration during rain events. (Bartens et. al 2008). Combining all of the landscaping methods
7
mentioned will create the best stormwater management practice and greatest benefit for the
environment.
Proposed Action:
In order to protect our water resources, reduce runoff, and prevent flooding within the
city, we recommend three changes to the landscaping ordinance. In Article IX, Chapter 30 of the
city of Oshkosh ordinances describes a point system that requires public and commercial land to
meet a certain number of points which are assigned to different landscaping features. Currently,
the point system is not used directly to manage stormwater and residential areas are excluded.
We have also found that there are more parking lots than are being utilized in Oshkosh which
contributes to more runoff into the waterways. When rain gardens, bioswales, and other
landscaping features are added to parking lots, streetscapes, and other areas of the city, the
amount of runoff is reduced. The amount varies depending on how much landscaping is added
to an area, considering flow rate, slope of incline, soil type, and the severity of the rain event,
but green infrastructure and sustainable landscaping will have a positive impact on stormwater
management within the city. Overall, Oshkosh needs to implement a more developed point
system which favors green infrastructure in order to strengthen stormwater management to be
the best management strategies.
As the landscaping team for the University of Wisconsin-Oshkosh Environmental Studies
Senior Seminar capstone we suggest the city implement an extension of the point system found
8
in Article IX, Chapter 30 of the Oshkosh Municipal Code. The city of Oshkosh Municipal Code
states that the purpose of the Landscaping Requirements chapter is to "establish landscaping
requirements and other regulations intended to preserve and maintain vegetation within in a
manner that promotes the natural resource protection, aesthetic, and public health goals of the
City."The point system is used as a way to enforce specific landscaping techniques on
commercial and public lands in Oshkosh. Reaching a certain amount of points per area (which
differs depending on the land use) is required under the Landscaping Requirements ordinance.
The ordinance lays out how to reach the minimum amount of points required by assigning
points to different types of plants, shrubs, trees, fencing, and more. To further align with the
mission of Oshkosh and promote ecosystem health, these are the potential changes we propose
be made to the Landscaping Requirements:
We request that the city implement within article IX section 30-253, item (2) paved
areas. For paved areas we want to alter the current plan from 40% of shrubbery requirements
to 40% native shrubs only. Second to that, we want article IX section 30-255 item (3) street
frontages. Within street frontages the minimum of 50% of all points are devoted to decorative
and medium trees and we want to change this to be 30% native trees and a minimum of 30%
must be deep rooted native grasses. We believe that native plants are better to manage
stormwater than trees. Article IX section 30-255 item (2) requirements part (A): currently
bioswales and rain gardens get 20 points per 20 square ft. area and cannot exceed 100 points.
We are requiring this be changed to 30 points per 20 square ft. area with no point limit.
We would also like to see changes to Section 30-251: Applicability (B). This section
asserts that any expansion of existing buildings exceeding 50% of the current building's floor
9
area are required to follow the landscaping requirements listed in Chapter 30 -Article IX. We
recommend that this figure be reduced to 25% of the current building's floor area. This means
that if the expansion of the existing building exceeds one quarter of the the building's current
floor area, the owner(s) will be required to adhere to the requirements listed in Chapter 30 -
Article IX.
Finally, we recommend an amendment to Section 30-251: Applicability (E) Exemptions.
This section has exempted single family and two family dwellings from meeting landscaping
requirements. We propose that newly developed single and two family dwellings be included in
the landscaping requirements upon construction.
Stakeholders:
We met with a variety of people in Oshkosh and the surrounding communities to gain
insight into their perspectives on various parts of the community in order to better understand
how they perceive the landscaping ideas we are proposing. In addition, we desired to discover
how viable these options are by gauging community acceptance.
I. Steven Wiley,Assistant Planner of the City of Oshkosh
One of the primary stakeholders we interviewed was Steven Wiley, who is the assistant
planner for the City of Oshkosh. Mr. Wiley is an important stakeholder for the Landscaping
group because he is knowledgeable about how different parts of Oshkosh are implementing
green infrastructure, where improvement needs to happen, and how feasible some of our ideas
are in regards to current regulations. He had a lot of really great things to say that were very
helpful in creating our recommendation for the city. The topics we focused on from his
10
interview are community planning, natural assets in Oshkosh, hazards, stormwater regulation,
current green infrastructure usage, how willing the community is to accept those features in the
City, and how everything ties into community identity and character.
Mr. Wiley discussed that there was a comprehensive plan in place that is currently being
updated. It addresses Oshkosh's natural resources as important for agriculture, nature, and
culture.The plan outlines a need for green infrastructure through conservation of resources,
with special attention to our water supply (i.e. watersheds, runoff issues, navigable waters and
erosion from wake, groundwater, drinking water, and floodplain and wetland zoning districts).
Although there have not been any formal wetland restoration projects that have taken place in
Oshkosh (to the best of Mr. Wiley's knowledge), the comprehensive plan does give suggestions
on how to do so were one to be undertaken.
Oshkosh has many resources including rivers, streams, lakes, property on the water, and
other natural areas such as Sawyer Creek and Miller's Bay. As Mr. Wiley mentioned previously,
Oshkosh's resources bring a sense of culture to the city. Volunteers from all over Oshkosh came
together to help restore the Miller's Bay Mainly through native plantings with the goal to
maintain a healthy environment and an attractive appearance. Steven also suggested that the
Pioneer site in Oshkosh would be a suitable site for restoration and implementation of green
infrastructure. Another initiative that has brought together the community is implementation of
a stormwater medallion near stormwater drains that educates the community on what should
not be dumped into those stormwater drains that run directly into local bodies of water.
An unfortunate topic that has to be brought up when discussing stormwater drainage, is
hazards. Oshkosh has had many flooding issues including basements backups, wet basements in
11
homes, street flooding, and flooding in yards and other green spaces. Steven was not sure that
there have ever been beach closures because of high levels of bacteria, but it is not necessarily
always safe to swim in the water. In Lake Winnebago, there are high levels of phosphorus, PCBs,
and suspended sediment. The Fox River is in slightly better shape with low levels of PCBs and
aquatic toxicity.
Perhaps the most important part of the interview with Mr. Wiley in relation to this
project, was of discussion of stormwater regulations. The stormwater ordinance is up to date
and does offer some incentives for green infrastructure. Examples of these incentives include
credit given to property owners who have city-approved rain barrels and rain gardens (and an
extra credit given for property on the water), a best management practice credit, and a credit
given to those who improve the quality of the runoff from their land. Native plants and rain
gardens are noted in the stormwater ordinance, but there is little to no mention of green roofs
and permeable pavers - both of which are important to groups in this class. Overall, Steven said
that using green infrastructure to reduce infrastructure is not discouraged, but it is definitely
not as encouraged as it perhaps should be. In all of these categories, Oshkosh is doing a fair job
at focusing on environmental impact, but there remains room for improvement.
It is important to consider what has already been implemented in and around the City of
Oshkosh when planning what we would like to propose to the City for our portion of the final
project. Two of the most noteworthy green infrastructure features that were discussed in our
interview with Mr. Wiley were rain barrels and rain gardens. Perhaps due to the simplicity of
installation and their low maintenance requirements, rain barrels seem to be the more
prevalent feature implemented by residents. Such features do not require a permit to be
12
installed, but in order to obtain the stormwater utility credit that the City offers, a permit must
be submitted by those seeking the credit. Along with rain gardens and rain barrels, Mr. Wiley
noted some of the other green infrastructure features that can be found in the City of Oshkosh
including, bioretention areas, green roofs, permeable surfaces, bioswales, and native plantings.
Overall, residents have been fairly accepting of green infrastructure features in the City
of Oshkosh. However, it was discussed that concerns related to such projects usually arise
around their cost. For the most part, residents are open to green infrastructure projects so long
as they are not overly expensive. Additionally, there has been some controversy surrounding the
Friends of Menominee Park Shoreland restoration project. The dominant issue with this project
has not been the cost, rather it has been that the native plants that have been planted are
supposedly blocking some residents' view of Lake Winnebago and therefore some want to see
those plants either removed, trimmed, or replaced with shorter vegetation.
Although there is acceptance of some of the most common green infrastructure features
in the City of Oshkosh, it was discussed that the community's identity and character do not
necessarily reflect green infrastructure and landscaping. There is a small portion of the
population of Oshkosh that is interested in taking on such projects; however, there appears to
be a much larger portion that simply is unaware of such issues and projects. Steven also noted
that developers may be aware of such features but typically stick to what they are used to,
which does not usually involve green infrastructure. Even though there may not be widespread
interest, Oshkosh seems to be changing for the better. Part of this change comes in the form of
Oshkosh being designated a Tree City USA, receiving High-Flyer statues through Bird City, and
being a Green Tier Legacy Community. There are also various allies to green infrastructure and
13
environmental initiatives including Silverstar Brands, the Southwest Rotary Club, Oshkosh Corp.,
the Oshkosh Public Library, Friends of the Menominee Park Shoreland, and others.
II. Margy Davey, Head of the Sustainability Board for the City of Oshkosh
Along with Steven Wiley, Margy Davey is a primary stakeholder. Margy is a primary
stakeholder to the landscaping group because she works directly with the city of Oshkosh on
the Sustainability Advisory Board. Margy showed concern that although the community's
natural resources are addressed in the comprehensive plan, they are not given as much
attention as they should be getting. She states that the city could be doing a lot better with
specific attention to the community's water resources in the comprehensive plan. In relation to
stormwater, she mentioned that although inflow and infiltration has improved, many residents
of Oshkosh still struggle with flooding. She mentioned that a major issue with the landscaping
point system, is how it is set up. Currently, trees gets more points than native plants even
though native plants would help mitigate stormwater runoff better because of their deep root
systems and coevolution with other species in the ecosystem.
Ms. Davis stated that the main problem is that other departments do not realize that
there is a Sustainability Advisory Board which will do research for them. The Sustainability
Advisory Board and Parks Department do not have a close relationship, but Ms. Davis believes
that if they could work together, they would get a lot more accomplished. On a more positive
note, she acknowledged that the community is very involved with the Sustainability Advisory
Board by asking questions and demanding that more be done.
14
Since the community seems to be engaged with the board, we asked her if being "green"
is attractive to new people moving into the area. Ms. Davis said that, that was a good question,
and that she does not know. What she does know is that the board has spent months on green
events that provide information for people that want to be green. She once again voiced her
concern and frustration that they do not get any recognition from the city for holding such
events.
Specific environmental initiatives that have been started in the community that relate to
the green events are rain gardens and rain barrel workshops. Fox-Wolf River Shed Rain Barrel
workshops are more popular than the rain gardens. Ms. Davis is happy that there is a workshop
for people to attend but she wishes that they either they make it shorter and more concise or
make it long and go into greater detail. The workshop provides barrels, kits, and information on
how to set everything up. The issue she discussed is that there is confusion with the stormwater
credit that is in place. She is pretty certain that participants have to fill out paperwork to have
the rain barrels on their property to get the stormwater credit but no one keeps track of
whether they actually set up and are using it. In addition to the rain gardens and rain barrel
workshops in the community, there may be some community gardens but she is unsure of
where the water comes from to maintain the gardens.
Ms. Davis brought up that she has contacted hotels in the area to see which hotels claim
to be "green" and what makes them green. What makes the hotels green include, asking guest
their if they want their sheets washed everyday during their stay. Another way they are being
green is by the landscaping techniques they are implementing. She wanted to put hotels and
restaurants that are "green" in a brochure for tourists. Her logic was that by promoting "green"
15
companies, they would be rewarded with an increase of tourists going there.
Another issue she discussed in the city is shoreline preservation. Ms. Davis would like to
see more native vegetation buffers planted in Menomonee Park. There is terrible algae in
Miller's Bay and as a way to combat this, a restoration project was completed to implement
native vegetation.
We asked if residents of the City of Oshkosh like a homogeneous appearance to their
neighborhoods or if individual residents' preferences are tolerated or are celebrated. Ms. Davis
noted that a majority of Oshkosh looks similar and most have short turf grass which have very
short root systems. However, there are some residents that have native plants and keep up with
them. She wishes that there was more education for citizens so they could realize the
importance of native plants - especially those that have property on the water. She believes that
they should take more initiative and learn about such plants. Even if they used a "soft" buffer
zone, it would be better than nothing.
Overall, issues that she voiced revolve around people not understanding the advantages
of green infrastructure and other environmental initiatives, along with the fact that politics
complicates things and slow down the process. In future, she hopes the community will become
more informed about such issues. In order to educate citizens, she offered a few methods. First,
she mentioned a cellphone app called POLCO which can be used to ask questions about
anything environmental. Another way she noted on how to reach and educate people is through
the mail and social media sites, like Facebook. She wanted to voice special concern that it is
important to take into consideration the fact that there are 78 different languages spoken in the
Oshkosh area and it is a necessity to make all of this information accessible to all of the
16
residents in Oshkosh. Interviewing Ms. Davis was valuable for this project because she gave us
insight into how the community reacts to native landscaping, if residents are implementing
these practices already, and noted how education, communication, and accessibility is key to
being successful.
III. Bruce Bartel, District Director at Northeast Wisconsin Water
Bruce Bartel is the District Director/Treatment Manager for Northeast Wisconsin Water
(N.E.W Water). Interviewing him gave us insight into what activities are occurring downstream
of the Fox River to better the watershed. N.E.W Water is a Metropolitan Sewerage District but
they also clean water from the bay of Green Bay that they use for their drinking water. Because
the Fox River flows north, Green Bay receives the effluent from Oshkosh and other cities
downstream so it is important that we work to better our water quality in the watershed as a
whole.
Mr. Bartel talked about how Oshkosh wastewater had been hit with a high demand for
phosphorus reduction from their effluent flow. The consequences of not reducing meant they
will not be permitted by the Wisconsin Department of Natural Resources (WDNR) anymore. In
order to combat this, N.E.W Water has been undergoing several large scale renovations on their
campus that Mr. Bartel was excited to tell us about. When the plans were being drawn up, there
were some intense negotiations going on about which route to take. The two choices were to
focus more on the campus, expand and buy new technology, or to place money into the
community and work on adaptive management through the introductions of new green
infrastructure to their campus and new technology. The adaptive management route was
17
chosen. They are currently working on restoring Silver Creek and implementing rain gardens all
throughout the city of Green Bay. Additionally, they are pushing for larger buffer zones along
shorelines and want to lay down permeable pavements. This will help filter water that runs off
of their campus which tends to be especially polluted due to wastes that are dropped off and
they do not want to risk contamination of the groundwater supply. Overall, N.E.W Water is
setting a great example and have high standards for the rest of the watershed. Mr. Bartel said
they are seeing significant benefits from the adaptive management approach and hope to see
Oshkosh start implementing some of these techniques to better the watershed as a whole.
Although N.E.W. water is a secondary stakeholder, we can learn a lot from their own
decision to implement adaptive management and community involvement with green
infrastructure as a method to better manage their stormwater runoff problem. Overall, this
interview provided us with a local example of a city and company that is affluent enough to
implement change in their city to better handle stormwater runoff. They have taken on huge
projects and said they are still working to better green infrastructure and stormwater
management in the city.
IV. Brian M. Helminger, Heart of the Valley- District Director (Kaukauna)
The next stakeholder we met with was the district director at Heart of the Valley, Brian
M. Helminger. The main goal of this interview was to get a better understanding of how
different areas of the same watershed are influenced by the actions of others. We asked about
the current methods that Heart of the Valley is using to reduce stormwater runoff, examined
landscaping alternatives, and discussed potential barriers.
18
We first discussed how pollution multiplies as water heads downstream. Whatever
happens upstream will impact what goes on downstream. Oshkosh is upstream of Kaukauna
and Kaukauna is upstream of N.E.W Water in Green Bay so we met Mr. Helminger to further
explore this trend and how it affects Oshkosh. Mr. Helminger explained that total suspended
solids or (TSS) is the biggest issue that the plant faces. The Department of Natural Resources
(DNR) sets various water quality standards such as TSS. We asked Mr. Helminger if his plant was
conducting any adaptive management methods to reduce stormwater runoff and he told us that
the only method they used was water retention ponds. He admitted that the community does
not favor having retention ponds near their property and it actually brings down their property
value. This makes sense because a large concrete hole with dirty standing water is not exactly
aesthetically pleasing. As an alternative, we asked about the use of rain gardens. He agreed that
rain gardens are a good idea that the community would be more willing to accept, but his main
concerns with rain gardens were the continued maintenance and initial cost associated with
them. This was a notable point that we revisited when forming our recommendation for
Oshkosh and overcoming our barriers.
A main barrier for small towns like Kaukauna to invest in green infrastructure is the cost
of doing so. Mr. Helminger said that "Europe is more willing to roll the dice on green
infrastructure" because of their larger budget. This is true, however we came to the conclusion
that cities would ultimately be paying less if they worked in tandem with natural processes. The
hardest part of implementing green infrastructure is the initial cost, but after doing so, it will
start to pay off both monetarily and environmentally. When cities utilize natural processes and
ecosystem services, they do not have to pay as much for water treatment, fixing the damage
19
from erosion, and more.This is one of the main driving points that we want the city of Oshkosh
to receive and utilize.
Case Studies:
Examining the implementation of green infrastructure and landscape techniques for
stormwater management in places around the world is important to understand how viable
these methods will be in Oshkosh. The four cities we studied were Prairie Crossing, Illinois,
Seattle, Washington, Milwaukee, Wisconsin, and New York, New York and the country of
Singapore. Each of these locations have used their resources to manage stormwater in a natural
way that improves water quality, reduces runoff, helps the ecosystem, and is aesthetically
pleasing.
The first city we examined was Prairie Crossing, Illinois. We chose this city because it is
close to home - meaning they have a similar ecosystem, weather patterns, soil types, and plant
and animal species. Additionally, the community size is roughly the same as Oshkosh and it has
similar landmarks and land usage (i.e. agriculture, a lake, and natural spaces). Prairie Crossing
introduced their"stormwater treatment train system" which has successfully reduced peak
runoff by more than 60 percent and has reduced annual runoff up to 75 percent by using
different types of green infrastructure within the city (Buranen 2014). They restored 165 acres
of prairie and 20 acres of wetland using native plants. They also planted deep-rooted native
plant species throughout the city which holds the soil together, prevents erosion, absorbs water
that would normally run off, and maintains good water quality. Using native plants also
benefited the city because they did not require fertilizers, pesticides, and do not need to be
watered in comparison to non-native species. Native plants evolved with the soil type, amount
20
of water, and amount of sunlight in its natural habitat, so maintenance after initial planting is
very minimal. Prairie Crossing also used bioswales filled with native plants along streets to
collect and infiltrate polluted runoff coming off the roads. To further protect the quality of the
lake, they created wetland buffer zones using native plants which acted as a biological water
treatment and detention to the lake. The final aspect of the stormwater treatment train system
took into consideration the social aspect of sustainability in managing stormwater: education.
Educational events are put on about how to plant effective bioswales, what native plants should
be used and how to arrange them, and more. The city has adopted an atmosphere of
environmental care -their lake which holds endangered fish is named "Aldo Leopold" and there
street signs reflect other environmentalists and plant species. New home owners and
prospective builders in the city are given a pamphlet about how build "green" houses and grow
a native yard. We know transforming Oshkosh to adopt this environmental culture and changing
the physical state of our yards may take many years, but it is possible. Prairie Crossing, Illinois is
a great example of how a city can significantly reduce stormwater runoff(among many benefits)
through natural landscaping and we know that Oshkosh can do the same.
The second location we examined was Singapore. This is an international example that
can show how a new leader and collective effort can entirely revamp an urban environment.
Singapore's Prime Minister urged the city to move forward with Green in mind and launched a
campaign in the early 2000's. The purpose of the campaign was to become the world's leader in
knowledge and implication of green infrastructure at the city-state's center. They successfully
implemented vertical planting, rain gardens, and overall worked to improve soil health.
Singapore took the initiative to rebrand their city-state to bring in tourism and to better their
21
city-state for their residents. Singapore can provide us with an example of how anywhere can
transform from a gray infrastructural "concrete jungle" to green infrastructure (Karlenzig, 2018).
The associated benefits we have discussed thus far in this report were seen as a result of
Singapore's actions towards using sustainable green infrastructure.
Another city we examined is Seattle, Washington which has taken a slightly different
approach in the landscaping of its city. Seattle aims to accomplish many of the same things that
we do here in Oshkosh, such as improving stormwater management, maintaining the aesthetic
appeal of the city, and improving the health of its residents and the environment. However, one
thing that Seattle is doing different is that they are planting species of vegetation within the city
that can be harvested and used by the residents. This activity, known as urban foraging, is
slowly becoming more popular in major metropolitan areas around the world. Essentially, the
city plants or maintains vegetation that can be harvested by residents and used for food,
medicine, crafts, recreation, and cultural and spiritual practices. By supporting urban foraging in
the city, Seattle is not only being environmentally sustainable by planting vegetation throughout
the city, but it is also be socially sustainable.Just as diverse as the uses of the foragable urban
landscape, are the people who engage in urban foraging. The range of urban foragers can go
from hobbyists who might forage to maintain a connection to nature while in the city, to
lower-income residents who rely on urban foraging to supplement a portion of their income.
Whatever the reason for participating in urban foraging, the practice is a unique way to assist a
city in being socially sustainable, creating and maintaining the social cohesiveness and inclusion
that is a part of being a truly sustainable city(Poe 2014).
22
Our last case study comes from New York, New York. In this case study we were able to
delve into bioswales and the mean retention that they offer. Bioswales are able to fit into tight
spaces within city blocks and they are also able to be implemented into parking lots. When they
are implemented into parking lots, they serve as collection for runoff and filter the small
particulates out before entering the ground water. Bioswales also allow for recharge of the
groundwater. They studied ten bioswales during 185 rain events from Spring 2011 through
Summer 2011 (McLaughlin,2012) . They found that the mean capture rate between ten
bioswales when below one inch of rain fell was 73%. When there was 1.00-2.00 inches of
rainfall, the mean capture rate was 25%. Lastly, when over 2 inches of rain fell, the mean
capture rate was 14%. That makes more a total average of 59% capture rate.
Cost:
The costs associated with implementing green infrastructure will come from installation,
operation, and maintenance within the city of Oshkosh. In this section, we will also explain the
differences in the effectiveness of best management practices (BMPs)versus conventional
systems and the environmental and economic benefits that BMPs and low-impact development
can provide for stormwater management. It is important to look at more than just the up front
installation cost when practicing low-impact development due to the fact that many of these
investments into infrastructure will provide long-term benefits for the city of Oshkosh. Overall,
cost considerations vary greatly based on the user and the project for the per-unit area in
square feet. The cost of building a rain garden will vary based on the size, complexity of the
23
design, surface area, soil quality, and slope of ground (Rain garden alliance, 2018). The
estimated cost for bioretention (rain gardens/ bioswales) was estimated at $1-$5 per square
foot average for "do-it-yourself" prices and $10- $40 per square foot average for professional
prices (Rain garden alliance, 2018). For example, a parking lot with 250 and 125 square foot
planter islands is replaced utilizing professional average installation pricing. Both maximums
and minimums for 250 square foot and 125 square foot planter islands are used. To replace the
planter islands with bioretention areas, the 250 square foot area will cost from $2,500 to
$10,000 dollars. For the smaller 125 square foot planter island, it will cost from $1,250 to
$5,000 dollars. It is important to note that these prices are high and low averages. Surveys will
be needed to get an approximate price for areas within the city of Oshkosh.
Benefits:
The benefits of these best management practices often go ignored as policy makers only
focus on up-front cost. Best management practices are proven to manage stormwater quantity
and quality more effectively than conventional approaches (Coffman et. al., 1999). Examples
include filtering more pollutants, reducing flooding, improving water quality, increasing ground
water recharge, reducing public expenditures on stormwater infrastructure, and enhancing
aesthetics and property values (Asleson, 2009). The reduction of public expenditures on
stormwater infrastructure has been reported by various sources that the use of permeable
surfaces, rain gardens, and bioswales can greatly reduce the demand for conventional
stormwater controls. Some additional benefits of bioretention include lower lifetime costs,
multifunctionality, reduced infrastructure cost, lower maintenance, chemical pollution
24
reduction, protection from flooding, increased wildlife habitat, and overall cost-effective
stormwater management (Coffman et. al., 1999). It is important to look at initial costs as well as
additional costs over a structures lifetime including maintenance and operation. Bioretention
structures, like rain gardens and bioswales, can be left as natural areas at the end of their
functional lifetime whereas high costs may be required to take conventional gray infrastructure
out of commission. During the lifetime of bioretention areas, the maintenance costs are
minimal and just require ensuring that drainage areas are kept clear (Coffman et. al., 1999).
Utilizing ecosystem services gained from natural landscaping will also reduce infrastructure cost
in the city of Oshkosh. Bioretention practices can be incorporated in a wide variety of places,
like along streets, which will take less time and require less labor than traditional drainage
piping systems. Additionally, bioretention improves water quality by allowing filtration of
pollutants from water when it seeps through the soil and root system of the plants. To maximize
the infiltration of water, it is recommended to use plants with long root systems native to the
area. Chemicals are filtered in the roots and soil in bioretention areas. The soil in rain gardens
interact with pollution using two main processes: absorption and volatilization. Volatilization
occurs when the pollutants evaporate and adsorption occurs when the pollutants stick to soil
particles (Dietz & Clausen, 2006). Maximizing infiltration will lead to less flooding in parking
lots, roads, and residentials areas which put less strain on sump pumps in residents homes and
underground pipe systems. In some cases, green infrastructure may have a higher initial cost
but the costs over these structures lifetimes will be minimal. Taking that into consideration
along with the ecosystem services gained, it is clear that the benefits of green infrastructure
outweigh the costs of standard gray infrastructure. Since costs are so variable, we recommend
25
that Oshkosh look into the costs of implementing these landscaping techniques while keeping in
mind that these are investments that pay themselves off over time.
Barriers:
When attempting to implement these green infrastructure techniques, various barriers
present themselves. Some of the main barriers include lack of legislative mandates, lack of
funding, lack of effective market incentives, and the overall resistance to change. Some
proposed solutions include using grassroots efforts to garner support for ordinances and
regulations, addressing hurdles in market approaches to provide funding mechanisms, and to
educate and engage the community through demonstrations and events (Roy et. al., 2008).The
use of grassroot efforts to support for ordinances and regulations will help new legal mandates
for stormwater runoff gain popularity. The city of Oshkosh would need widespread public
support to be successful. For example, to gain this support, watershed groups and other
stakeholders can encourage local government agencies to communicate and adopt uniform
watershed regulations and engage the rest of the city to do so as well.
Since stormwater runoff isn't just an issues that the city has to deal with, finding ways to
motivate the public to implement native plants and bioretention within their own property is
another barrier. An incentive approach may be successful but the rebate amount must be high
enough to encourage green infrustruce practices (Roy et. al., 2008). Following up with one of
Margy's concerns, that incentive program/tax credit must be enforceable and less complicated
to avoid issues like the credit for rain barrels in Oshkosh.To avoid some of this confusion, the
26
credit should be connected explicitly with runoff volume from a property to maximize effect. To
relate this to our recommendation, the point system in the city of Oshkosh's landscaping
ordinance can be utilized to increase market incentives to build rain gardens within their
property.
Lastly, to the city of Oshkosh needs to educate the community. To reduce skepticism of
these new best management practices, demonstrations, events, and talks should be conducted
on a regular bases to help the public understand the benefits of bioretention practices and
native plantings as well as give them the knowledge on how to implement them themselves on
their own property.The tools to educate people is already available and on the city of
Oshkosh's stormwater utility section. Already created is a how-to manual for homeowners to
install and maintain rain gardens - it just needs to be utilized to engage citizens. This guide is a
great tool to use to educate residents and should be handed out to homeowners like in our first
case study, Prairie Crossing, Illinois.
There will always be barriers when moving away from the status quo but working to
overcome these barriers is essential to see real change within the quantity and quality of
stormwater runoff. Educating the citizens of Oshkosh is necessary to create public support and
awareness of runoff issues so solutions will be implemented. If all these barriers are properly
addressed, the use of bioretention and native landscaping throughout Oshkosh will greatly
mitigate the stormwater runoff issues we are currently facing.
Significance of Sustainability:
27
Sustainability can be defined as meeting the needs of the present without hindering
future generations ability to meet their needs. Sustainability is made up of three different
pillars: the environmental pillar, the economic pillar, and the social pillar. All of these are
important to consider when proposing actions and they are all things that Oshkosh needs to
analyze before implementing any of the landscaping techniques that we are proposing.
Being environmentally sustainable means conserving the natural environment and the
resources it supplies, while also reducing the negative impacts on ecosystems. When a city is
concerned with being environmentally sustainable, it is conscience of ensuring clean water and
air, reducing pollutants, protecting natural habitats, and using and developing eco-friendly
products for its residents and and society at large. Native plants are an important aspect within
the landscaping features that we recommend the city of Oshkosh implement. The use of native
plants within these features will improve the environmental sustainability in Oshkosh by
increasing the level of biodiversity in the city. Biodiversity is crucial for environmental
sustainability because it creates an ecosystem that is resilient to disease, invasive species, and
other factors that may bring harm to the ecosystem. In addition to the use of native plants,
plants that have deep root systems will also ensure environmental sustainability. Plants with a
deep root system that extends further into the soil than the traditionally used turf grass, provide
more support for the soil. This additional support provided by deep root systems, holds the soil
in place and reduces the amount of erosion that occurs during rain events and from wind and
stormwater runoff. Finally, by implementing these landscaping features throughout the city,
Oshkosh will be increasing the volume of vegetation within the city. This goes a long way in
28
ensuring environmental sustainability because this vegetation will naturally clean the natural
and urban environment of Oshkosh by filtering pollutants out of the air, soil, and water.
In order to be truly sustainable, a city must ensure the health and well-being of its
residents while also ensuring the health of the natural environment . The measures that
Oshkosh would take to improve the health of the natural environment would also go a long way
in improving the human well-being as well. Aside from the potential for pollen allergies amongst
some residents of the city, the implementation of landscaping features will clean the urban
environment and therefore make it healthier for its human inhabitants by reducing the risk of
exposure to contaminants in the air, water, and soil (Hasse et al. 2017). It is also generally
accepted that landscaping features and green infrastructure improve the appearance of cities.
The improvement of human health and the appearance of the city creates an environment that
enables and encourages citizens to be active within their community.
Perhaps the most difficult pillar of sustainability to satisfy is that of the economy. The
economic pillar focuses on the likelihood that practices that are environmentally and socially
sustainable are also going to to be financially feasible now and in the future. This is especially
important when dealing with a limited budget whose allocation is often heavily contested by
competing interests. Although it is presumed that many green infrastructure and landscape
features may be too expensive to implement, it has been shown that the installation of such
features does, in fact, save and make money for those that decide to adopt the practices. An
examination of the gray infrastructure in New York City revealed that the city was likely to save
approximately$1.5 billion from converting cost-ineffective gray infrastructure to green
infrastructure. Complementing cost-effective gray infrastructure (the paved over and cement
29
stormwater management features) with green infrastructure features reduces maintenance
costs and the costs associated with filtering and treating stormwater runoff. Green
infrastructure and landscaping features also encourage new residents to move into an area.
Relating to the social sustainability aspect of improving the appearance of a city, green
infrastructure makes a city more aesthetically pleasing and will draw in more people and
therefore more money for the city (Berkooz 2011). Implementing these ideas will address all
three pillars of sustainability by benefiting the environment, the people, and the economy.
Conclusion:
In conclusion, our recommendation to the City of Oshkosh is to require public and
commercial land to implement green infrastructure and encourage private landowners and
existing structures to do so as well. We want to require all new construction (especially in
parking lots and on main streets) to use rain gardens and bioswales with native plants. Within
Article IX, Section 30-253, item (2) paved areas, we recommend altering the current plan of
requiring 40% shrubbery to specifically requiring 40% native shrubs only. The current plan in
Article IX, Section 30-255, item (3) street frontages, states that the minimum of 50% of all points
are devoted to decorative and medium trees and we recommend changing that to requiring
30% be native trees and a minimum of 30% must be deep rooted native grasses. Native grasses
will filter out pollutants and slow down soil erosion more than trees will. Within Article IX,
Section 30-255, item (2) requirements part (A), our recommendation is to change the current
plan where bioswales and rain gardens get 20 points per 20 square foot area and cannot exceed
30
100 points to assigning bioswales and rain gardens 30 points each without a point limit. We
believe that by not having a point limit and increasing the points bioretention receives, it will
help motivate people to implement rain gardens and bioswales in their own yards as well as in
parking lots and on main streets. We also recommend changes to Section 30-251: Applicability
(B), which would reduce the percentage of expansion of existing buildings that must follow
landscaping requirements. Finally, our recommended changes to Section 30-251: Applicability
(E)-Exemptions, include no longer exempting single family and two family dwellings from
landscaping requirements upon construction of the units.
References:
Aecom. 2012., Soil Mangement plan
Asleson, B. C., Nestingen, R. S., Gulliver, J. S., Hozalski, R. M., & Nieber, J. L. (2009).
Performance assessment of rain gardens.JAWRA Journal of the American Water
Resources Association, 45(4), 1019-1031.
Bartens, J., Day, S. D., Harris,J. R., Dove,J. E., & Wynn, T. M. (2008). Can Urban Tree Roots
Improve Infiltration through Compacted Subsoils for Stormwater Management?Journal
of Environmental Quality, 37(6), 2048-2057.
Berland, A., Shiflett, S., Schuster, W., Garmestani, A., Goddard, H., Hermann, D., & Hopton, M.
(2017)The role of trees in urban stormwater management. (2017). Landscape and
31
Urban Planning., 162, 167.
Berkooz, C. B. (2011). Green Infrastructure Storms Ahead. Planning, 77(3), 19-24.
Buranen, M. (2014, March/April). Developers Go Green for Suburban Stormwater Management.
Storm H2O, 24-35.
Coffman, L. S., Goo, R., & Frederick, R. (1999). Low-Impact Development: An Innovative
Alternative Approach to Stormwater Management. Wrpmd99.
doi:10.1061/40430(1999)118
(n.d.). Retrieved from
https://www.soi ls.org/discover-soils/soils-i n-the-city/green-infrastructure/im portant-terms/r
ai n-gardens-bioswales
Dietz, M. E., & Clausen, J. C. (2006). Saturation to improve pollutant retention in a rain garden.
Environmental science& technology, 40(4), 1335-1340.
Haase, D., Kabisch, S., Haase, A., Andersson, E., Banzhaf, E., Baro, F., Brenck, M., Fischer, L.
K., Frantzeskaki, N., Kabisch, N., Krellenber, K., Kremer, P., Kronenberg, J., Larondelle,
N., Mathey,J., Pauleit, S., Ring, I., Rink, D., Schaarz, N., & Wolff, M. (2017). Greening
cities—To be socially inclusive? About the alleged paradox of society and ecology in
cities. Habitat International, 6441-48.
Hasselkus, E. R. (2012). Guide to Selecting Landscape Plants for Wisconsin. In Master
Gardener(pp. 1-18). Madison, WI: Corporate Extension Publications.
32
Helfand, G., Joon Sik Park,J., & Nassauer, S. The economics of native plants in residential
landscape designs. (2006). Landscape and Urban Planning., 78(3), 229.
Karlenzig, W. (n.d.). What Singapore Can Teach All Cities About Using Urban Green
Infrastructure To Mitigate Megadroughts. Retrieved from
httr)s://www.smartcitiesdive.com ex sustainablecitiescollectivejwill-urban- reen®infrastructure
-hel p-mitigate-megad roughts/1047571/
McLaughlin, J. (2012). NYC bioswales pilot project improves stormwater management. Clear
Waters Volume. 20-23.
Mikkelsen, P. S., Weyer, G., Berry, C., Waldent, Y., Colandini, V., Poulsen, S., D,
Grotehusmann., R. Rohlfing,. (1994). Pollution from urban stormwater infiltration. Water
Science and Technology, 29(1-2), 293-302.
Poe, M. R., LeCompte, J., McLain, R., & Hurley, P. (2014). Urban foraging and the relational
ecologies of belonging.Social& Cultural Geography, 15(8), 901-919.
Roy, A.H., Wenger, S.J., Fletcher, T.D. et al. Environmental Management (2008) 42: 344.
https://doi.org/10.1007/sOO267-008-9119-1
Selbig, W. R., & Balster, N. (2010). Evaluation of turf-grass and prairie-vegetated rain gardens
in a clay and sand soil, Madison, Wisconsin, Water years 2004-08(p. 75). US Department
of the Interior, US Geological Survey.
Yang, H., McCoy, E. L., Grewal, P. S., & Dick, W. A. (2010). Dissolved nutrients and atrazine
removal by column-scale monophasic and biphasic rain garden model systems.
33
Chemosphere, 80(8), 929-934.
What size garden do I need? (n.d.). Retrieved from
httr)://rain.Rardenalliance.orR/riRht/calculator
34