Berwyn Depot District Streetscape IGI Grant Application
MASEFinalReport (2)
1. MASE Consultants
5500 Wabash Avenue
Terre Haute, IN 47803
May 6, 2015
Mr. Reid Cepa
Lochmueller Group
3502 Woodview Trace, Suite 150
Indianapolis, IN 46268
Dear Mr. Cepa:
MASE Consultants is pleased to provide Lochmueller Group and the City of Peru, Indiana with a report of
the final design to reduce combined sewer overflows (CSOs). The attached report includes designs for new
interceptor and conveyance pipes, a system to treat the water for a CSO event, and a roadway design.
If you have any questions or concerns, please do not hesitate to contact Ethan Kroh at krohef@rose-
hulman.edu or 260.388.2788. We would like to thank you for the opportunity to work with you and on
this project.
Sincerely,
Sunil Satish Marlo Niverson
Ethan Kroh Austin Thomas
Cc: Dr. Michael Robinson, Dr. Kevin Sutterer
Attachments: Final Design Report: Peru CSO
Project Manager Project Engineer
Project EngineerClient Liaison/Project Engineer
3. DISCLAIMER
The contents of this engineering design report were prepared by civil engineering students at Rose-
Hulman Institute of Technology for their senior capstone design class. MASE Consultants is a fictitious
company created by these students: Ethan Kroh, Marlo Niverson, Sunil Satish and Austin Thomas for the
purpose of this class. These students are not registered professional engineers. All material presented
herein should be reviewed and stamped by a professional engineer prior to construction. A liability waiver
has been signed by the client, and copies are available from the client and Rose-Hulman Institute of
Technology.
4. Table of Contents
List of Appendices
Appendix A – Desk Studies
Appendix B – Lab Testing
Appendix C – Conceptual Assessment
Appendix D – Geotechnical Design
Appendix E – Watershed Modeling
Appendix F – Transportation Design
Appendix G – Hydrology Design
Appendix H – Environmental Design
Appendix I – Cost Analysis
Appendix J – Sustainability Design
Appendix K – Construction Sequencing
Appendix L – State Revolving Fund Report
Executive Summary 1
1.0 Project Overview 2
2.0 Design Requirements 3
3.0 Client Requests 3
4.0 Constraints 3
5.0 Deliverables 3
6.0 Design Layout 3
7.0 Design Solution 5
8.0 Construction Sequencing 9
9.0 Cost Analysis 9
10.0 References 10
5. 1
Executive Summary
The City of Peru in Indiana is currently experiencing combined sewer overflow (CSO) events that allow
wastewater to discharge directly into the Wabash River. Peru’s Utilities Service Board reports that the
area has experienced an average of 16 CSO events annually. The Environmental Protection Agency (EPA)
allows a maximum of four per year. To meet these standards Lochmueller Group was contracted to
update the piping network, and design a basin and wetland system that will capture and treat the storm
water produced by a 10-year, 1-hour storm. Lochmueller has requested that MASE Consultants perform
a preliminary engineering design to capture and treat these CSO events. MASE has designed a new
piping system, roadway designs and two potential treatment options for excess flow.
Included in this design is a new interceptor and conveyance piping system to capture flow resulting from
the 10-year, 1-hour storm. We simulated the Peru subcatchments in the Environmental Protection
Agency Storm Water Management Model (EPA-SWMM). We calibrated the model using historic inflow
data to the wastewater treatment plant (WWTP) and historic storm data. With this data, we modeled
different historic storm events and calibrated the model to match these events so that we could analyze
the systems response to the design storm. Using this analysis, we determine the new interceptor piping
that would need to be installed along Canal Street, which we will refer to from this point on as the Canal
Street Interceptor.
In order to accommodate for the traffic volumes and the new interceptor sewer being installed under
the roadway, a backfill and pavement design was needed to ensure the roadway was properly
supported and the pipeline was sufficiently protected. Also, to ensure the roadway would not have to be
expanded, a capacity analysis was done based on the traffic on Canal Street. This analysis showed that
one lane is required for each direction of traffic, and specifies the compaction requirements to protect
the piping.
In addition, the new conveyance pipe, the Wabash River Force Main, will run from the Canal Street
Interceptor, under the Wabash River to the WWTP. Our treatment design is a detention basin that will
capture the first flush and a wetland to treat all other excess flow that is diverted away from the WWTP.
6. 2
1.0 Project Overview
This project entails finding a solution for the CSO events for the city of Peru, Indiana, along the North
and South banks of the Wabash River. The Peru Water Management WWTP has a maximum design
capacity of 26 million gallons per day (MGD) of water. According to Peru’s Utilities Service Board, the
area has experienced an average of 16 CSO events annually whereas the EPA allows a maximum of four
per year. These overflows are counted against the city’s permit requirement for waste water treatment
and we have designed a solution to capture, transport and treat these flows. Our client is Lochmueller
Group, an engineering consulting firm in Indianapolis, Indiana. Not only have we worked with them on
a viable design option, but we have worked closely with the city of Peru and have met with several
WWTP employees and managers.
Our design captures the flows generated by a 10-year 1-hour storm, as it was determined and
approved by our client that anything over this amount is considered dilute enough to discharge straight
into the Wabash River. Overall, the site on the north side of the Wabash River has some houses and
businesses along the two and a quarter mile stretch of Canal Street that will be disrupted during the
implementation of the Cana Street Interceptor. On the south side of the river, the site of our detention
design is farmland owned by the city of Peru. The site is relatively flat, with the largest elevation change
of four feet, except along the slopes near a stream running through the site. The stream runs about five
hundred feet to the west of the WWTP. A map of Peru is shown in Figure 1 with the plot of land for our
designs marked.
Figure 1: Project Location and Plot Boundaries. Cited: Google Map
7. 3
2.0 Design Requirements
The Peru CSO project has several significant components needed for the final design. This project
requires an interceptor and conveyance pipe system to collect and transfer the wastewater to the
treatment plant. The next step in the treatment design is a pretreatment basin to hold the water
exceeding the WWTP’s capacity. Following that step in the process, there is also a design needed for a
wetland area and an ultraviolet (UV) treatment system. Along with these elements, a roadway design is
also required for the road under which the Canal Street Interceptor will be installed. There are also
geotechnical design aspects throughout the project including backfill for the Canal Street Interceptor,
collection methods, testing, research, and excavation analyses.
3.0 Client Requests
The main requirement that our client has requested is the design of the collection and treatment
systems. Along with using the Michigan Approach, as provided by our client, for our design storm, our
client’s design priorities key requests are the wetland and the UV system. Our client also requested that
one version of the report be in State Revolving Fund (SRF) format. This is so they can use this version of
the report to apply for the State Revolving Fund Loan to fund the project (State Revolving Fund).
4.0 Constraints
The major constraint is the cost of construction for the system. This is significant as this is a project that
is funded via loans and the tax payers of the City of Peru. Since we were given no price limit,
minimization of the cost was looked at and this affected aspect such as material used and was a major
factor in our comparison of different alternatives. The amount of land available for the pretreatment
basin and the wetland, approximately 580 acres, is also a constraint that influenced this project’s design.
The land that was used for this project is currently owned by the City of Peru.
5.0 Deliverables
MASE consultants has provided a final design for the Canal Street Interceptor and Wabash River Force
Main as well as the pretreatment basin and wetland design with a UV system as the final stage of
treatment. A roadway analysis and design for the reconstruction of Canal Street is also provided. This
report contains all the requested deliverables.
6.0 Design Layout
To accommodate the wastewater flows that Peru is producing, we have designed a multistage process
to convey the expected flows. The Indiana Department of Environmental Management’s (IDEM)
Michigan approach states that the treatment system must be able to properly handle flows that result
from a 10-year 1-hour storm. According to our model, we are expecting a peak system flow of
approximately 138 MGD; the WWTP has a maximum capacity of 26 MGD.
Our design is composed of a detention basin, wetland, and UV disinfection system. In order for the
collection system to convey the expected flows, we designed a new Canal Street Interceptor, the
Wabash River Force Main and a new pump station to send the flow across the river. The need for a new
8. 4
pump station is so the Wabash River Force Main can flow at its peak capacity. Any flow above the
WWTP capacity will be diverted to the detention basin.
The detention basin is designed to store the volume produced by the first flush of the 10-year, 1-hour
storm, which we have calculated to be 2.2 million gallons, but have sized it to hold a max capacity of
2.32 million gallons. Once the detention basin is filled, the remaining flow will bypass the detention
basin and flow through to the wetland. Figures 2 and 3 show the expected process flows during the 10-
year, 1-hour storm for both prior to and immediately after first flush volume being reached. This
wetland has a volume of 2.52 MGD.
The wetland is designed to perform primary treatment but it is also to perform partial secondary
treatment using specialized plant species which are native to Indiana (Native Plants of Indiana). The flow
will travel through the wetland at a flow rate of 1.26 MGD with a retention time of 2 days. This flow rate
will ensure that our wetland will be dewatered in under the 48 hours required by IDEM’s Michigan
approach. The outflow from the wetland will be pumped through the UV system before being
discharged into the Wabash River.
Table 1 illustrates our system. It explains how the system will run during dry weather flow, how it will
run during and after the 10-year 1-hour storm in terms of flow through the system, the emptying of the
detention basin and wetland, and also how it will perform for flows that exceed those expected from
our storm event. The process diagrams for these scenarios can be found in Appendix H.
Figure 2: Flows during at 10 year, 1 hour storm prior to detention basin capacity being reached
9. 5
Figure 3: Flows during a 10 year, 1 hour storm after detention basin reaches capacity
Table 1: System response to certain storm scenarios
Dry weather All wastewater is pumped directly into the treatment plant and is fully
treated there before being discharged into the Wabash River.
First flush for up to a 10-
year, 1-hour storm
All wastewater with flow less than 26 MGD goes into treatment plant and
treated like dry weather. Excess flow is diverted into a detention basin until
the treatment plant can take treat the excess stored wastewater.
Over first flush for up to
a 10-year, 1-hour storm
The process is the same as above, except for the volume over first flush. This
is diverted into a wetland for treatment and then through disinfection
before it is discharged straight into the Wabash River.
Exceedance of 10-year,
1-hour storm event
The same processes as the previous three occur. Excess of a 10-year, 1-hour
storm event will have flow diverted through wetland at a higher rate, since
the combined sewer overflow will be more dilute.
10. 6
7.0 Design Solution
7.1 Hydraulic Design
The SWMM model of the Peru, IN collection system resulted in design solutions for the improvement of
different pipes within the system. The resulting pipe sizes were determined based on this model to
accommodate the increased flow rate (See Table 2). The Canal Street Interceptor size was also
determined using this model (See Table 2).
Table 2: Interceptor conduits and their original diameters and new depths.
Conduit
Original
Diameter (ft)
New
Diameter (ft)
C951 1.25 4
C955 1.25 4.5
C954 1.25 5.5
C956 2 7
C957 2 6
C958 2.25 7.75
C843 2.25 7
C828 2.25 5
C959 1.5 5
C809 1 5
C808 1 5
C987 0.5 6
Force Main 2 4
The design solution for the Cass Street Pump Station was to replace the four original pumps within the
station with four upgraded pumps to handle the new flows through the Wabash River Force Main. The
new pumps within the pump station will be 24” 5731 W, WD Submersible Angleflow Pumps (Fairbanks).
The solution proposed is to close all of the CSO outlets during the installation of new pipes except for
two of the outlets. One of the outlets will be located on the eastern side of the pump station and the
other will be located on the western side of the pump station. The locations of the outlets left open can
be seen Figure 4.
11. 7
Figure 4: CSO outfalls remaining open
7.2. Wastewater Treatment Design
MASE has designed a system to handle flows exceeding the current WWTP’s capacities and to meet the
needs of the city and the standards of the Environmental Protection Agency (EPA). The new treatment
design work (Appendix G) is used to treat flow that exceed the WWTP’s capacity. A detention basin was
designed to not only store the first flush from a 10-year, 1-hour storm, but also to assimilate with the
natural environment of the area. It covers an area of 87,500 square feet and has a maximum capacity of
2.32 million gallons.
Also designed was a wetland system to treat any excess flow beyond the first flush that result from a 10-
year, 1-hour storm event. The wetland will cover an area of 157,500 square feet or 3.6 acres, and will
have a capacity of 2.52 million gallons. The free water surface wetland was designed according to goals
in our sustainability appendix (Appendix J) and will only use native plants of Indiana. This wetland will
also be able to sustain itself well during periods without a major rain event so aquatic vegetation can
thrive since the liner will keep the soil saturated. These will all be connected with a pipe network
consisting of 7 new pipes ranging from 0.5 feet in diameter to 3 foot in diameter (Appendix G).
7.3 Canal Street Roadway Design
To accommodate for the traffic volumes on Canal Street and the Canal Street Interceptor being installed,
a backfill and pavement design was needed to ensure the roadway was properly supported and the
12. 8
pipeline was sufficiently protected. For the pipeline, the native soils below the roadway will be
compacted as specified in Appendix F: Transportation to properly protect the pipe. This compaction is
based on the soils seen under the roadway. For the roadway traffic volume it was determined that a two
inch thick asphalt pavement was required with a four inch sub-base as seen in Figure 5 (Asphalt
Pavement Association of Indiana). To ensure the roadway would not have to be expanded, a capacity
analysis was done using traffic data collected on Canal Street. This analysis showed that one lane is
required for each direction of traffic. For more details on these design aspects, see Appendix F.
14. 10
8.0 Construction Sequencing
Our recommendation for the construction sequencing is a three phased approach. Phase one will
include construction of the pretreatment basin, the wetland, and the UV system south of the Wabash
River. The second phase will include construction for the Canal Street Interceptor and the Wabash River
Force Main. The final phase will include reconstruction of Canal Street and seeding disturbed urban
areas. Using this approach will allow the existing system to function during construction and strives to
minimize disturbance of local businesses and traffic. See Appendix K for a details list of action items.
9.0 Cost Analysis
Included is a cost analysis for the major parts of the project. The first is the Canal Street Interceptor,
which includes the removal of the existing interceptor pipe, excavation, and the installation of the new
pipe. The same aspects were included for the conveyance pipe with the addition of the pumps and the
construction cost of crossing the Wabash River. For the pre-treatment basin, this cost includes all
excavation needed, the construction of the berms, and the disposal of excess materials. The cost
associated with the wetland includes the excavation, construction of the wetland, and the plants within
the wetland. Lastly, the cost associated with the UV system includes the system itself as well as the
piping required for conveyance from the wetland. See Appendix K for a detailed cost analysis.
Table 3: Cost Analysis Summary
Roadway / Interceptor Sewer $3,817,620
Conveyor Pipe $1,674,193
Detention Basin $188,274
Wetland $246,507
UV Disinfection $137,729
New CSO Treatment Pipes $501,207
Grand Total $6,565,528
Peru Scaling Factor 90%
Finalized Total $5,908,975
Project Overview
15. 11
10.0 References
Asphalt Pavement Association of Indiana (APAI). (2009). Guide For Specifying Asphalt Pavements For
Local Governments (Using INDOT Standard Specifications Section 402), Indiana
Fairbanks Nijhuis. (2015). Fairbanks Nijhuis website. http://www.fairbanksnijhuis.com (February 2015).
Google Maps. (2015). [Peru, Indiana] [Google Earth Image]. Retrieved from
http://www.google.com/maps/place/Peru,+IN+46970/@40.74531,-
86.0685181,3421m/data=!3m1!1e3!4m2!3m1!1s0x88146838c6663697:0xae911e4a106d45bd (January
16, 2015)
Native Plants of Indiana. (2009). Indiana University website.
http://www.indiana.edu/~clp/documents/Aquatic_Plant_Materials/Common_Navtive_and_Exotic_Aqu
atic_Plants_IN.pdf (January 16, 2015)
State Revolving Fund. (2015). Indiana Finance Authority website. http://www.in.gov/ifa/srf/ (January 16,
2015)
17. 1
A.1.0. Environmental, Economic, and Social Considerations (EESC)
A.1.1. Background
The plot in question is located in the City of Peru in Miami County Indiana. The plot is located west of
the current WWTP on the south side of the Wabash River. The size of the plot is roughly 100 acres with a
relatively flat topography. The majority of the plot is currently used as farmland with two houses located
right outside of the plot. This plot will be developed to act as a detention basin and a wetland to aid the
nearby WWTP during a rain event.
In evaluating the EESC, we attempted to cover each topic to its fullest extent and attempted to imagine
the project as a whole. We will consider these as we move forward in the project and want to try to
incorporate some best management practices into our final design. Splitting these three categories up
seemed to make the most sense and made it easier to fully examine each.
A.1.2. Economic
One economic factor to consider is the actual price on the final product. The design storm currently is a
10-year 1-hour storm. The WWTP could simply be expanded in order to handle the entire load expected
but this would require large pipes and facilities for the WWTP. It is not feasible to do this which is why
money is an important economic consideration to be aware of. Another economic consideration is the
cost to handle the CSO events that occur. A price comparison will be done between the proposed design
and how much it currently costs to handle the CSOs to make sure that it is worth it in the end to design
an entirely new system. There are not many businesses along Canal Street so closing the road during
construction should not have a large impact on the surrounding community. We will still need to
determine if it is appropriate to hurt these businesses and if any notices or compensation needs to be
given. The other important factor is to make sure the project be formatted to apply for the State Revolving
Fund program.
A.1.3. Environmental
An environmental consideration is the improvement in water quality discharged in the river. Since the
water will travel through a detention basin, wetland, and UV disinfection system, there are many
processes that the water goes through that clean it so the quality of the water discharged and the quality
of the Wabash should see an improvement. A water quality test could be taken to see the extent of the
improvement. There should also be less CSOs occurring which would result in less water running across
the streets and land. This will lead to less erosion of the surroundings and the odor from the waste water
will have a smaller effect and be less noticeable.
A.1.4. Social
A major social consideration is the fire station on Canal Street. Because construction may require tearing
up and closing the road, there still needs to be a route in order for fire trucks to pull out of the station.
Another social consideration is the pride that the community could have by having less CSOs and better
quality water. The staff at the treatment plant is already proud of the treatment processes and the plant
and I am sure both them and the local community would have more pride if there was a higher quality
18. 2
water being discharged which would lead to things such as less odor. It could also lead to possibilities such
as new businesses such as recreational activity in the water or perhaps community events celebrating the
treatment plant as well as the quality of the water and unique processes it goes through.
A.2.0. Preliminary Feasibility Study
A.2.1. Background
The plot in question is located in the City of Peru in Miami County, Indiana. The plot is located west of the
current WWTP on the south side of the Wabash River. The size of the plot is roughly 100 acres with a
relatively flat topography. The majority of the plot is currently used as farmland with two houses located
right outside of the plot. This plot will be developed to act as a detention basin and a wetland to aid the
nearby WWTP during a rain event.
A.2.2. Overview
Peru Operations is the utilities provider for the city of Peru, Indiana. It serves approximately 4,482
customers with a sewer system that contain 85 miles of piping. The activated sludge WWTP plant of Peru,
Indiana has a rated maximum capacity of eight million gallons per day with a peak of twenty-six million
gallons per day.
The water treatment and distribution aspect of Peru Operations serves 4,800 customers with raw water
obtained from Teays River Aquifer and 4 wells that have the maximum capacity of 9.5 million gallons per
day. This treatment plant has a storage capacity of 3.35 million gallons.
A.2.3. Legal
The south side of the Wabash is located in a floodplain area (Figure A.1 below). Chapter 155.22 of the
Peru, Indiana Code of Ordinances states the duties and responsibilities of the floodplain administrator.
These responsibilities consist of reviewing the floodplain development permits, ensuring that the
construction has been authorized by DNR. Adjacent communities and the Sate Floodplain Coordinator
must be notified before any alteration or relocation of a watercourse is made. Maintenance of the altered
area is required to ensure the flood-carrying capacity is not damaged. Verification must be made of the
actual elevation of the lowest floor of the new structures as well as the actual elevation to which any new
structures have been flood proofed.
19. 3
A.2.4. Zoning
The zone that the new development area falls under is (K) FP Flood Plain, (L) FF Flood Fringe and (C) A-3
Agriculture. The Flood Plain area consists of areas that are outside the floodways that have the propensity
of causing damage due to the high water. While identified as zone (K) in the Peru, Indiana’s Code of
Ordinances, this area is designated as Zone A on flood hazard zone maps. The Flood Fringe area is outside
of the floodway that could be damaged by high water. This area is designated as Zone X on the flood plain
map. If a structure is built in this area, the first floor must be two feet above the flood hazard area. The
part of the site that can be classified as A-3 Agriculture is where the storage basin will be built. The district
is classified as rough farmland with overgrowth, wetlands and wooded area with moderate slope. There
are no wetlands located on the site currently. The constructed wetland will be placed on the site located
to the south of the Wabash River.
The site consists of two sites separated by the Wabash River with public roads running near or right on
top of the sites. The interceptor side of the Wabash runs alongside public road Canal Street. This road
will be directly affected when construction to install the interceptor pipe commences. The Waste Water
Treatment side of the Wabash is separated from the Wabash by Riverside Drive. There is also a private
property located on the south side of the site that will need to be considered.
20. 4
A.2.5. Utilities Under Site
When constructing the detention basin and the wetlands, the location of the utilities underground must
be considered. While the land is mostly undeveloped, making the chance of unknown utilities present
underground very small, there is a plot of land with two houses that could create reason for concern.
Fortunately, the homes are abandoned and have been purchased by the city, meaning utility locating will
be fairly simple.
With the designing of a pipeline, a detention basin, and a constructed wetland, knowledge of the grade
of the land will be a very important item to have. Our client, Lochmueller Group has been contracted by
the city of Peru, resulting in receivables that will include a topographical map of the site.
A.3.0. Phase 1 ESA
A.3.1. Background
The plot in question is located in the City of Peru in Miami County, Indiana. The plot is located west of the
current WWTP on the south side of the Wabash River. The size of the plot is roughly 100 acres with a
relatively flat topography. The majority of the plot is currently used as farmland with two houses located
right outside of the plot. This plot will be developed to act as a detention basin and a wetland to aid the
nearby WWTP during a rain event.
A.3.2. Hazardous Materials
Our company has looked for potential risks on this site and surrounding area or potential construction
zones and has located two potential issues. The primary concern is the north side of the Wabash River
and south of Canal Street. The second issue is located to the west of WWTP in the area that is farmlands.
The area north of the river is a gradual slope down towards the river and seems to be relatively unused
currently. Our concern with this area is that we were told by our client that this may have been a
hazardous material dumps site in the past as shown in the map shaded with red diagonal lines (Figure A.2
below). This would create issues during excavation for our new interceptor sewer as we went to pump
the flow across the river to the treatment facility with worker and public health concerns as well as the
river washing loose soil downstream after we disrupt it.
21. 5
Also, another area of concern would be chemicals used on the farmlands, shaded in light green (Figure
A.3 below), where the proposed wetland will be going. This land is up to 50% crop use based on the image.
Looking into zoning records for Peru, these farms have been in the area since around the latest records
that were available dating 1923. This would mean that chemicals like herbicides and pesticides have been
soaked into the soil for a long period of time. Although the wetland will help mitigate the adverse effects
of these chemicals used during plant treatment, we may need to check how concentrated the residual
chemicals are there, and if we need to do special planning for the area to ensure work and public safety.
These are the main areas of concern we have after our initial desk study, but more issues may come to
fruition after visiting the site. These issues need to also be examined closely during the site visit to figure
out the validity and feasibility of handling these issues.
22. 6
A.4.0. Geology
A.4.1. Background
The plot in question is located in the City of Peru in Miami County, Indiana. The plot is located west of the
current WWTP on the south side of the Wabash River. The size of the plot is roughly 100 acres with a
relatively flat topography. The majority of the plot is currently used for farm ground with two houses
located right outside of the plot. This plot will be developed to act as a detention basin and a wetland to
aid the nearby WWTP during a rain event.
A.4.2. Tectonics
Based on the Indiana Geological Survey (IGS) website, there are a few tectonic features for the Northeast
Indiana area. There are two fault lines notably close to the plot site. To the Northwest lies the Royal Center
Fault, and to the South lies the Fortville Fault. Even with these fault lines near the plot however, there
does not seem to be any significant effects on the area because these faults are considered inactive.
According the USGS seismic map, the area where the plot lies is classified as a zone 1 seismic area. This
indicates that seismic events are relatively rare and tend to be mild in nature.
A.4.3. Geological
According to the IGS, the following information is a prediction of what one would expect to see in this
area. The bedrock layers of this area are classified as a Silurian bedrock with the possibility of seeing some
Ordovician bedrock in the Northeast corner of Miami County. Silurian bedrock is classified as containing
23. 7
the following bedrocks: dolostone, limestone, siltstone, and shale. In this list, dolostone is the deepest
layer and shale would be the shallowest. For this preliminary study, no cross section specific site data was
available for this area.
A.4.4. Geomorphological
Based on the information found in the USGS database, there are a few possibilities as to what
geomorphology one would see on this plot. The most probable possibility would be a silty clay loam or a
clay loam till of the Lagro formation. This specific area is also said to have morainal topography, meaning
there could be some random materials such as boulders, gravels, and sands left by a glacier. Along the
Wabash River, there are veins of alluvium due to the presence of the moving water. Alluvium is known to
have light silts, sands, and gravel mixed and is common around streams and rivers. There is also a slight
chance of other materials being present such as loam till and undifferentiated outwash. These types of
materials could be present due to the Wabash River or leftovers from a glacier.
24. 8
A.5 References
City of Peru, Indiana Code of Ordinances. (2012). “Duties and responsibilities of the floodplain
administrator” Chapter 155.22: Flood Hazard Areas, Cincinnati, OH
City of Peru, Indiana Code of Ordinances. (2002). “Establishment of city zoning districts” Chapter
151.040: Zoning Code, Cincinnati, OH
Google Earth/Maps. (2014). [Peru WTTP, Peru, IN] [Street Map] Retrieved from <
https://www.google.com/maps/place/Peru,+IN+46970/@40.7499157,-
86.0675614,14z/data=!4m2!3m1!1s0x88146838c6663697:0xae911e4a106d45bd> (09/20/2014)
Indiana Geological Survey (IGS). (2014). Indiana Maps. < http://maps.indiana.edu/> (09/20/2014)
Peru Utilities Service Board. (2014, October 1). Board Meeting.
<http://www.peruutilities.com/bm20141001.htm>
National Oceanic and Atmospheric Administration (NOAA). (2014). Hydrometeorological Design Studies
Center. <http://hdsc.nws.noaa.gov/> (October, 2014).
United States Geological Survey (USGS). (2014). < http://www.usgs.gov/> (09/20/2014)
26. 1
B.1.0. Field Work
B.1.1. Penetration Testing
We conducted the dynamic cone penetration tests at four different points throughout our proposed
jobsite. The procedure followed can be found in Manual 7 for the Wildcat Dynamic Cone Penetrometer
(Drafted Feb. 23, 2000). The only variance from this procedure was the rods were never perfectly
perpendicular to the ground and would tend to be driven at a slight angle. The four points that were
chosen around the jobsite have the potential to have significant development in that area based on the
design work requested from the client. The first point chosen lies on the east side of the plot,
approximately 200 yards from the waste water treatment plant’s fence. This point was chosen because
this is a potential site for the detention basin requested. The second point was taken on the other side
of the drainage ditch that essentially cuts the jobsite in half. This point was significant due to the
drainage ditch dividing the plot and this is located in a separate piece of farm ground compared to point
one. The third and fourth points were recorded along the western property line of the land owned by
the city. The third point is in the southern half of the plot and the fourth is on the northern half, closer
to the West Riverside Road. These points were deemed necessary because this area has the potential to
be developed into the requested wetland. The exact location of these four points was recorded via GPS
as well. For the data collected, see attached Tables B.1-4 for the penetration test data and GPS locations
Figure B.1. The figure is also shown below.
27. 2
Figure B.1: Penetration Test/Soil Sample Sites
B.1.2. Soil Samples
In order to procure samples for soil testing, tube samples as well as bulk samples were taken from three
points throughout the site as well as only a bulk sample taken at a fourth point. The soil was accessed
using a fence post shovel. Using a drop hammer to drive the muffler tubes, the soil was sampled
approximately two feet below ground surface. Once the muffler tube sample was collected, a shovel-
full was collected for a bulk sample.
28. 3
B.1.3. Traffic Data
A major aspect of the Peru CSO project is installing an interceptor pipe below one of the main streets of
Peru (Canal Street). In order to have an idea of the traffic volume and possible disturbance, a traffic
count was procured on Friday, October 10, 2014 from 3:04p.m to 3:34p.m at the intersection of Miami
Street and Canal Street. Miami Street is oriented in the northern and southern directions and Canal
Street is oriented in the eastern and western directions. Because the Wabash River runs along the
southern side of Canal Street, Miami Street does not have a southern direction, causing the intersection
to be a T-intersection. The T-intersection does not impair any of the data as all of the intersections along
Canal Street have the same layout. See Table B.5 for a tabulated summary of the traffic count.
Table B.1: Penetration Testing
32. 7
Table B.5: Traffic Counts
B.2 Lab Work
Unconfined Compression
We conducted the Unconfined Compression test based on the ASTM D 2166. One deviation we
experienced was the samples were taken using a makeshift sampling tube provided by Rose-Hulman
versus using a Shelby tube. Another deviation from the process we encountered was a defect in one of
the tubes. The tube for sample location #3 had a dent around the rim. This caused a cavity along this
edge of the sampled specimen. We accounted for this in our density and volume by subtracting the
estimated area of this gap from the cross-sectional area. This allowed us to still collect data from this
sample despite the appearance of it. The sample obtained from location #4 was deemed unusable due
to a dent around the rim of this sampling tube which compacted the soil to create an inaccurate
interpretation of the soils density. For the data collected and the results from the testing, see attached
Figures B.2-4 for the Unconfined Compression testing.
33. 8
Hydrometer Testing and Sieve Analysis
After separating the soil samples, following the procedures outlined in ASTM D 421, we used
approximately 115 grams of each soil to perform a hydrometer analysis. 15 grams of each sample was
taken aside to find hygroscopic moisture content. The rest was used in the hydrometer testing and
afterwards for the sieve analysis, following ASTM D 422. All of the samples lost a large amount of mass
after rinsing through the #200 sieve and the results of the hydrometer analysis also reaffirms that a
large portion of the soil, from each location, is silt material with a large percentage of fines. The
moisture contents also averaged around 2.45%. This could be due to the migration of silt particles and
the percentage of fines could be explained by the wear the silt endures as it is tilled at least every 6
months due to the fact that the land is used as farmland. For the hydrometer graphs, see attached
Figures B.5-8.
Atterberg Limits
We conducted Atterberg Limits testing for the four soil samples in accordance with ASTM 4318. Each
member conducted testing on one of the samples to complete this portion of soil analysis. Our data
seemed to come out with reasonable results with just a couple of noticeable differences. The most
evident variance was that our soil from Location #4 had a higher liquid limit than the other three
locations. This is most likely because this point was the closest to the Wabash so it may have had some
effect on the soil in that area. The other distinct difference was that the plastic limit for the soil sample
from Location #1 had a much lower plastic limit than all the other samples. This point was the closest to
the wastewater treatment plant, so that may be some reasoning for this value or it may have been from
bad testing results. Overall, this test showed us that our soil has either no plasticity or slight plasticity,
which would indicate we most likely do not have very much clay, but large deposits of silt in the areas
we took our soil samples. The data collected can be seen in Figures B.9-12.
42. 17
B.3 References
American Society for Testing and Materials (ASTM). (1998). “Standard Practice for dry preparation of soil
samples for particle-size analysis and determination of soil constants.” D421-85, West Conshohocken,
PA
American Society for Testing and Materials (ASTM). (2000). “Standard test methods for liquid limit,
plastic limit, and plasticity index of soils.” D4318-00, West Conshohocken, PA
American Society for Testing and Materials (ASTM). (2002). “Standard test method for particle-size
analysis of soils.” D422-63, West Conshohocken, PA
American Society for Testing and Materials (ASTM). (2000). “Standard test method for unconfined
compressive strength of cohesive soil.” D216-00, West Conshohocken, PA
44. 1
C.1.0. Decision Matrix General
1. The higher the score for each option, the more practical the solution is for our project.
2. The weighting system is based on the needs and funding of this project as well as who will
benefit and be served. The higher the weighting, the more important the criteria.
C.2.0. Decision Matrix: Storage
C.2.1. Options:
i. Detention Basin
This option will use the farmland adjacent to the Peru WWTP to create a detention basin
that will hold the specified design storm.
ii. Larger Piping System:
A larger piping system option will not only act as conveyance for the collected storm water,
but it will also be large enough to act as storage once the WWTP has reached capacity.
iii. Larger WWTP:
A renovation of the current Peru Waste Water Treatment Plant would entail increasing the
capacity of the plant to accommodate for the specified storm past the plants current capacity.
C.2.2. Criteria
Costs: The costs analysis done for the storage decision matrix is based on the unit costs found for
installation of the design options mentioned
Detention Basin: Based on attached Calculations and estimations:
30 acres @ 12 ft of depth @ $35/per cubic meter of storage area.
Cost: $15,600,000
Larger Piping System: See Attached Costs for In-system Storage Unit
Cost: $20,330,000
Larger WWTP: See attached costs analysis and sources
Cost: $34,000,000
Space Occupied: The space occupied entails the area that will be used once the system is
installed. The smaller areas score the highest.
Detention Basin: See attached Calculations: 30 acres of undeveloped farm area
Larger Piping System: 1.1 linear miles of existing roadway; underground.
Larger WWTP: Estimated additional area needed 20 acres
Disturbance: The disturbance criteria addresses the area of disturbance during construction based on
the location of the system and what inconveniences it would impose on the public.
Detention Basin: 30 acres on undeveloped farmland with no interaction with property used by
the general public.
Larger Piping System: 1.1 linear miles, will require closer of Canal Street for a significant time.
Larger WWTP: 20 acre expansion onto undeveloped farmland.
45. 2
Operation/Maintenance: This criteria is based on the costs to operate and maintain the chosen design
options.
Detention Basin: A detention basin requires minimal cost to maintain given the
installation was done properly in terms of effective earthwork.
Larger Piping System: These systems require access point as they are underground and also
require specific monitoring
Larger WWTP: A larger plant would imply more costs to the city to run the plant in terms
of electrical and man power.
C.3.0. Decision Matrix: Treatment
C.3.1. Options
UV: Ultraviolet radiation is the process of passing a film of waste water near a UV lamp source
Chlorination: Uses either a gaseous form of CL2 or a hypochlorite slat to produce HOCL with water to
remove contaminants.
Ozonation: Uses the formation of free radicals as oxidizing agents to treat wastewater
Microfiltration: Waste water passes through membrane fibers (hollow cylinders permeated with millions
of microscopic pores)
Detention Lagoon: allows natural disinfection to take place via sunlight and natural microbial die-off.
C.3.2. Criteria
These criteria were evaluated by a study done by the EPA and then applied/ranked based on the needs
for our jobsite.
Effectiveness: Treatment of potentially harmful substances
Cost: Price of installation
Safety Risks: Consequences of failure of the system based on research found
Flow Rates: How much inflow the system can effectively treat
Reliability: How often the system breaks down or needs to be repair based on research
Maintenance: Costs associated with operating and upkeep of the system
Energy Costs: Energy consumed to effectively treat the inflow seen by the system
Building Needed: If a housing unit is necessary to shield the system from the elements. This was
scored as a 1 or 0, 1 being no building is required and would imply lower install and
maintenance costs.
48. 2
Appendix D: Geotechnical
D. 1.0. Introduction:
The Geotechnical aspects of the Peru Combined Sewer Overflow project were evaluated to create a
basic cut fill analysis for the area where the project’s detention basin will be located. MASE Consultants
provides a design and a description of this design in the following sections.
D. 2.0. Project Description:
The Peru Combined Sewer Overflow project is located in the southern part of the City of Peru Indiana on
both the North and South sides of the Wabash River. The objective of this project it to minimize the
number of overflow events that occur in a year. To accomplish this, MASE Consultants have designed a
new collection system of interceptor and conveyance pipes as well as a pretreatment basin. These
aspects will collect and treat enough water to withstand a one-hour ten-year storm. The transportation
design and aspects are along Canal Street. These roads will require new subsurface and paving as they
will be removed to install the new interceptor pipe and conveyance pipe system for the CSO renovation.
D. 3.0. Pre-Development Conditions:
The project site for the Peru CSO involves both undeveloped and developed areas of land. On the north
side of the Wabash River, there is the downtown area of the City of Peru where the piping system will
be collecting the wastewater. This area has been developed and there is significant infrastructure in this
area of the site. South of the Wabash, adjacent to the existing wastewater treatment plant there is a
farm field. This area is relatively level and is clear of any infrastructure. The areas where this project will
be implemented are currently owned by the City of Peru.
D. 4.0. Geotechnical Aspects:
The primary geotechnical aspects that were used in this analysis were done during the field
investigations and the lab work. This allowed us to sample and calculate properties and characteristics
of the soils seen on the project site. These finding and processes are outlined in Appendix B of this
report. These results were then interpreted to perform the cut/fill analysis of this appendix.
D. 5.0. Geotechnical Design Approach:
D. 5.1. Detention Basin Embankment Design.
There were two sources used to provide information on the types of soils in the area. The first being our
physical sample that we collected during our site visit. The second being the “Soil Survey of Miami
County” (USDA:NRCS, 1979).
Referring to the Soil Survey, the soil types seen in the detention basin area are Ross loam and Gessie silt
loam. See attached analysis sheet for description of these soil types and their properties. For our
physical sample data and properties, refer to Appendix B: Lab Testing.
The size of the designed detention basin is 350 feet by 250 feet. The berms of the basin are sloped using
a three to one slope on the inside of the basin and a three to one on the outside of the basin as this is
49. 3
common practice for these types of earthen structures. A cut/full analysis was conducted to see what
materials will be available to build the embankments and whether importing or exporting materials will
be required. This analysis takes into account the shrinkage of soils due to the excavation process during
construction. Considering these factors will ensure the embankments will be at the proper height for the
entrapment of the proper depth of water including a free board height. The cut/fill analysis was
conducted by hand to get an estimate of the volume and scope of the earth work this aspect will entail.
In doing this, the average elevation of the existing area was used as the new ground elevation for the
detention basin.
Based on the cut/fill analysis conducted, there will be approximately 1250 cubic yards of extra material
from the excavation/construction. This excess material can be used to build up the wetland area to
avoid importing soils. See page three for these calculations.
The liner for the detention basin has been designed to prevent any leakage or inflow from the
surrounding landscape and nearby river. With portions of the detention basin being within a flood plain,
this posed added variables to the liner and design of the basin. The liner will require a bottom layer of
high density polyethylene liner (HDPE). This will act as a barrier used to protect the surrounding areas
from the wastewater held in the detention basin. The standard thickness for these types of liners is
approximately 60 mils. The intermediate layer of the basin’s cross section is a geotextile layer. The
geotextile membrane is specified as a GW8 (GSE). This is appropriate base on the capacity requirements
of the basin. The top layer of the designed detention basin cross-section is a 6 inch layer of native soils
on top of the geotextile membrane. This material can be obtained from the excess material from the
initial excavation of the basin. This layer will be used to grow grass on. By growing grass on top of the
liner, this will protect the liner when the basin is empty or not completely full of water while holding the
native soil in place when the basin is full. Originally a clay liner was proposed, but the proposed site has
and insignificant amount of clay within the soils. This would create a great expense to import clay
materials due to the volume needed and the availability of materials.
For the design of the wetland there is an identical basin used as an equalization basin. The same cut/fill
analysis applies for this basin. This will also provide some excess materials which can also be used to
build up the wetland area.
50. 4
Fill Material
Outside Slope Top of the Berm Inside Slope Above Grade
Base (FT) 15 Width (FT) 10 Base (FT) 15
Height (FT) 5 Height (FT) 5 Height (FT) 5
Linear Footage (FT) 1140 Linear Footage (FT) 1040 Linear Footage (FT) 940
Cross Sectional Area (SF) 37.5 Cross Sectional Area (SF) 50 Cross Sectional Area (SF) 37.5
Total Volume (CF) 42750 Total Volume (CF) 52000 Total Volume (CF) 35250
Total Volume (CY) 1583 Total Volume (CY) 1926 Total Volume (CY) 1306
Cut Material
Inside Slope Below Grade Basin Bottom Below Grade
Base (FT) 12 Surface Area (SF) 35916
Height (FT) 4 Depth to Bottom (FT) 4
Linear Footage (FT) 832 Total Volume (CF) 143664
Cross Sectional Area (SF) 24 Total Volume (CY) 5321
Total Volume (CF) 19968
Total Volume (CY) 740
Overlaying Soils
Total Cut (CY) 6060 Thickness (IN) 6 Volume of Overlay 471
Total Fill (CY) 4815 Width (FT) 28.5
Net Cut (CY) 1246 Linear Footage (FT) 892
**Assumption: New proposed grade for the ground level is the average elevation seen on the topographic maps.
This should provide a sufficient rough estimate for this cut/fill analysis, but use of more accurate topographic data
and calculations is recommended for an official cut/fill quantity.
Detention Basin Cut/Fill Model
51. 5
D. 6.0. Resources:
Geosynthetic Lining Systems (GSE) Environmental. (2015). Geotextile Products page.
http://www.gseworld.com/Products/Geotextiles/Environmental-Nonwoven/
The United States Department of Agriculture Soil Conservation Service (USDA: NRCS). (1979). “Soil
Survey of Miami County, IN”.
57. Table of Contents
E.1 Introduction ......................................................................................................................................2
E.2 Project Description............................................................................................................................2
E.3 Current Conditions............................................................................................................................3
E.4 Design Concepts................................................................................................................................5
E.5 Modeling Approach...........................................................................................................................5
E.5.1 Subcatchment Parameters........................................................................................................6
E.5.4 Rain Gage Input Values...........................................................................................................10
E.5.5 Outputs from SWMM Model..................................................................................................13
E.6 Results Summary.............................................................................................................................28
E.1 Introduction
The work detailed in this appendix describes the efforts of MASE Consultants Co. to produce a hydraulic
model to analyze the combined sewer overflow (CSO) events of Peru, IN, the current capacity of the
combined sewer system, and design a new interceptor pipe and conveyance pipe as well as upgrade the
pump station.
The hydraulic model described in this appendix is the main analysis tool used in this portion of the
project. The first objective in using this model is to identify the extent of the CSO events being produced
in the existing system. The second objective in using this model is to build a better system that can
effectively convey of the 10-year, 1-hour design storm.
E.2 Project Description
The city of Peru, Indiana still has a combined sewer network which experiences around 26 CSO events
annually. Due to standards by the Environmental Protection Agency (EPA), the system is now obsolete
and needs to be improved to reduce the number of CSO events. This project will be funded through the
State Revolving Fund and must comply with EPA design standards.
The City of Peru has hired Lochmueller Group to design a solution to reduce the number of annual CSO
events and Lochmueller has subcontracted MASE Consulting to complete the analysis and design work,
as well as prepare a plan for the means and method for construction and traffic control. This appendix
provides the analysis of the watershed and will provide Peru with data necessary to complete the design
work associated with out proposed alternatives as well as prepare for future improvements.
58. E.3 Current Conditions
The City of Peru consists largely of residential neighborhoods, commercial zones, and a small amount of
open grass. The sewer system is comprised of 11 main lines that join together at an interceptor sewer
running along Canal Street. There is a pump station located on Cast Street which pumps the combined
sewage to the waste water treatment plant (WWTP). The WWTP can handle flows up to 26 million
gallons per day (MGD) while the pump station is only able to pump flow across at a max capacity of 19.6
MGD currently. The interceptor sewers upstream of the pump station are undersized though, so the
maximum flow rate at the pump station was 14 MGD. This, in combination with the fact that 26 MGD is
not enough to handle a 10-year 1-hour storm, which is specified by IDEM, causes flow from storm
events to become backed up in the sewer system and rerouted to CSO outlets to be discharged to the
Wabash River. The watershed analyzed only consists of the areas that contribute flow to the WWTP (See
Figure E.1). The land is relatively flat in Peru, with slopes varying from 0.6% to 2%. The highest elevation
is at 700ft while the lowest elevation is at an elevation of 635ft. The land has a general pattern of
sloping towards the Wabash River. The soil is composed primarily of loam and is moderately well
drained (National Resources Conservation Service Web Soil Survey).
60. E.4 Design Concepts
To handle the CSO events occurring in Peru, MASE Consulting has proposed a multi-part solution. One
part of the solution is to resize the interceptor sewers so that the pump station can achieve a pump rate
without causing backflow through the conveyor pipe. The other aspects are a detention basin to collect
the first flush from the 10-year 1-hour storm, wetland, and UV disinfection for flows bypassing the
detention basin to pass through to ensure that they receive primary treatment before being discharged
into the Wabash River. These solutions will cause the WWTP to operate at max capacity while reducing
the total number of CSO events that occur.
All of these components are to ensure that the water is treated to primary treatment level instead of
being directly discharged through a CSO outfall. The detention basin will hold water and eventually
pump it back thorough the WWTP, and when the rainfall volume exceeds the volume of the basin, the
flow is bypassed through to the wetland for primary treatment as well as some secondary treatment,
followed by a UV disinfection system.
To design these solutions, we used EPA-SWMM to model the sewer system of the city of Peru. We chose
this model as it was designed by the EPA and it also allows us to model overland flow and pipe flow
which is important as the sewer system is large and complex. Using the model, we are able to obtain
flow rates which are needed to design the interceptor sewer, wetland, and a UV disinfection system as
well as runoff volume which is needed to design the detention basin.
E.5 Modeling Approach
As the system is comprised of multiple subcatchments and a large, complex pipe network, we created a
model in EPA-SWMM to compute reliable results. We wanted to not only find the total volumes and
flows; we wanted to know which subcatchments contributed and how much they contributed to these
values. We had to make sure that we did not use an over-simplified approach at the same time as well.
Our design required that we obtain the maximum flow rate and total volume resulting from a 10-year 1-
hour storm. EPA-SWMM allows us to model our system through the use of subcatchments, nodes,
conduits, pumps, outfalls, and many other components if needed. We found multiple parameters for
these subsystems and this required research on the composition on the land, the elevations of the pipe
inlets, slopes of the land and conduits, finding the pump curves, and estimations. We focused on
sections that contributed flow to the WWTP as we were given historic flow data to the plant to calibrate
our model. Tables in the back of the EPA-SWMM user manual were used to find acceptable values for
parameters such as Manning’s n and depression storage depth, while other values were used as
calibration parameters such as the subcatchment width and the percent of impervious land, in order to
change the output values we were producing for volume of flow and the peak flow rate. After calibrating
our model to multiple storm events, we ran a 10-year 1-hour storm in order to view the results and use
these output values for our design components. Our final model used is shown below in Figure E.2.
61. Figure E.2: Final SWMM Model – CSOs eliminated
E.5.1 Subcatchment Parameters
The watershed was delineated into subcatchments that provide flow to the WWTP. Our model was
comprised of 12 subbasins that were each individually calibrated in order to match historic storm data.
Our calibration involved adjusting the values of parameters for subcatchments such as their curve
number, areas, and overland flow width. We used historic storms and the volumes of flow produced by
62. them to make sure the model accurately simulated these events. In Appendix G, further detail in
calibrating the model is presented. See Table E.1-3 below for final calibrated values.
Table E.1
Subcatchment Parameters
Subcatchment
1
Subcatchment
2
Subcatchment
3
Subcatchment
4
Area (ac) 30 70 70 40
Width (ft) 4400 6100 2400 4800
Slope (%) 1 0.5 0.6 1
Imperviousness (%) 5 5 5 5
Mannings N (impervious) 0.015 0.015 0.015 0.015
Mannings N (pervious) 0.1 0.2 0.2 0.2
Depression Storage (Impervious) 0.05 0.1 0.1 0.05
Depression Storage (Pervious) 0.1 0.1 0.1 0.1
%Impervious Area with no depression storage 25 10 25 25
Curve Number 75 75 78 80
Table E.2
Subcatchment Parameters
Subcatchment
5
Subcatchment
6
Subcatchment
7
Subcatchment
8
Area (ac) 130 40 45 130
Width (ft) 6900 4300 4000 4300
Slope (%) 0.3 0.6 0.5 0.2
Imperviousness (%) 5 10 10 5
Mannings N (impervious) 0.015 0.015 0.015 0.015
Mannings N (pervious) 0.25 0.2 0.2 0.2
Depression Storage (Impervious) 0.1 0.05 0.05 0.1
Depression Storage (Pervious) 0.1 0.1 0.1 0.1
%Impervious Area with no depression storage 25 5 25 25
Curve Number 85 95 85 90
65. Time (H:M) Value
2:20 0.006
2:25 0.006
2:30 0.006
2:35 0.006
2:40 0.006
2:45 0.006
2:50 0.006
2:55 0.006
3:00 0.006
3:01 0
E.5.4 Rain Gage Input Values
Rain gages in EPA-SWMM are used to create storm hyetographs for subcatchments. Lochmueller Group
and Strands Associates provided us with data from historic storm events to calibrate our model with,
and we developed these storms into SWMM in order to make sure our results were accurate. The
storms used for calibration as well as our 10-year 1-hour storm design are seen in Figures E.4-7. The 10-
year 1-hour storm was designed using data from the National Oceanic and Atmospheric Administrations’
(NOAA) Precipitation Frequency Data Server.
Figure E.4: 10-year 4-Hour storm provided by Strands Associates
Time (H:M) Value
0:04 0
0:05 0.006
0:10 0.006
0:15 0.006
0:20 0.006
0:25 0.006
0:30 0.006
0:35 0.006
0:40 0.006
0:45 0.006
0:50 0.006
0:55 0.006
1:00 0.006
1:05 0.006
Time (H:M) Value
1:10 0.006
1:15 0.006
1:20 0.006
1:25 0.006
1:30 0.006
1:35 0.006
1:40 0.006
1:45 0.006
1:50 0.006
1:55 0.006
2:00 0.006
2:05 0.006
2:10 0.006
2:15 0.006
66. Figure E.5: Storm event on April 25th
, 2014 provided by Lochmueller Group
Figure E.6: Storm event on August 31st
, 2013 provided by Lochmueller Group
68. Figure E.7: 10-year 1-Hour Storm developed with NOAA Data
E.5.5 Outputs from SWMM Model
After calibrating our model and ensuring our results had an acceptable level of accuracy we ran the
simulation using our 10-year 1-hour storm and obtained the results shown in Figures E.8-E.21. The first
model, Figure E.19, includes the CSO outfalls existing. The final model used has the CSO outfalls
removed, but in reality two or three CSOs will be left open in order to allow storms greater than the 10-
year 1-hour storm to be handled by the system.
One thing to note is that the peak at the conveyor pipe was only around 15 MGD, the peak above this is
assumed as an error in estimation of the storm. This along with the fact that multiple nodes along the
interceptor sewer are flooding reconfirms that the interceptor pipe is undersized. The output values for
the historic storm in the model accurately match the volumes of flow that were measured so this leads
us to believe that our hydrologic model is simulating the real world conditions accurately. Also shown
are the runoff data from each individual subbasin as well as the flow through the interceptor sewer.
Another important output given by the model is the total flow going into the WWTP. The plant has a
maximum design capacity of 26 MGD but the inflow graph below shows that it is only operating at
around 21 MGD. This results in flow being released at CSO outfalls which, if the plant operated at peak
efficiency, could be reduced.
83. Figure E.21: Inflow into WWTP for 10-year 4-Hour Storm
E.6 Results Summary
The output data from SWMM shows us the flows that currently exist in the pipe network of Peru. There
are multiple million gallons of flow being discharged during storm events which could be reduced greatly
if the conveyor pipe and WWTP were both operating at maximum capacity. In order to handle the 10-
year 1-hour storm, the interceptor sewer and conveyor pipe will need to be resized, a new pump will be
needed to pump the water across the river, and the pipe network needs to be analyzed without the CSO
outfalls. The Hydrology appendix details the approach and results for the new system that is able to
handle the 10-year 1-hour storm.
85. 1
F. 1.0. Introduction
The transportation aspects of the Peru Combined Sewer Overflow project were designed to maintain
the current roadway conditions and uses. MASE Consultants provides a design and a description of this
design in the following sections.
F. 2.0. Project Description
The Peru Combined Sewer Overflow project is located in the southern part of the city of Peru, Indiana
on both the north and south sides of the Wabash River. The objective of this project is to minimize the
number of overflow events that occur in a year. To accomplish this, MASE Consultants have designed a
new collection system of interceptor and conveyance pipes as well as a pretreatment basin. These
aspects will collect and treat enough water to with stand a one-hour ten-year storm. The transportation
design and aspects are along Canal Street. These roads will require new subsurface and paving as they
will be removed to install the new interceptor pipe and conveyance pipe system for the CSO renovation.
F. 3.0. Pre-Development Conditions
The project site for the Peru CSO involves both undeveloped and developed areas of land. On the north
side of the Wabash River, there is the downtown area of the city of Peru where the piping system will be
collecting the waste water. This area has been developed and there is significant infrastructure in this
area of the site. South of the Wabash, adjacent to the existing waste water treatment plant there is a
farm field. This area is relatively level and is clear of any infrastructure. The areas where this project will
be implemented are currently owned by the city of Peru.
F. 4.0. Transportations concepts
Subsurface design: Based on INDOT standards for below roadway piping
Capacity design: HDM 2010: 2 Lane Highway Design
Pavement design: AASHTO design method and APAI standards
Stripping design: MUTCD standards
Detour design: MUTCD standards
F. 5.0. Transportation Design Approach
F. 5.1. Piping backfill design
For the initial approach of this design, several options were explored and ruled inappropriate for this
aspect of the project, the first being the materials used for the pipe. There were several sources studied
to evaluate the use of a plastic or flexible pipe for this system. Given the volumes and flow rates
anticipated for this system, this type of material was deemed inappropriate. With this, the assumption
was made that a rigid pipe material would be used: concrete, ductile iron, etc. Another option that was
deemed inappropriate was an imported new material as a structural backfill beneath the pipe. The
typical structural backfill is only required provided the pipe is resting on or near the bedrock layer of the
subsurface, or a flexible material is used. Upon further review, neither of these options are viable for
this system. A structural backfill will not be required based on this research and analysis.
86. 2
The backfill that can be used for the material above the pipe will be the existing soils/material found
beneath the roadway. Based on the type of soil seen below the roadway, there are certain compaction
requirements necessary for this to be appropriate. These are requirements are provided by the
American Concrete Pipe Association.
87. 3
Figure F.1: Illustration 4.4 Standard Installations Soil and Minimum Compaction Requirements
Figure F.2: Illustration 4.5 Equivalent USCE and AASHTO Soil Classifications for SIDD Soil Designations
This method was deemed appropriate as the materials below the roadway currently support both the
roadway and existing piping below the surface.
The backfill for the interceptor and conveyance pipe will be in accordance with INDOT Specification
211.02 for a B Borrow. A compacted earthen backfill will be used to hold the pipe in place. The
specifications of the material required for this can be found in Section 211.02 of the INDOT Standard
Specification Manual. The cut section below shows the criteria for this type of backfill from INDOT
Standard Drawing No. 715-BKFL-01. Several of the dimensions of the geotechnical backfill are based on
the diameter of the pipe.
88. 4
Figure F.3: INDOT Standard Drawing No. 715-BKFL-01
INDOT also provides another view based on the type of roadway that is to be designed. For this design,
we will be using a Hot Mix Asphalt (HMA) design. The figure below can be found as INDOT Standard
Drawing No. E 715-BKFL-03.
89. 5
Figure F.4: INDOT Standard Drawing No. E 715-BKFL-03
F. 5.2. Capacity Design
For the design of the roadway, the traffic data used needed to be interpreted and converted to
determine the size and regulated speed of the roadway. One of the sources was the data provided by
our client. This included station count data from the count station throughout Indiana as well as in
Miami County specifically. The other source used was the traffic count data collected from the second
site visit. Several processes were attempted to create the most accurate interpretation of what was
actually happing in the use of this road as well as its design and capacities. The method that provided
the most appropriate interpretation and the most reasonable results was through the Highway Capacity
Manual (HCM). Using this manual the most accurate interpretation of Canal Street was the
“Uninterrupted Flow: 2-lane highways”. Below are the results of this analysis and attached are the full
calculations and references.
90. 6
Table. F.1: Canal Street Capacity Design Results
F. 5.3. Pavement Design
The recorded flow volumes were then also used for the pavement design of the roadway. The AASHTO
standards and procedures were also used for this design as well. The figure below shows the conversion
of the flow volumes into ESALs to determine the loading capacities needed for the roadway.
Calculation Summary Sheet
Design Volume East to West 7008
Design Hourly Volume Analysis
Average Annual Daily Traffic (ADT)
AADT 7008 vpd
Design Hourly Volume (DHV)
30th Highest Hourly Volume
Hourly Traffic % of ADDT 15.5 %
DHV 1086.24 vph
DHV 1086 vph
DHV (Per Lane) 543 vph
HCM 2010: Chap. 15
Class III: (PFFS)
FFS 37.4 mph
Vi, ATS 593.00 pch
ATS,d 26.40 mph
PFFS 0.7060 percentage
"=>LOS D"
Capacity (Cd,ATS) 1559 pch
v/c Ratio 0.380
Required Number of Lanes in 1
Direction - N 1 Lanes
Required Total Number of
Freeway Lanes 2 Lanes
91. 7
Table F.2: ESAL Calculation Results
ESALs Calculations
Total Traffic
(annual) 3924480
Percentage of
Semi's 10%
Number of Semi's 3924
Nominal Semi
Weight (ESALs) 2.44
Annual ESALs 9575
This annual value is considerably low. The minimum value for the loading capacity is 50,000. It was then
determined that 100,000 ESALs would be an appropriate loading with this roadway seeing both semi
and school bus traffic activity based on the standard loading capacities from AASHTO. See the attached
sheets for the process and calculations for the Canal Street pavement design.
The remainder of the AASHTO pavement design method requires knowledge and data on the subsurface
soil properties where the road will be constructed (Huang, 1993). This information was not available for
this design. AASHTO provides minimum thickness requirements for roadways based on the calculated
road loadings. As a result, the loading capacity was used as the design criteria for the pavement design
of this roadway. The standards used to determine the pavement design based on this data is from APAI
(Asphalt Pavement Association Indiana) referencing INDOT Standard Specification 402.
92. 8
Table F.3: INDOT Section 402.04 Design Mix Formula
Reference Drawing T5.0 and attached evaluation for pavement design characteristics.
F. 5.4. Curb and Gutter Design
Based on INDOT Standards and Transportation consultation, a typical curb and gutter cross-section was
designed for both sides of Canal Street where it would require such a system. Based on the aerial
photographs of Canal Street, curb and gutter is located on either side of the Canal Street/Highway 19
intersection. Curb and gutter then runs to the next perpendicular intersection on either side. After these
intersections, there appears to be no curb and gutter system as the runoff will not be significant enough
to require such a system. The curb and gutter system was designed as a 6”x6” curb with a 24” flange
extending into the roadway’s width. This was deemed appropriate based on INDOT standards and
transportation consultation. See Drawing T4.0 for the typical curb and gutter cross-section.
F. 5.4. Detour Design
A detour design will be required for the construction process of the interceptor pipe and the repaving of
Canal Street. For this design, the Manual on Uniform Traffic Control Devices (MUTCD) detour signage
plan was used. For the typical layout design the “Figure 6H-20 – Typical Application 20 Detour for Closed
Street” in Part 6 – Temporary Traffic Control was used as a guideline.
93. 9
Figure F.5: Figure 6H-20: Detour for a Closed Street (TA-20)
Using this signage set up, a typical layout of the signage was developed for the auxiliary roads that
create T-intersections with Canal Street. See Drawing T6.0 for Standard Detour Plan and Schedule.
94. 10
F. 5.5. Striping and Marking Design
The striping and roadway markings were designed and specified using the MUTCD as well. Using the
MUTCD: Part 3 – Markings, the road marking meet standard specifications for cross-sections, center
lines, and directional arrows. See Drawing T1.0 for the pavement marking layout for the Highway
19/Canal Street intersection. The remaining spans of the road only require the typical two-lane, two-way
marking with passing permitted in both directions. Aerial photos of the current roadway were used as
well as a guide to the striping design.
Figure F.6: Figure 3B-13. Examples of Line Extensions through Intersections
95. 11
F.5.6. Resources
American Association of State Highway and Transportation and Operations (AASHTO). (2011). “Roadside
Design Guide: 4th
Edition”
American Concrete Pipe Association (ACPA). (2011). Concrete Pipe Design Manual. Chapter 4: Loads and
Supporting Strengths. Library of Congress catalog number 78-58624
Asphalt Pavement Association of Indiana (APAI). (2009). “Guide for Specifying Asphalt Pavements for
Local Governments (Using INDOT Standard Specifications Section 402)”
Highway Design Capacity (HCM). (2010). Volume 2: Uninterrupted flow. “2-Lane Highways”.
Huang Y. H. (1993). “Pavement Analysis and Design”, 1st
edition, Prentice Hall, Englewood
Cliffs, NJ.
Indiana Department of Transportation (INDOT). (2013). Standards and Specifications. “Section 700:
Structures”.
Manual on Uniform Traffic Control Devices for Streets and Highways (MUTCD). (2009). “Part 6 Traffic
Control”
Standard Highway Signs (SHS). (2004). “2012 Supplement: For use with the 2009 Manual on Uniform
Traffic Control Devices for Streets and Highways.”
108. 1
G.1 Introduction
The work detailed in this appendix describes the efforts of MASE Consultants Co. to produce a hydraulic
model to analyze the combined sewer overflow (CSO) events of Peru, IN, the current capacity of the
combined sewer system, and design a new interceptor pipe and conveyance pipe as well as upgrade the
pump station. The hydraulic model described in this appendix is the main analysis tool used in this
portion of the project. The first objective in using this model is to identify the extent of the CSO events
being produced in the existing system. The second objective in using this model is to build a better
system that can effectively convey of the 10-year, 1-hour design storm.
G.2 Project Description
The city of Peru contains 85 miles of underground sewer pipe networks. Approximately three-fourths of
these pipes feed into the intersecting pipe on the north side of the Wabash River. The combined sewer
overflow is collected by an interceptor pipe and transported to a pump station where it is then pumped
through a conveyance pipe located beneath the Wabash River to the waste water treatment plant
(WWTP). Currently, the interceptor pipe, pump station, and conveyance pipe cannot adequately convey
with the combined sewage that is produced during storm events. The combined sewer overflow
treatment process will be redesigned to better transport the sewage to the waste water treatment
plant.
G.3 Current Conditions
The waste water treatment plant is designed for a daily flow rating of eight million gallons per day
(MGD) and has a maximum flow capacity of 26 MGD. It is at present running at 50 percent capacity with
4 MGD being received during dry weather periods. Approximately 90% of the pipes on the north side of
the Wabash flow into the interceptor pipe which feeds into the Cass Street Pump Station. The other 10%
of the pipes are located on the southern side of the Wabash and separately flow into the WWTP. The
interceptor pipe ranges from 12 to 27 inches in diameter and is presently able to convey a flow rate of
14 MGD to the pump station. The pump station has a capacity of 19.6 MGD and the current force main
is two feet in diameter.
On average, 26 combined sewer overflows occur each year. These overflow events are the result of the
collection system not being large enough to effectively convey the wastewater as well as the
wastewater treatment plant’s inability to treat the incoming flows.
G.4 Design Concept
To relieve the existing system of CSO events, our team has developed a design option to increase its
efficiency. This design includes replacing the interceptor and force main to better contain the actual
flows and upgrading the pump station to better transfer the incoming flow demand. With an upgraded
system, the number of CSO events will be reduced to zero at the design storm conditions. In order to
analyze these solutions in this complex system we employed the use of hydraulic modeling software
known as Storm Water Management Model (SWMM). SWWM was suggested by our client because of
its ability to model both the hydrology of the urban watershed and the collection system. We used the
109. 2
model to determine the diameter of the new interceptor pipeline and force main and design a new
pump station.
G.5 Modeling Approach
A simplified version of the collection system was developed for the model, see Figure G.1. An AutoCAD
file of the collection system provided to the team by Lochmueller Group was used to produce the
collection system in SWMM. The model was run using the Dynamic Wave routing method and the
Hazen-Williams force main equation.
The simplified model represents the relationship between the urban watershed and collection system.
The delineated watershed consists of 11 subcatchments on the northern side of the Wabash River and
one subcatchment on the southern side. In order to determine the amount of flow reaching the
interceptor pipe, a system of junctions and conduits connecting to the interceptor pipe was created
within each subcatchment. The runoff from each subcatchment was directed to the end node of each
designated subcatchment.
Figure G.1: A schematic of the Peru combined sewer system as created in SWMM. This
depicts the modeling approached used to understand the manner at which the flow
feeds into the interceptor.
110. 3
G.5.1 Existing System
The following sections include the input values from the subcatchment, conduit, junction, and rain gage.
G.5.2 Rain Gage Values
In the SWMM model, rain gages were used as an inlet value for the subcatchments. The time series
represented in Figure G.2 below was used to calibrate the model for current conditions. After the
calibration, the 10-year, 1-hour storm was simulated with the model (See Figure G.3).
Figure G.2: Rain event on August 31, 2013
Figure G.3: Design Storm 10-year, 1-hour
0
0.02
0.04
0.06
0.08
0.1
0.12
0.14
0.16
0.18
0.2
0 0.02 0.04 0.06 0.08 0.1 0.12 0.14
Rainfall(in)
Time (hr)
Rain Gage Time Series
0
0.02
0.04
0.06
0.08
0.1
0.12
0.14
0 10 20 30 40 50 60
Rainfall(in)
Time (min)
10-year, 1-year
111. 4
G.5.3 Subcatchment Input values
To analyze the combined sewer system, the subcatchments draining into it were first identified. Using a
delineation provided by Lochmueller Group, a new delineation was created that best represents the
runoff reaching the combined sewer system in the design storm. Further explanation of the watershed
modeling can be found in Appendix E. The parameters necessary to model the subcatchments include:
area, percent impervious, slope, curve number, and overland flow width (OFW). (See Table G.1).
Table G.1: Input values for the subcatchment analysis portion of the design.
Subcatchment Area (ft2
) % Imperv Slope Curve Numb. OFW (ft)
S1 140 46.4 1.8 68.92 5
S2 140 38.2 1.5 69.75 7
S3 115 30 1 72 2
S4 70 38 1.4 75 5
S5 175 52.7 1 8198 8
S6 65 85 0.6 92 5
S7 55 38 0.6 85 5
S8 210 65 0.2 85 5
S9 230 82.9 0.3 79.87 8
S10 60 65 0.8 85 4
S11 40 65 1.17 85 1
S12 65 38 2 75 1
G.5.4 Conduit Input Values
The different depths within each pipeline are separated by junction nodes. The input parameters
needed to analyze the conduit were depth, shape, material, roughness and length of the pipe (See Table
G.2 and Figure G.4). The roughness coefficient is related to the assumed average smoothness texture of
the assumed concrete material of the pipes which are also assumed to be old. The depth, shape and
length of the pipes were supplied by the Lochmueller Group.
113. 6
Table G.2: Material, shape, depth, roughness and length of the pipe lines throughout the piping system
of Peru. The length is the sum of all the conduits comprising the individual lines.
Pipe Line Material Shape Diameter (in) Roughness Length (ft)
1 Concrete Circular 12 0.015 2857.88
2 Concrete Circular 20 0.015 2268.73
3 Concrete Circular 20 0.015 1250.50
4 Concrete Circular 54 0.015 2057.86
5 Concrete Circular 20 0.015 1284.22
6 Concrete Circular 20 0.015 1002.26
7 Concrete Rectangular 30 0.015 6417.39
8 Concrete Rectangular 30 0.015 3946.31
9 Concrete Circular 20 0.015 1606.23
10 Concrete Circular 20 0.015 640.98
11 Concrete Circular 12 0.015 1879.78
12 Concrete Circular 12 0.015 1245.61
G.5.5 Junction Input Values
The junction parameters that required elevation were the invert elevation and the maximum depth of
the junctions. The invert elevations used were the elevations that matched the direction of flow and the
maximum depth was derived from the difference between the invert elevation used and the elevation
of the surface of the junction, or the rim elevation. Table G.3 below has the invert elevation of each
junction and Figure G.5 depicts the location of each node mentioned in the previous table.
115. 8
Figure G.5: Model with nodes labeled.
G.5.6 Pump Input Values
The Cass Street Pump Station was implemented into the model. In SWMM, the pump is represented as a
link within the model and connects the junctions much like a conduit link. The required parameters for
the pump are the curve number and the inlet and outlet junctions. The pump was categorized as type
three. The type of pump determines the parameters required by the model. The parameters required
for type three pumps are head in feet and flow in million gallons per day.
The pump curve for the existing pumps was provided by the Lochmueller Group. Inputting the current
pump parameters into the model was needed in order to accurately model the current CSO events. The
Cass Street Pump Station has four Fairbanks Morse pull-up submersible pumps; three of the pumps are
10” D5435MV and the fourth is an 8”D5435MV. The sizes depict the capacity of the pumps. Table G.4
depicts the calculations used to determine the system curve. Figure G.6 is the system curve that the
current flow conditions require from the pump station.
116. 9
Table G.4: Example inputs of the variables used to produce the system curve.
L (ft) D (ft) CHw
Q
(MGD) Q (gpm) K
Head Loss
(ft)
4308.34 2 120 4 2777.778 0.099236 2.889711
4308.34 2 120 10 6944.444 0.099236 15.7414
4308.34 2 120 16 11111.11 0.099236 37.55479
4308.34 2 120 22 15277.78 0.099236 67.69013
4308.34 2 120 28 19444.44 0.099236 105.7513
4308.34 2 120 34 23611.11 0.099236 151.4535
4308.34 2 120 40 27777.78 0.099236 204.5759
Figure G.6: System curve required for top efficiency of pump station within the existing system.
G.5.7 Calibration of Existing Collection System
To ensure that the model of existing collection system was accurate, we used pollutograph flow data
given to us by our client. We chose two storms August 31st
, 2013 and April 25th
, 2014, to calibrate the
model. The storms were chosen because they provide data for a short duration of storm high intensity
and a long duration low intensity. We found the volume of the flow under the pollutograph flow graphs
and compared the values to the data generated from the model. Figures G.7 and G.8 are the graphs
given to us by our clients.
0
1000
2000
3000
4000
5000
6000
0 50000 100000 150000 200000
Head(ft)
Flow (GPM)
System Curve
117. 10
Figure G.7: August 31st
, 2013 data used for calibration. The data compared to the data generated by the
model was the mgd section of the graph.
Figure G.8: April 25st
, 2014 data used for calibration. The data compared to the data generated by the
model was the mgd section of the graph.
118. 11
G.5.8 Model Calibration
The original model did not output comparable data. In order to better represent the existing collection
system, we made adjustments to the subcatchment parameters that control the amount of runoff which
flows into the collection system. The parameters adjusted were the subcatchment areas, or the land
area of each individual subcatchment, overland flow widths, the area the water flows over and the curve
numbers which represent the type of land in each subcatchment. Other adjustments were made to the
percent impervious area within the subcatchment to represent the street pavements. The last
subcatchment adjustment made to decrease runoff was a decrease in impervious area with no
depression storage in some of the subcatchments. This increased the amount of natural storage and
therefore decreasing the runoff reaching the collection system. Adjustments were also made to the pipe
parameters within the model. We adjusted the roughness of the pipes from 0.01 to 0.015 to better
represent the dated concrete material making up the pipes. The alterations made to better calibrate the
model were within the range of what each parameter would be. The model was run with the new
parameters and generated more comparable output data. Figures G.9 and G.10 are the outflow data
corresponding to the storm data used.
Figure G.9: Outflow data generated by the system using the rain event data from August 31st
, 2013.
119. 12
Figure G.10: Outflow data generated by the system using the rain event data from April 25th
, 2014.
Once the outputs produced by the model were trending similarly with the graphs provided by our client,
we used a third storm to calibrate the model. The third storm data also came from the client but was
produced by an outside company, Strand Associates (2012). This storm was a 10-year, 4-hour storm and
better represented the storm for which we would be designing the new collection system. Figures G.11
and G.12 are the hydrograph produced by Strand Associates and the hydrograph produced by our
model.
120. 13
Figure G.11: Hydrograph of 10-year, 4-hour storm produced by Strand Associates.
Figure G.12: Outflow data generated by our system using the 10-year, 4-hour rain event data from
Strand Associates.
121. 14
G.6 Existing Conditions Outputs
After entering the parameters previously mentioned in the above sections into the model, the storm
data in the design storm time series was simulated. The simulated storm’s effect on the interceptor
pipeline was then studied. Table G.5 represents the junctions and conduits overflowing from the design
storm. After analyzing the flooding of the current system due to the design storm, we determined the
conduits that needed resizing throughout the interceptor system in order to reduce the CSO events and
determined the capacity to which the pump needed to be resized.
Table G.5: The junctions that surcharge or overflow from the amount of rain resulting from the design
storm.
Node Hours Flooded Max Rate MGD
Total Flood
Volume 106
gal
J168 10.81 7.752 1.419
J895 0.01 2.632 0.00
CSO2 6.75 4.294 0.366
CSO4 0.01 2.632 0.002
CSO3 4.23 11.336 0.812
CSO6 0.03 111.975 0.057
CSO12 2.47 5.043 0.306
CSO14 57.03 14.192 7.381
CSO15 13.85 9.651 0.821
CSO16 0.01 4.911 0.00
G.7 Design Approach
This section will describe the new inputs used that increased the interceptor pipe’s capacity for the 10-
year, 1-hour design storm. Because the CSO events occur due to flooding within the nodes, or pipe
junctions, we simulated sealing off the CSO outlets in the model while the design storm was simulated.
Removing the CSO outlets allowed for the conduits to be resized in order to eliminate pipe junction
flooding and therefore, CSO events.
G.7.1 Conduit Input Values
In the previous section, the conduits that could not accommodate the new incoming flow were
identified from the flooded node results generated by the model. We then used the model to resize the
interceptor and the force main. This was done through a trial and error approach of running the storm
simulation and resizing the pipes to eliminate pipe junction flooding. The improved conduit input values
are in Table G.6.
122. 15
Table G.6: New depth or diameter of surcharging conduits and the resulting velocity within the new
sizes.
The new diameters of the interceptor pipe sections eliminated flooding in the nodes and CSO events. No
flooding and CSO events allowed for larger amounts of flow to pass through the interceptor pipe and
reach the Cass Street pump station. Figure G.13 represents the new flow rate that will reach the pump
station after the new interceptor installation.
Conduit
Original
Depth (ft)
New Depth
(ft) Length (ft)
C951 1.25 4.00 1174.76
C955 1.25 4.50 1341.35
C954 1.27 5.50 1219.60
C956 2.00 7.00 467.55
C957 2.00 6.00 859.35
C958 2.25 7.75 821.49
C843 2.25 7.00 14.34
C828 2.25 5.00 47.35
C959 1.50 5.00 461.50
C809 1.00 5.00 833.94
C808 1.00 5.00 1277.00
C987 0.50 6.00 1353.00
Force Main 2.00 4.00 4308.34
123. 16
Figure G.13: Total flow going into the Cass Station pump station.
G.7.2 Pump Resizing
With a larger flow passing through the pump station, the pumps needed resized. To determine the
amount of power required by the pump to transfer the wastewater through the force main, pump head
was calculated using Hazen-Williams equations. The pump head accounts for the difference in elevation
and friction head loss of the force main. The friction head loss is dependent on the length of the force
main, the Hazen-Williams coefficient, the diameter of the force main, and the flow rate within the pipe.
Below are the required equations used.
𝐻 𝑝 = 𝐾𝑄1.85
𝐾 =
4.73𝐿
𝐷4.87 𝐶 𝐻𝑊
1.85
The head loss the pump needs to overcome is 19.70 feet for the design flow passing through the
collection system. Table G.7 depicts the values used to determine the system curve. Figure G.14
represents the new system curve required to transfer the flow through the force main.
124. 17
Table G.7: These are the values used within the system curve calculations.
L (ft) D (ft) CHw K
4308.34 4 120 0.003394
Figure G.14: System curve required for the new collection system flow.
Because the flow is so large, four pumps in parallel will be required to effectively transfer it. Four
Fairbanks pumps of the same style as the original pumps at the existing pump station were selected to
replace the original pumps. The new pumps will be 24” 5731 W, WD Submersible Angleflow Pumps. One
pump can transfer the lowest flow of four million gallons per day during dry weather and the four in
parallel will be able to handle the design storm flow. Figure G.15 is the pump curve of the new pumps.
0
20
40
60
80
100
120
140
160
180
200
0 50000 100000 150000 200000
HeadLoss(ft)
Flow (GPM)
System Curve
125. 18
Figure G.15: The new pump size of the four pumps to replace the current pumps at the Cass Street
Pump Station. The bold lines indicate the operating point on the curve.
G.7.3 Designing for the Future
When generated into the model, the new improvements hold up well for current conditions and the 10-
year, 1-hour design storm. To equip the system for a larger storm or a larger population, two CSO
outlets were left open in the interceptor design. The locations of the CSO outlets were determined by
the change in diameter throughout the interceptor. CSO 3 and CSO 12 were left open to relieve flooding
from future storms larger than the design storm. A CSO outlet was left open at the nodes connecting
two pipes with the upstream pipe diameter being larger than the downstream pipe diameter. This
relieves the node of any flooding that might occur during a larger storm event. Leaving the CSO outlets
open is a safety measure to ensure that the system will not back up and destroy property or cause harm
to the citizens of Peru’s health or financial welfare. These CSO outlet locations are represented in Figure
G.16.
126. 19
Figure G.16: The two CSO outlets left open in the new design are located at pipe contractions from
upstream to downstream flow.
G.7.4 Results Summary
By enlarging the interceptor pipe and the force main, CSO events will not occur in the event of a 10-year,
1-hour storm. The two CSO outlets that were left open will be left to protect the citizens of Peru from
any back up.
127. 20
G.8 References
Crawford, Murphy & Tilly (CMT). (2014). “Wastewater Treatment Plant Upgrade Peru, Indiana”
http://www.cmtengr.com/proj_wr_peru.html (December 2014).
Strand Associates, Inc. (2012). Combined Sewer Overflow (CSO) Long Term Control Plan (LTCP) Analysis,
Indianapolis, IN, 1-2.
