HomeMy WebLinkAbout4801 Akers Road - Sewer Study
Sewer Study for APN 404-010-46
For:
Shawn Bidsal
Akers LLC
May, 2015
Submitted To:
Bakersfield Public Works Department
1600 Truxtun Avenue
Bakersfield, CA 93301
Table of Contents
Table of Figures ............................................................................................................................................ iii
Table of Tables ............................................................................................................................................. iv
Executive Summary ....................................................................................................................................... 2
Objective ....................................................................................................................................................... 4
Existing Facilities ........................................................................................................................................... 4
Planned Land Uses ........................................................................................................................................ 5
Phasing .......................................................................................................................................................... 7
Field Study ..................................................................................................................................................... 7
Design ............................................................................................................................................................ 8
Sewer System Analysis/Results ................................................................................................................... 10
Akers 10” Line Conclusion ........................................................................................................................... 13
Field Study ................................................................................................................................................... 14
Conclusion ................................................................................................................................................... 16
Sewer System Peak Flow Calculations ........................................................................................................ 43
Appendix A .................................................................................................................................................. 55
ii
Table of Figures
Executive Summary Figure ............................................................................................................................ 3
Figure 1 – Parcel Area ................................................................................................................................... 4
Figure 2 – Wastewater Travel Path ............................................................................................................... 5
Figure 3 – Site Layout .................................................................................................................................... 6
Figure 4a – Original Zoning ........................................................................................................................... 6
Figure 4b – Current Zoning ........................................................................................................................... 6
Figure 5 – Monitoring Locations ................................................................................................................... 7
Figure 6a – Sewer Zoning and Pipe Size Legend ......................................................................................... 18
Figure 6b – Sewer Lines and Test Locations ............................................................................................... 19
Figure 6c – Sewer Lines with Zoning Information ....................................................................................... 20
Figure 7a – Stine Sewer Lines...................................................................................................................... 21
Figure 7b – Akers S of White Ln Sewer System ........................................................................................... 22
Figure 7c – Akers S of White Ln Detailed Area (Project Site and Single-Family Residential) ...................... 23
Figure 7d – White Ln E of Akers Sewer System .......................................................................................... 24
Figure 7e – Akers N of White Ln Sewer System .......................................................................................... 25
Figure 7f – Stine N of White Ln Sewer System ............................................................................................ 26
Figure 7g – White Ln E of Stine Sewer System ............................................................................................ 27
Figure 7h – Stine and Pacheco Sewer System ............................................................................................ 28
Figure 7i – Harris and Stine Sewer System ................................................................................................. 29
Figure 7j – Panama and Stine Sewer System .............................................................................................. 30
Figure 7k – Stine N of McCutchen Sewer System ....................................................................................... 31
Figure 7l – Hosking Sewer Lines .................................................................................................................. 32
Figure 7m – McCutchen Sewer Lines .......................................................................................................... 33
Figure 7n – Ashe Sewer Lines ...................................................................................................................... 34
Figure 8 – Stine Harris (27”) ........................................................................................................................ 35
Figure 9 – Stine and Panama (27”) ............................................................................................................. 36
Figure 10 – Stine and McCutchen (30”) ...................................................................................................... 37
Figure 11 – McCutchen and Breccia (36”) .................................................................................................. 38
Figure 12 – McCutchen and Ashe (48”) ...................................................................................................... 39
Figure 13 – Paper on the Ledge (Stine Rd N of McCutchen Manhole Tube) .............................................. 40
Figure 14 – McCutchen and Breccia Manhole Tube ................................................................................... 41
Figure 15 – McCutchen and Ashe Manhole Tube ....................................................................................... 42
iii
Table of Tables
Table 1 – Original with Single-Family .......................................................................................................... 10
Table 2a – Current with Single-Family ........................................................................................................ 11
Table 2b – Current with Single-Family ........................................................................................................ 11
Table 3 – Original without Single-Family .................................................................................................... 12
Table 4 – Current without Single-Family ..................................................................................................... 12
Table 5 – System Deltas .............................................................................................................................. 13
Table 6 – Current with Single-Family, without Oil Field ............................................................................. 13
Table 7 – Akers 10” Pipe ............................................................................................................................. 14
Table 8 – Field Study Manual Readings ...................................................................................................... 15
Table 9 – System Deltas .............................................................................................................................. 16
Table 10 – Pipe Capacities .......................................................................................................................... 16
iv
Executive Summary
This report details the effects to the sewer system of developing an apartment and an industrial
complex on APN 404-010-46.
APN 404-010-46 was originally zoned as all M1/M2 industrial. As part of this project, the parcel has had
22.87 acres rezoned as R2 residential, and 2.53 acres removed and dedicated to the City of Bakersfield
for Akers Rd. By making these changes to the parcel, we have also changed the contribution of the
parcel to the sewer system.
The parcel connects to the sewer line on Akers Rd that travels north and connects to the sewer line on
White Ln. Besides serving our parcel, this sewer line also serves a small single-family residential
neighborhood. The original contribution of the parcel and single-family neighborhood was 0.78 MGD
(1.20 cfs). The current contribution of the parcel and single-family neighborhood is 0.76 MGD (1.18 cfs).
Thus, by altering the zoning of the parcel, we have reduced the load on the sewer system.
In addition to the numerical analysis performed on the sewer system, we were also required to install
flow meters into the system at five different locations for a time period of one to two weeks. During the
monitoring time period, the depth of flow never surpassed 79% of any of the monitored pipe’s
capacities. The minimum excess capacity in these pipes was 1.25 MGD (1.93 cfs), which is greater than
the 0.59 MGD (0.91 cfs) our parcel could contribute to the system.
Based upon our analysis, combined with the field study, the existing sewer system has the available
capacity to accommodate the proposed development and is adequate for its proposed use.
A summary showing our project site location, the path of travel for the sewage, main sewer line sizes,
water flow monitoring locations (pink circles), and the max depths at these locations during our period
of study can be seen in the figure below.
2
Executive Summary Figure
3
Objective
The objective of this study is to determine the impact to the existing sewer system of building an
apartment and an industrial complex on Assessor’s Parcel Number (APN) 404-010-46.
Existing Facilities
The land is currently undeveloped, with the exception of an oil field that occupies 8.61 acres in the SW
corner of the lot. To the plots immediate north is a small single-family residential area. The land is
bordered, on its other three sides, by light and general manufacturing facilities (see Figure 1).
Figure 1 – Parcel Area
The sewage from the apartment complex, and the planned industrial complex (there are no plans to
connect the oil field to the city sewer system), will flow to the north of the property and be collected by
a 10” sewer pipe on Akers Rd that also serves the residential community there. The effluent will travel
further north from where it initially connects into the pipe before connecting to a main sewer line that
flows from east to west on White Ln. This line then connects to the main line on Stine Rd, and flows
4
south to meet the main trunk line on McCutchen Rd, which flows west to Wastewater Treatment Plant
#3 (WWTP3). (See Figure 2)
Figure 2 – Wastewater Travel Path
Planned Land Uses
APN 404-010-46 is planned to have a 396 unit apartment complex and a 62 lot industrial complex. (See
Figure 3) The parcel was originally zoned all M1/M2 industrial. (See Figure 4a) In order to be able to
build the apartment complex, the parcel was rezoned to be a mix of R2 residential and M1/M2
industrial. (See Figure 4b)
5
Figure 3 – Site Layout
Figure 4a – Original Zoning
Figure 4b – Current Zoning
The parcel has been restructured where 22.87 acres of the parcel have been reconfigured to zone R2 in
order to house the 396 unit housing complex. Approximately 2.53 acres have been dedicated to the City
of Bakersfield for Akers Rd, and thus have been removed from the parcel. The remaining 36.81 acres,
8.61 acres of which is used as an oil drill island, have not changed from their original industrial zoning.
6
Phasing
Phasing is still yet to be finalized. However, tentative plans for phasing have the apartment and
industrial complexes being built in four phases.
Field Study
Part of the requirement for this report was to conduct a field study of the sewer system. To do this, we
installed water flow loggers (model number FL16U by Global Water, see Appendix A for the datasheet)
in the sewer pipes at five locations along the route from the proposed project site to the waste water
treatment plant. The water flow loggers were set to record depth of flow readings at 30sec to 2 min
intervals. The locations were (see Figure 5):
1) The manhole north of the intersection of Stine Rd and Harris Rd
a. Recordings taken from 4/13 to 4/20
2) The manhole north of the intersection of Stine Rd and Panama Ln
a. Recordings taken from 4/22 to 4/28
3) The manhole north of the intersection of Stine Rd and McCutchen Rd
a. Recordings taken from 4/22 to 4/28
4) The manhole at the intersection of Breccia and McCutchen Rd
a. Recordings taken from 4/13 to 4/20
5) The manhole west of the intersection of Ashe Rd and McCutchen Rd
a. Recordings taken from 4/13 to 4/20 and 4/22 to 4/28
Figure 5 – Monitoring Locations
7
Design
The proposed development will be serviced by a 10” line on Akers Rd. 8” laterals will split off from this
line and run under each of the streets on-site. 6” lateral lines will service each apartment building and
4” lateral lines will connect to each industrial unit.
The following equations and sewage contribution factors were used to analyze the sewer system.
Manning’s Equation, 𝑉=�1.4859𝑛�𝑅ℎ2 3⁄𝑆1 2⁄
V = cross-sectional average velocity (ft/s)
n = Gauckler-Manning coefficient (𝑠𝑚1 3⁄�) = 0.013
1.4859 = conversion from SI to US units
S = slope of the grade line (unitless)
Rh = hydraulic radius (ft)
Rh = A/P (ft)
A = cross-sectional area of the flow (ft2)
P = wetted perimeter (ft)
A = 𝑅2 cos−1�𝑟𝑅��−𝑟√𝑅2 −𝑟2
R = radius of the pipe (ft)
r = radius – height of the effluent level (negative if > 50% full) (ft)
P = 2Rcos−1(𝑟𝑅)⁄
Q = volumetric flow rate (cfs)
Q = A V
Q = A�1.4859𝑛�(𝑅ℎ)2 3⁄𝑆1 2⁄
Q = A�1.4859𝑛�(𝐴𝑃)2 3⁄𝑆1 2⁄
Q = �1.4859𝑛���𝑅2cos−1�𝑟𝑅��−𝑟√𝑅2−𝑟2�5 3⁄[2Rcos−1(𝑟𝑅)⁄]2 3⁄�√𝑆
MGD = Millions of gallons per day
8
MGD = cfs ∗ 7.48 gal/𝑓𝑡3 ∗ 86,400 s/day1,000,000
Sewage Contribution Factors (values taken from Subdivision and Engineering Design Manual by the City
of Bakersfield Public Works Department):
Residential
Average Family Unit size = 2.6 for single-family residential and 2.0 for multi-family residential
Average daily discharge per person = 100 gallons per day
Design Discharge = Peak Factor x Average Discharge (MGD)
Peak Factor = 2.54 * (Average Discharge) (-0.1) (MGD)
Design Discharge = 2.54 * (Average Discharge)(0.9) (MGD)
Commercial
Average Discharge = 3589 gpd/ga = 0.003589 MGD/ga = 0.005556 cfs/ga (ga = gross acre)
Peak Factor = 1.8
Peak Discharge Rate = 0.006460 MGD/ga (6460 gpd/ga)
Industrial
Average Discharge = 4848 gpd/ga = 0.004848 MGD/ga = 0.0075 cfs/ga
Peak Factor = 2.0
Peak Discharge Rate = 0.009695 MGD/ga (9695 gpd/ga)
9
Sewer System Analysis/Results
In our analysis, we analyzed, in detail, the sewer mains nearest to our site. (See Figures 6a-6c for an
overview of the sewer system, including property zoning, contained within the scope of this study.
Figures 7a-7n show the service areas in greater detail.)
Akers – 10” Line
Our site drains into a 10” sewer line on Akers Rd between Pacheco Rd and White Ln. Sewage flows
north in this line at a slope of 0.16% towards White Ln. It serves our site as well as a small single-family
residential neighborhood to the north. Using the formulae and contribution factors stated above, the
original zoning of the parcel, combined with the single family residential neighborhood located to the
north of the parcel contributed 0.78 MGD (1.20 cfs) to the sewer line at the intersection of Akers Rd and
White Ln. (see Table 1)
Table 1 – Original with Single-Family
The current zoning of the parcel, combined with the single family residential neighborhood to the north
of the parcel contributes only 0.76 MGD (1.18 cfs). (see Table 2a)
Persons / Single-
Family Dwelling
Persons / Multi-
Family Dwelling
Gallons / Day
/ Person
Peak Factor
Coefficient
Commercial
Discharge
(MGD/GA)
Commercial
Peak Factor
Industrial
Discharge
(MGD/GA)
Industrial
Peak Factor
2.6 2 100 2.54 0.00358889 1.8 0.0048475 2
Sewage Contribution Factors
Zone
Single-Family
(dwellings)
Multi-Family
(dwellings)
Industrial
(acres)
Acreage
(acres)
Average Flow
(MGD)
Average Cumulative
Flow (MGD)
Peak
Factor
Peak Design
Flow (MGD)
Peak Design
Flow (cfs)
R1 194 0.05 0.05 3.42 0.17 0.27
R2 0 0 0.00 0.05 3.42 0.17 0.27
M1/M2 23.73 23.73 0.12 0.12 2.00
M1/M2 9.42 9.42 0.05 0.16 2.00
M1/M2 29.06 29.06 0.14 0.30 2.00 0.60 0.93
194 0 62.21 62.21 0.78 1.20
Original Zoning, Single-Family Residential Included
Residential
Industrial
Total
10
Table 2a – Current with Single-Family
By changing the zoning of the parcel, the load on the sewer system has actually been reduced by 0.02
MGD (0.02 cfs). Table 2b shows the exact same information as Table 2a, only in a more compact way,
and will be the method shown henceforth.
Table 2b – Current with Single-Family
Akers – 10” Line: A Breakdown
To show why the load on the sewer system has been reduced, we have broken down the contributing
sections into further detail.
The original zoning for this parcel was all M1 & M2 industrial. Using the formulae and contribution
factors stated above, the original 62.21 acres of industrial zone contributed 0.60 MGD (0.93 cfs) (table 3)
to the sewer system.
Zone
Single-Family
(dwellings)
Multi-Family
(dwellings)
Industrial
(acres)
Acreage
(acres)
Average Flow
(MGD)
Average Cumulative
Flow (MGD)
Peak
Factor
Peak Design
Flow (MGD)
Peak Design
Flow (cfs)
R1 194 0.05 0.05 3.42 0.17 0.27
R2 396 22.87 0.08 0.13 3.12 0.40 0.63
M1/M2 8.95 8.95 0.04 0.04 2.00
M1/M2 27.86 27.86 0.14 0.18 2.00 0.36 0.55
Akers 2.53 0 0 0.00 0
194 396 36.81 62.21 0.76 1.18
Current Zoning, Single-Family Residential Included
Residential
Industrial
Total
Misc
Zone
Single-Family
(dwellings)
Multi-Family
(dwellings)
Industrial
(acres)
Acreage
(acres)Persons Peak Factor
Peak Design
Flow (MGD)
Peak Design
Flow (cfs)
R1 194 504.4 3.42
R2 396 22.87 792 3.27
M1 8.95 8.95 2.00 0.09 0.13
M2 27.86 27.86 2.00 0.27 0.42
Akers 2.53 0 0 0 0
totals 194 396 36.81 62.21 1296 3.12 0.76 1.18
Current Zoning, Single-Family Residential Included
0.40 0.63
11
Table 3 – Original without Single-Family
With the zoning modifications, the parcel contributes 0.62 MGD (0.95 cfs) to the sewer system (table 4).
As might be expected, the change from industrial to residential has increased the sewage contribution,
at the point at which sewage leaves the site. However, at the point where the sewage meets the 10”
sewer main on Akers Rd, the restructured zoning contributes less sewage than the full industrial
zoning (0.76 vs. 0.78 MGD (1.18 vs. 1.20 cfs), a reduction of 1.9%).
Table 4 – Current without Single-Family
To explain this, we have to look at the peak factors. As more and more residential units are added to
the system, the residential peak factor gets smaller and smaller. However, as more industrial acres are
added to the system, the industrial peak factor remains the same. When the full sewer line (up to White
Ln) is taken into consideration, 194 single-family residential units must be added into the sewage
calculations (see Figure 7c). With the added single-family residential units accounted for, the residential
peak factor decreases from 3.47 with the original zoning to 3.12 with the current zoning. It is this
reduction in the residential peak factor that accounts for the reduced load on the system created by
changing the zoning.
At the point where this sewer line intersects White Ln, it will have increased from 0.17 MGD (0.27 cfs) to
0.76 MGD (1.18 cfs) (See Table 5) [0.78 MGD (1.20 cfs) original parcel developed, 0.68 MGD (1.05 cfs) re-
zoned parcel no oil field (see Table 6)]. Thus, the apartment and industrial complexes account for an
increase of 292% sewage, 340% with the oil field, 349% original zoning, in this line, at this point. (See
Table 5) *Note: 0.68 MGD (1.05 cfs) is mentioned because we are not developing anything on the 8.61
Single-Family
(dwellings)
Multi-Family
(dwellings)
Industrial
(acres)
Acreage
(acres)
Peak
Factor
Peak Design
Flow (MGD)
Peak Design
Flow (cfs)
R1 0 0 #DIV/0!
R2 0 0 #DIV/0!
M1/M2 23.73 23.73 2.00 0.23 0.36
M1/M2 9.42 9.42 2.00 0.09 0.14
M1/M2 29.06 29.06 2.00 0.28 0.44
totals 0 0 62.21 62.21 #DIV/0!0.60 0.93
Original Zoning, Single-Family Residential Excluded
0.00 0.00
Single-Family
(dwellings)
Multi-Family
(dwellings)
Industrial
(acres)
Acreage
(acres)
Peak Design
Flow (MGD)
Peak Design
Flow (cfs)
R1 0 #DIV/0!
R2 396 22.87 3.27
M1 8.95 8.95 2.00 0.09 0.13
M2 27.86 27.86 2.00 0.27 0.42
Akers Rd 2.53 2 0
totals 0 396 36.81 62.21 3.27 0.62 0.95
0.40
Current Zoning, Single-Family Residential Excluded
0.26
12
acres of the parcel that are currently being used for oil drilling. The 0.76 MGD (1.18 cfs) and 0.78 MGD
(1.20 cfs) figures both include the oil field.
Table 5 – System Deltas
Table 6 – Current with Single-Family, without Oil Field
By developing these lands, we are increasing the peak flow in the 10” Akers sewer line by 0.50 MGD
(0.78 cfs) (0.17 MGD vs. 0.68 MGD) (0.27 cfs vs. 1.05 cfs), which is less than the 1.25 MGD (1.93 cfs) of
available capacity measured in the system (Calculations shown in Table 5 and Table 10, excess capacity
discussion found above and in the conclusion, page 12).
Akers 10” Line Conclusion
The original zoning of the areas utilizing this pipe required 0.78 MGD (1.20 cfs) of flow. By changing
the zoning of this area, the line will have less flow in it than the original zoning required (0.76 MGD vs.
0.78 MGD) (1.18 cfs vs. 1.20 cfs). We are not developing anything on the 8.61 acres of land that is
being used for oil drilling, so the delta between the original and what we are planning is even greater
at 0.68 MGD vs. 0.78 MGD (1.05 cfs vs. 1.20 cfs).
Further aiding the situation is the fact that the timing of the peak flows is different for the different
zone types. Previously, the land was all industrial. The peak flow could realistically be considered to
happen at the same time for the entire zone since it was all of the same type. However, residential
and industrial peak flows do not realistically happen at the same time. Residential zones have two
peaks during the day. There is an initial peak early in the morning as people are getting ready to start
the day, and a second peak in the evening after people return home from work. Industrial peaks
occur during the day while people are at work. Although it does not show in the peak flow analysis,
the realistic delta between the original peak flow (0.78 MGD, 1.20 cfs) and the new peak flow (0.68
MGD, 1.18 cfs) will be even greater than the projected 0.10 MGD (0.15 cfs) because of the time
differences of when the peaks occur for the different zone types.
Reduction
(With Oil Field)
(MGD)(MGD)% Change (MGD)% Change (MGD)% Change % Change
0.17 0.68 292%0.76 340%0.78 349%-2%
No
Development (With Oil Field)(No Oil Field)(With Oil Field)
System Deltas
Location Developed - Current Zoning Developed - Original Zoning
Akers Rd S of White Ln
Single-Family
(dwellings)
Multi-Family
(dwellings)
Industrial
(acres)
Acreage
(acres)
Peak Design
Flow (MGD)
Peak Design
Flow (cfs)
R1 194 3.42
R2 396 22.87 3.27
M1 8.95 8.95 2.00 0.09 0.13
M2 19.25 19.25 2.00 0.19 0.29
Oil Drill 8.61 0 0.00
Akers Rd 2.53 0 0.00
totals 194 396 28.20 62.21 3.12 0.68 1.05
0.63
Current Zoning, Single-Family Residential Included, Oil Field Excluded
0.40
13
A summary of the 10” pipe flow characteristics can be seen in Table 7.
Table 7 – Akers 10” Pipe
Field Study
The data from the water flow loggers shows the depth of flow in the pipes to be very similar during the
weekdays (M-F). The flow rises quickly in the mornings (morning residential peak), stays relatively
constant throughout the day (bolstered by industrial peak), and begins to rise again in the evening
(second residential peak), peaking late at night before falling quickly during the early hours of the next
morning. (see Figures 8-12 for flow charts) Saturday’s flow peaks around the mid-morning, and falls
fairly steadily until late at night, where it drops off rapidly to its low point early Sunday morning. Sunday
is slightly different from Saturday, but only in that there is a second, but smaller peak, in the flow late at
night.
Noticing that the flow rates each day seemed to follow a pattern, we decided to visually check the flow
rates during their expected peak times. For seven days straight, we went to each site and physically
measured the depth of flow during the expected peak times (times based on the data from the flow
meters). We took measurements during the week at all five locations between 10pm and 12am. On
Saturday and Sunday we took measurements between 11am and 1pm, but only at Stine/McCutchen,
McCutchen/Breccia, and McCutchen/Ashe. For two days during the week, in addition to their nightly
checks, we also checked these last three sites between 10am and 12pm.
These manual readings confirmed what the data from the water flow loggers was telling us. The pipes
were not nearly full. The pipe at McCutchen and Ashe was never more than 56% full during these
readings. The pipe at McCutchen and Breccia was never more than 58% full during these readings. The
pipe at Stine and McCutchen was never more than 60% full during these readings. The pipe at Stine
and Panama was never more than 67% full during these readings. Finally, the pipe at Stine and Harris
was never more than 65% full during these readings. (See Table 8)
*Note: Max flow through the pipe does not occur when it is 100% full. Max flow occurs at around
93.8% full. This is why a depth of 24” in a 48” pipe is considered more than 50% full in the table below.
(MGD)% Fill (MGD)% Fill (MGD)% Fill (MGD)% Fill (MGD)% Fill
0.17 28%0.68 111%0.76 125%0.78 127%0.61 100%
No Development
Current Zoning
(no Oil)
Current Zoning
(with Oil)
Original Zoning
(Full Parcel)10" Pipe Capacity
Akers' 10" Pipe - Flow Characteristics
14
Field Study Manual Readings
Table 8
Further confirmation of the data occurred through happenstance. One day, during the manual
readings, a piece of our measuring paper was accidentally dropped into the sewer. It happened to
land on a ledge that sits a little more than half way up the side of the pipe (see Figure 13). That piece
of paper was still there two days later when we took our final reading. Had the water risen up to this
ledge, the paper would have easily been swept away.
Using the peak flow analysis of the system, we calculated how much additional flow there would be in
the system at major points downstream of our site, including the points at which we were measuring
the water flow levels in the sewer pipes. (See Table 9. Sysem flow calculations, such as those found in
Table 9, come from Sewer System Peak Flow Calculations starting on page 43.)
Depth % Full Depth % Full
Fri Fri 5/1/2015 11:55 PM 12"47%
Sat 5/2/2015 12:24 AM 12"47%Sat
Sun Sun
Mon 5/4/2015 10:06 PM 13"51%Mon 5/4/2015 10:47 PM 14"55%
Tues 5/5/2015 9:01 PM 16"63%Tues 5/5/2015 9:47 PM 15"59%
Wed 5/6/2015 10:14 PM 17.5"69%Wed 5/6/2015 10:52 PM 15"59%
Thurs 5/7/2015 9:38 PM 17"67%Thurs 5/7/2015 10:14 PM 18"71%
Depth % Full Depth % Full
Fri 5/1/2015 11:33 PM 18"64%Fri 5/1/2015 11:20 PM 18"53%
Sat 5/2/2015 12:30 PM 17"60%Sat 5/2/2015 12:10 PM 20"59%
Sun 5/3/2015 12:43 PM 18"64%Sun 5/3/2015 12:34 PM 20"59%
Mon 5/4/2015 11:13 PM 17.5"62%Mon 5/4/2015 11:23 PM 19"56%
Tues 5/5/2015 10:11 PM 18"64%Tues 5/5/2015 10:31 PM 19"56%
Wed 5/6/2015 10:36 AM 15.5"55%Wed 5/6/2015 10:46 AM 17.5"52%
Wed 5/6/2015 11:35 PM 17"60%Wed 5/6/2015 11:45 PM 18"53%
Thurs 5/7/2015 11:18 AM 15.5"55%Thurs 5/7/2015 11:26 AM 17.5"52%
Thurs 5/7/2015 10:42 PM 18"64%Thurs 5/7/2015 11:15 PM 21"62%
Stine N of McCutchen (30")
Stine N of Harris (27")
McCutchen and Breccia (36")
Stine N of Panama (27")
Depth % Full
Fri 5/1/2015 10:54 PM 21"47%
Sat 5/2/2015 11:58 AM 24"53%
Sun 5/3/2015 12:21 PM 23"51%
Mon 5/4/2015 11:36 PM 27"60%
Tues 5/5/2015 10:42 PM 26"58%
Wed 5/6/2015 11:56 PM 25"56%
Thurs 5/7/2015 11:15 PM 21"47%
McCutchen W of Ashe (48")
15
Table 9 – System Deltas
Combining these calculations with the maximum depth of flow as measured by the water flow loggers
(See Table 10), the additional flow in the system we will create by developing our rezoned parcel will
increase the depth of flow in the pipe on Stine Rd north of Harris Rd from 76% full to 78% full at its peak
(79% with the oil field included). It will increase the depth of flow in the pipe on Stine Rd north of
Panama Ln from 79% full to 82% full at its peak (82% with the oil field). It will increase the depth of flow
in the pipe on Stine Rd north of McCutchen Rd from 79% full to 81% full at its peak (81% with the oil
field). It will increase the depth of flow in the pipe at McCutchen Rd and Breccia Way from 64% full to
65% full at its peak (65% with oil field). It will increase the depth of flow in the pipe on McCutchen Rd
west of Ashe Rd from 74% full to 75% full at its peak (75% with the oil field).
Table 10 – Pipe Capacities
Conclusion
After extensive field inspections and monitoring as well as analysis of the existing sewer system, it is our
professional opinion that the existing sewer system design is more than adequate for its intended use.
The locations we observed do not exhibit a sudden peak, as would be suggested by the peaked flow
model. Rather, they seem to experience a prolonged peak. The flow in the pipe at Stine and Harris was
above 80% of its maximum daily peak flow rate for more than 12 hours per day. As you look at the pipes
getting closer and closer to the sewage treatment plant, this time period gets even longer. Some of this
prolonged peaking can be attributed to the length of the lines connected to the plant. With the
distances to the treatment plant being anywhere from less than a mile to over seven miles away, the
sewage does not all reach the plant at the same time. In fact, the time it reaches the plant varies
Reduction
(With Oil Field)
(MGD)(MGD)% Change (MGD)% Change (MGD)% Change % Change
0.17 0.68 292%0.76 340%0.78 349%-2%
4.99 5.44 9%5.52 11%5.59 12.1%-11%
11.89 12.33 4%12.41 4%12.49 5.1%-14%
14.76 15.20 3%15.28 4%15.37 4.1%-14%
15.08 15.51 3%15.60 3%15.68 4.0%-14%
20.31 20.74 2%20.82 3%20.91 3.0%-15%
21.12 21.55 2%21.63 2%21.73 2.9%-15%
27.62 28.04 2%28.13 2%28.23 2.2%-16%
29.21 29.63 1%29.71 2%29.81 2.1%-17%
41.72 42.14 1%42.22 1%42.33 1.45%-17%
No
Development (With Oil Field)(No Oil Field)(With Oil Field)
System Deltas
Location Developed - Current Zoning Developed - Original Zoning
Akers Rd S of White Ln
White Ln and Akers
Stine Rd and White Ln
McCutchen Rd and Ashe Rd
Stine Rd N of Harris
Stine Rd N of Panama Ln
Stine Rd and McCutchen Rd
McCutchen Rd E of Ashe
Stine Rd and Panama Ln
Stine Rd N of McCutchen Rd
Excess Capacity
(in)(MGD)(MGD)% Fill (MGD)
18.58 4.63 6.09 76%1.46
19.21 4.84 6.09 79%1.25
21.31 7.36 9.28 79%1.92
21.87 8.35 13.11 64%4.77
32.37 18.11 24.46 74%6.35
McCutchen Rd and Breccia
McCutchen Rd and Ashe Rd
Stine Rd N of McCutchen Rd
Stine Rd N of Harris
Stine Rd N of Panama Ln
Sewer Pipe Fill and Capacity (as measuerd by the water flow loggers)
Location Maximum Depth of Flow Pipe Capacity
16
anywhere from ~30 minutes to over 5 hours from the time it enters the system (using an average
velocity of 2 ft/s). We feel this explains why the actual flow rates, as observed by the water flow
loggers, so poorly matches the calculated values, using the peaked flow model.
With regard to the field study, none of the five manholes we observed experienced a pressure flow
during any point of our study, nor did any of them have any signs of having previously experienced a
pressure flow (no water marks on the sides of the manhole tubes, see Figures 13-15). The opposite is
actually true. The field study shows that the pipes actually have plenty of room for more flow.
According to our field results, the Stine and Panama pipe has the least excess capacity of those in the
study, and this pipe still has room for an additional 1.25 MGD (1.93 cfs) at its peak. (See Table 10)
The main takeaway from our analysis is as follows: by replacing a section of the parcel with apartments
instead of fully developing it as an industrial complex, we are actually reducing the originally designed
demand on the sewer system as a whole (see Table 9). As the sewage progresses down the system, this
delta will continue to grow because the residential peak factor will decrease as more units are added to
the system, but no such diminishing factor exists for industrial zones. The peak factor is always 2.0 for
industrial areas, but is constantly becoming smaller than 5.8 for residential zones as more and more
residential units are added to the system.
Based upon our analysis, combined with the field study, the existing sewer system has the available
capacity to accommodate the proposed development and is adequate for its proposed use.
17
Figure 6a – Sewer Zoning and Pipe Size Legend
18
Figure 6b – Sewer Lines and Test Locations
19
Figure 6c – Sewer Lines with Zoning Information
20
Figure 7a – Stine Sewer Lines
21
Figure 7b – Akers S of White Ln Sewer System
22
Figure 7c – Akers S of White Ln Detailed Area (Project Site and Single-Family Residential)
23
Figure 7d – White Ln E of Akers Sewer System
24
Figure 7e – Akers N of White Ln Sewer System
25
Figure 7f – Stine N of White Ln Sewer System
26
Figure 7g – White Ln E of Stine Sewer System
27
Figure 7h – Stine and Pacheco Sewer System
28
Figure 7i – Harris and Stine Sewer System
29
Figure 7j – Panama and Stine Sewer System
30
Figure 7k – Stine N of McCutchen Sewer System
31
Figure 7l – Hosking Sewer Lines
32
Figure 7m – McCutchen Sewer Lines
33
Figure 7n – Ashe Sewer Lines
34
Figure 8 – Stine Harris (27”)
35
Figure 9 – Stine and Panama (27”)
36
Figure 10 – Stine and McCutchen (30”)
37
Figure 11 – McCutchen and Breccia (36”)
38
Figure 12 – McCutchen and Ashe (48”)
*The anomaly between days 10 and 11 is a period of time we had the system out of the sewers, inspecting the setup and changing batteries.
39
Figure 13 – Paper on the Ledge (Stine Rd N of McCutchen Manhole Tube)
40
Figure 14 – McCutchen and Breccia Manhole Tube
41
Figure 15 – McCutchen and Ashe Manhole Tube
42
Sewer System Peak Flow Calculations
All of the following calculations include the oil field, even though we do not plan to connect it to the sewer system. See
the figure listed in each table’s title to visually see what areas are contained within each calculation.
Zone Area (sqft)# of Apts.# of Houses
Commercial Area
(sqft)
industrial Area
(sqft)Persons Peak Factor
Design Flow
(MGD)
R1 194 504.40
R2 -
M1/M2 2,709,868 0.30
- 194 - 2,709,868 504 0.78
3.42
totals
Akers Rd S of White Ln - Original Zoning (Figure 2b)
0.17
Zone Area (sqft)# of Apts.# of Houses
Commercial Area
(sqft)
industrial Area
(sqft)Persons Peak Factor
Design Flow
(MGD)
R1 194 504 3.42
R2 996,217 396.00 792 3.27
M1 389,737 0.04
M2 838,655 0.09
M2 375,052 0.04
396 194 - 1,603,444 1,296 3.12 0.76 totals
Akers Rd S of White Ln - Current Zoning (Figure 2b)
0.40
Zone Area (sqft)# of Apts.# of Houses
Commercial Area
(sqft)
industrial Area
(sqft)Persons Peak Factor
Design Flow
(MGD)
R1 241 627 3.35
R2 173,425 69.37 139 3.90
R3 73,645 58.92 118 3.96
M1MH 112 291 3.62
PUD (apt.)994,074 397.63 795 3.27
M1 3,871,270 0.43
M2 1,007,880 0.11
C1 300,513 0.02
C2 775,666 0.06
526 353 1,076,179 4,879,150 1,970 2.99 1.83
0.59
White Ln E of Akers Rd - Original Zoning (Figure 2d)
totals
43
Zone Area (sqft)# of Apts.# of Houses
Commercial Area
(sqft)
industrial Area
(sqft)Persons Peak Factor
Design Flow
(MGD)
R1 241 627 3.35
R2 173,425 69.37 139 3.90
R3 73,645 58.92 118 3.96
M1MH 112 291 3.62
PUD (apt.)994,074 397.63 795 3.27
M1 3,871,270 0.43
M2 1,007,880 0.11
C1 300,513 0.02
C2 775,666 0.06
526 353 1,076,179 4,879,150 1,970 2.99 1.83 totals
White Ln E of Akers Rd - Current Zoning (Figure 2d)
0.59
Zone Area (sqft)# of Apts.# of Houses
Commercial Area
(sqft)
industrial Area
(sqft)Persons Peak Factor
Design Flow
(MGD)
R1 1600 4160 2.77
R2 1,846,933 738.77 1,478 3.08
R3 2,341,508 1,873.21 3,746 2.80
RS 43 111.8 3.98
R1CH 230,590
R2CH 137,998
R2P 11,408
C1 860,000 0.07
C2 3,460,448 0.29
PCD 264,736 0.02
CO 503,060 0.04
P 8,844
2,612 1,643 5,088,244 - 9,496 2.55 3.18
Akers Rd N of White Ln - Original Zoning (Figure 2e)
2.42
totals
44
Zone Area (sqft)# of Apts.# of Houses
Commercial Area
(sqft)
industrial Area
(sqft)Persons Peak Factor
Design Flow
(MGD)
R1 1600 4160 2.77
R2 1,846,933 738.77 1,478 3.08
R3 2,341,508 1,873.21 3,746 2.80
RS 43 111.8 3.98
R1CH 230,590
R2CH 137,998
R2P 11,408
C1 860,000 0.07
C2 3,460,448 0.29
PCD 264,736 0.02
CO 503,060 0.04
P 8,844
2,612 1,643 5,088,244 - 9,496 2.55 3.18 totals
2.42
Akers Rd N of White Ln - Current Zoning (Figure 2e)
Zone Area (sqft)# of Apts.# of Houses
Commercial Area
(sqft)
industrial Area
(sqft)Persons Peak Factor
Design Flow
(MGD)
R1 2146 5579.6 2.69
R2 3,293,701 1,317.48 2,635 2.90
R3 4,329,608 3,463.69 6,927 2.63
RS 24 62 4.22
R2MH 227 590 3.37
PUD (house)76.00 198 3.76
PUD (apt.)1,433,968 573.59 1,147 3.15
R1CH 1,440,329
R1P 16,231
R2P 10,579
M1 2,339,459 0.26
C1 766,079 0.06
C2 9,144,375 0.75
PCD 2,427,612 0.20
CO 4,653,972 0.38
P 6,483
OS 1,392,081
5,355 2,473 16,992,038 2,339,459 17,139 2.41 7.17
Stine Rd N of White Ln - Original Zoning (Figure 2f)
totals
4.13
45
Zone Area (sqft)# of Apts.# of Houses
Commercial Area
(sqft)
industrial Area
(sqft)Persons Peak Factor
Design Flow
(MGD)
R1 2146 5579.6 2.69
R2 3,293,701 1,317.48 2,635 2.90
R3 4,329,608 3,463.69 6,927 2.63
RS 24 62 4.22
R2MH 227 590 3.37
PUD (house)76.00 198 3.76
PUD (apt.)1,433,968 573.59 1,147 3.15
R1CH 1,440,329
R1P 16,231
R2P 10,579
M1 2,339,459 0.26
C1 766,079 0.06
C2 9,144,375 0.75
PCD 2,427,612 0.20
CO 4,653,972 0.38
P 6,483
OS 1,392,081
5,355 2,473 16,992,038 2,339,459 17,139 2.41 7.17
Stine Rd N of White Ln - Current Zoning (Figure 2f)
totals
4.13
Zone Area (sqft)# of Apts.# of Houses
Commercial Area
(sqft)
industrial Area
(sqft)Persons Peak Factor
Design Flow
(MGD)
R1 282 733.20
R2 335,915 134.37 268.73
134 282 - - 1,002 0.32
3,668 2,472 6,164,423 6,482,594 13,764 2.46 5.74
3.20
White Ln E of Stine Rd - Current Zoning (Figure 2g)
totals
Total Sum
0.32
Zone Area (sqft)# of Apts.# of Houses
Commercial Area
(sqft)
industrial Area
(sqft)Persons Peak Factor
Design Flow
(MGD)
R1 282 733.20
R2 335,915 134.37 268.73
134 282 - - 1,002 0.32
3,272 2,472 6,164,423 7,589,018 12,972 2.47 5.81
White Ln E of Stine Rd - Original Zoning (Figure 2g)
0.32 3.20
totals
Total Sum
46
Zone Area (sqft)# of Apts.# of Houses
Commercial Area
(sqft)
industrial Area
(sqft)Persons Peak Factor
Design Flow
(MGD)
M1MH 28.00 72.80 4.16 0.03
M1 2,147,388 2.27 0.24
M2 567,402 0.06
- 28 - 2,714,790 73 4.16 0.63
8,627 4,973 23,156,461 12,643,267 30,184 2.27 13.11
Stine Rd and Pacheco Rd - Original Zoning (Figure 2h)
totals
Total Sum
Zone Area (sqft)# of Apts.# of Houses
Commercial Area
(sqft)
industrial Area
(sqft)Persons Peak Factor
Design Flow
(MGD)
M1MH 28.00 72.80 4.16 0.03
M1 2,147,388 0.24
M2 567,402 0.06
- 28 - 2,714,790 73 4.16 0.63
9,023 4,973 23,156,461 11,536,843 30,976 2.27 13.03
Stine Rd and Pacheco Rd - Current Zoning (Figure 2h)
totals
Total Sum
Zone Area (sqft)# of Apts.# of Houses
Commercial Area
(sqft)
industrial Area
(sqft)Persons Peak Factor
Design Flow
(MGD)
R1 785 2,041 2.98
R2 155,972 62.39 125 3.94
R3 48,939 39.15 78 4.13
RS 377 980 3.20
MH 199 517 3.42
M1 2,487,421 0.28
M2 3,595,523 0.40
C1 187,525 0.02
PCD 748,805 0.06
P 17,232
A 1,499,248
OS 225,766
102 1,361 936,330 6,082,944 3,742 2.80 2.54
8,729 6,334 24,092,791 18,726,211 33,926 2.25 15.37
Harris Rd & Stine Rd - Original Zoning (Figure 2i)
totals
Total Sum
1.05
47
Zone Area (sqft)# of Apts.# of Houses
Commercial Area
(sqft)
industrial Area
(sqft)Persons Peak Factor
Design Flow
(MGD)
R1 785 2,041 2.98
R2 155,972 62.39 125 3.94
R3 48,939 39.15 78 4.13
RS 377 980 3.20
MH 199 517 3.42
M1 2,487,421 0.28
M2 3,595,523 0.40
C1 187,525 0.02
PCD 748,805 0.06
P 17,232
A 1,499,248
OS 225,766
102 1,361 936,330 6,082,944 3,742 2.80 2.54
9,125 6,334 24,092,791 17,619,787 34,718 2.24 15.28
Harris Rd & Stine Rd - Current Zoning (Figure 2i)
totals
Total Sum
1.05
Zone Area (sqft)# of Apts.# of Houses
Commercial Area
(sqft)
industrial Area
(sqft)Persons Peak Factor
Design Flow
(MGD)
R1 4477 11,640 2.50
R2 2,408,870 963.55 1,927 2.99
R3 124,391 99.51 199 3.76
RS 58 151 3.86
MH 426 1,108 3.17
PUD (house)412 1,071 3.18
M1 5,021,832 0.56
C1 1,149,175 0.09
C2 4,738,659 0.39
PCD 2,356,602 0.19
CO 110,481 0.01
A 48,334
OS 217,940
1,063 5,373 8,354,917 5,021,832 16,096 2.42 6.26
9,792 11,707 32,447,708 23,748,043 50,021 2.16 20.91
totals
Total Sum
3.90
Panama Ln & Stine Rd - Original Zoning (Figure 2j)
48
Zone Area (sqft)# of Apts.# of Houses
Commercial Area
(sqft)
industrial Area
(sqft)Persons Peak Factor
Design Flow
(MGD)
R1 4477 11,640 2.50
R2 2,408,870 963.55 1,927 2.99
R3 124,391 99.51 199 3.76
RS 58 151 3.86
MH 426 1,108 3.17
PUD (house)412 1,071 3.18
M1 5,021,832 0.56
C1 1,149,175 0.09
C2 4,738,659 0.39
PCD 2,356,602 0.19
CO 110,481 0.01
A 48,334
OS 217,940
1,063 5,373 8,354,917 5,021,832 16,096 2.42 6.26
10,188 11,707 32,447,708 22,641,619 50,813 2.16 20.82
totals
Total Sum
Panama Ln & Stine Rd - Current Zoning (Figure 2j)
3.90
Zone Area (sqft)# of Apts.# of Houses
Commercial Area
(sqft)
industrial Area
(sqft)Persons Peak Factor
Design Flow
(MGD)
R1 458 1,191 3.14
R2 2,468,720 987.49 1,975 2.99
R3 242,030 193.62 387 3.52
PUD 167,152 -
R1CH 785,191
C2 828,489 0.07
1,181 458 828,489 - 3,553 2.82 1.12
10,973 12,165 33,276,197 23,748,043 53,574 2.15 21.73
Stine Rd North of McCutchen Rd - Original Zoning (Figure 2k)
totals
Total Sum
1.00
49
Zone Area (sqft)# of Apts.# of Houses
Commercial Area
(sqft)
industrial Area
(sqft)Persons Peak Factor
Design Flow
(MGD)
R1 458 1,191 3.14
R2 2,468,720 987.49 1,975 2.99
R3 242,030 193.62 387 3.52
PUD 167,152 -
R1CH 785,191
C2 828,489 0.07
1,181 458 828,489 - 3,553 2.82 1.12
11,369 12,165 33,276,197 22,641,619 54,366 2.14 21.63
Stine Rd North of McCutchen Rd - Current Zoning (Figure 2k)
totals
Total Sum
1.00
Zone Area (sqft)# of Apts.# of Houses
Commercial Area
(sqft)
industrial Area
(sqft)Persons Peak Factor
Design
Flow
(MGD)
R1 6350 16,510.00 2.42
R2 3,256,094 1,302.44 2,604.88 2.91
R3 368,535 294.83 589.66 3.37
RS 234 608.40 3.36
E 466 1,211.60 3.14
MH 498,885 -
R110K 368 956.80 3.21
RS1A 50 130.00 3.92
RS2.5A 10 26.00 4.61
E1A 58,193 3 7.80 5.20
PUD (apt)811,501 324.60 649.20 3.34
R1CH 1,550,503
M1 605,366 0.07
M2 866,629 0.10
C1 407,568 0.03
C2 11,425,181 0.94
A 10,894,208
OS 440,494
1,922 7,481 11,832,749 1,471,995 23294 2.33 7.52
12,895 19,646 45,108,946 25,220,038 76869 2.07 28.23
5.44
totals
Total Sum
Hosking/McCutchen and Stine - Original Zoning (Figure 2l)
50
Zone Area (sqft)# of Apts.# of Houses
Commercial Area
(sqft)
industrial Area
(sqft)Persons Peak Factor
Design
Flow
(MGD)
R1 6350 16,510.00 2.42
R2 3,256,094 1,302.44 2,604.88 2.91
R3 368,535 294.83 589.66 3.37
RS 234 608.40 3.36
E 466 1,211.60 3.14
MH 498,885 -
R110K 368 956.80 3.21
RS1A 50 130.00 3.92
RS2.5A 10 26.00 4.61
E1A 58,193 3 7.80 5.20
PUD (apt)811,501 324.60 649.20 3.34
R1CH 1,550,503
M1 605,366 0.07
M2 866,629 0.10
C1 407,568 0.03
C2 11,425,181 0.94
A 10,894,208
OS 440,494
1,922 7,481 11,832,749 1,471,995 23294 2.33 7.52
13,291 19,646 45,108,946 24,113,614 77661 2.07 28.13
totals
Total Sum
5.44
Hosking/McCutchen and Stine - Current Zoning (Figure 2l)
51
Zone Area (sqft)# of Apts.# of Houses
Commercial Area
(sqft)
industrial Area
(sqft)Persons Peak Factor
Design Flow
(MGD)
R1 1,740 4,524.00 2.75
R2 1,129,768 452 903.81 3.23
RS 43,379 1 2.60 5.80
M1 1,745,251 0.19
C1 1,258,925 0.10
A 4,336,630
OS 261,091
totals 452 1,741 1,258,925 1,745,251 5,430 2.70 2.04
13,347 21,387 46,367,871 26,965,289 82,299 2.06 29.81
1.47
Total Sum
McCutchen Rd East of Ashe Rd - Original Zoning (Figure 2m)
Zone Area (sqft)# of Apts.# of Houses
Commercial Area
(sqft)
industrial Area
(sqft)Persons Peak Factor
Design Flow
(MGD)
R1 1,740 4,524.00 2.75
R2 1,129,768 452 903.81 3.23
RS 43,379 1 2.60 5.80
M1 1,745,251 0.19
C1 1,258,925 0.10
A 4,336,630
OS 261,091
totals 452 1,741 1,258,925 1,745,251 5,430 2.70 2.04
13,743 21,387 46,367,871 25,858,865 83,091 2.06 29.71 Total Sum
1.47
McCutchen Rd East of Ashe Rd - Current Zoning (Figure 2m)
52
Zone Area (sqft)# of Apts.# of Houses
Commercial Area
(sqft)
industrial Area
(sqft)Persons Peak Factor
Design Flow
(MGD)
R1 7518 19,546.80 2.38
R2 12,201,184 4,880.47 9,760.95 2.55
R3 5,503,924 4,403.14 8,806.28 2.57
E 275 715.00 3.31
PUD (house)383 995.80 3.20
PUD (apt)209,292 83.72 167.43 3.82
R1CH 829,042
R3CH 119,370
M1 8,808,617 0.98
M2 10,985,421 1.22
C1 875,513 0.07
C2 2,279,998 0.19
PCD 638,886 0.05
CO 2,013,355 0.17
RE 186,009
OS 10,605,600
9,367 8,176 5,807,752 19,794,038 39992 2.21 14.11
22,714 29,563 52,175,623 46,759,327 122291 1.98 42.33
8.84
Totals
Total Sum
Ashe Rd - Original Zoning (Figure 2n)
53
Zone Area (sqft)# of Apts.# of Houses
Commercial Area
(sqft)
industrial Area
(sqft)Persons Peak Factor
Design Flow
(MGD)
R1 7518 19,546.80 2.38
R2 12,201,184 4,880.47 9,760.95 2.55
R3 5,503,924 4,403.14 8,806.28 2.57
E 275 715.00 3.31
PUD (house)383 995.80 3.20
PUD (apt)209,292 83.72 167.43 3.82
R1CH 829,042
R3CH 119,370
M1 8,808,617 0.98
M2 10,985,421 1.22
C1 875,513 0.07
C2 2,279,998 0.19
PCD 638,886 0.05
CO 2,013,355 0.17
RE 186,009
OS 10,605,600
9,367 8,176 5,807,752 19,794,038 39992 2.21 14.11
23,110 29,563 52,175,623 45,652,903 123083 1.98 42.22
Totals
Total Sum
8.84
Ashe Rd - Current Zoning (Figure 2n)
54
Appendix A
55