CHAPTER 3 Model Development

Full text

(1)CHAPTER 3 Model Development The computer-based hydraulic sewer model of the City’s wastewater collection system serves as a tool for assessing the flows and capacities of the City’s major sewers, for identifying solutions to potential capacity issues, and for performing what-if scenarios to assess the impacts of future development, land use changes, and system configuration changes. The model makes use of dynamic Innovyze® InfoSewer™ software that allows for a time-varying flow analysis of dry weather and peak wet weather conditions. The development of the collection system model involves consideration of the following topics: •. Modeled Facilities. •. Capacity Evaluation. •. Model Flow Quantities. •. Model Calibration. •. Modeled Time Frame Scenarios. 3.1 MODELED FACILITIES. The modeled collection system facilities are depicted on Figure 3-1 for existing conditions and on Figure 3-2 for buildout conditions. In general, the modeled facilities include all 12-inch diameter and larger trunk lines and associated lift stations, as well as smaller diameter lines in selected areas. The model includes the existing lift station (LS) facilities summarized in Table 3-1. Table 3-1. Parameters for Modeled Existing Lift Station. Number of Pumps. Pump Speed. Firm Capacity, mgd(a). Force Main Diameter, in. Force Main Length, in(b). Allison Parkway. 2. Fixed. 0.79. 8. 394. B Street. 2. Fixed. 0.51. 4. 47. Brown Street. 4. Variable. 1.3. 8. 138. Grandview. 2. Fixed. 0.083. 2. 128. Horse Creek. 4. Variable. 2.3. 18. 839. Leisure Town Road. 4. Variable. 7.2. 18 & 12. 3,288. Vaca Valley Parkway. 4. Variable. 3.7. 14. 410. Lift Station. (a). Assumes the largest unit out of service, and with no duty pumps operating (variable speed stations only). Pump capacities were obtained as follows: • Allison Parkway: Based on draw and fill tests performed on March 31, 2010. • B Street: Based on pump run time data from the 2016/2017 wet season. • Brown Street: Based on Project Manual for Brown Street Lift Station, dated July 2014. • Grandview LS: Based on draw and fill tests performed on April 30, 2008. • Horse Creek: Based on pump nameplate ratings. • Leisure Town Road: Based on pump nameplate ratings. • Vaca Valley Parkway: Based on pump nameplate ratings.. (b). All force main lengths taken from the City’s sewer map (CAD format), December 2015, except for the Brown Street LS force main, which is taken from Plans for Brown Street Lift Station (December 2014), page C-4.. March 2018. n\c\001\21-15-61\WP\WWCSMP Report\060616_Ch 3. 3-1. City of Vacaville Wastewater Facilities Master Plan.

(2) Chapter 3 Model Development Gravity sewer diameters are taken from a combination of record drawings and City mapping information. Gravity sewer depths and invert and rim elevations are based on a combination of field survey data (discussed in Chapter 2) and City record drawings. Lift station geometries, set points, and capacities are based upon existing City record drawings and/or design documents. Each manhole in the model is defined as a node, and each pipe is defined as a link. The model flow inputs occur at the model nodes. The model then calculates cumulative flows for each link and the hydraulic grade line elevations at each node. Because the City land use database is parcel-based, each flow-producing land use parcel must be assigned to a given node. The assignment of parcels is accomplished through the use of sewershed areas, which represent the effective sewer tributary area associated with a given node. The sewershed areas are shown on Figure 3-3 for existing conditions and on Figure 3-4 for buildout conditions. For simplicity and conservatism, not all nodes have associated sewersheds. Instead the parcels associated with a given sewer reach are lumped together into a single sewershed and then assigned to an upstream node on that reach. (For discussion purposes, the term “sewer reach” is defined as a series of pipes and manholes where the pipe diameter does not change, and within which no major flow confluences occur.) 3.2 CAPACITY EVALUATION. The purpose of the collection system modeling analysis is to evaluate current and future capacity needs with regard to gravity mains, lift stations and force mains. Accordingly, the following topics are discussed in this section: •. Qp versus Qd. •. Capacity Evaluation Criteria. 3.2.1 Qp versus Qd. The process of evaluating system capacity involves the analysis of two types of peak flow conditions: peak wet weather flow (Qp) and a design flow (Qd). Qp represents the theoretical maximum flow that would occur in the collection system during a major storm event. Qd represents a flow condition that serves as the basis for designing new collection system facilities. The Qd analysis is more relevant to buildout conditions than to existing conditions because buildout flows are generally the basis for the design of any new facilities. The exact calculations and procedures for determining Qp and Qd are discussed in Section 3.3. 3.2.2 Capacity Evaluation Criteria. In performing a system capacity evaluation, specific criteria need to be applied to each type of facility: gravity mains, lift stations and force mains. In the case of lift stations, the key criterion is that all stations need to be able to handle Qp and Qd conditions with the largest pump out of service. In the case of force mains, flow velocities should not exceed 10 feet per second for either Qp and Qd conditions. March 2018. n\c\001\21-15-61\WP\WWCSMP Report\060616_Ch 3. 3-2. City of Vacaville Wastewater Facilities Master Plan.

(3) Chapter 3 Model Development The evaluation of gravity mains is somewhat more complex than for lift stations and force mains. In the case of gravity mains, it is generally considered acceptable for there to be a limited amount of surcharging in the line under Qp conditions, provided that any such surcharging does not reach an elevation that is within 8 feet of the manhole rim. (Surcharging is defined as a flow condition in which the hydraulic grade line is above the crown of the pipe.) For modeling purposes, excessive surcharging is defined as follows: 1. For manholes where the pipe crown is more than 8 feet deep, surcharging to within 8 feet of the ground surface is considered excessive. 2. For manholes where the pipe crown is less than 8 feet deep, surcharging of more than 0.1 feet above the pipe crown is considered excessive. Under Qd conditions, the maximum flow rate in the line cannot exceed the so-called 70/80/90 criteria, defined as follows: •. Qd ≤ 70 percent of full-pipe capacity for sewers of 10-inch diameter or less. •. Qd ≤ 80 percent of full-pipe capacity for sewers of between 12 and 18-inch diameter. •. Qd ≤ 90 percent of full-pipe capacity for sewers of 21-inch diameter or larger. Accordingly, any future gravity flow sewers (whether replacement sewers in existing development areas or new sewers serving growth areas) must be designed such that the buildout Qd flow conforms to the 70/80/90 criteria. 3.3 MODEL FLOW QUANTITIES. For the purposes of collection system modeling, the following flow elements are of interest: • • • •. Average Dry Weather Flow Dry Weather Flow Variation I&I Qp and Qd Calculation. 3.3.1 Average Dry Weather Flow. The term average dry weather flow (Qa) is intended to represent average sewer flow conditions in the collection system when I&I is minimal. The two major components of the Qa calculation include standard base flow and special case flow. 3.3.1.1 Standard Base Flow. The model makes use of existing City collection system flow factors that define Qa on a per unit basis by land use type. The collection system flow factors in units of gallons per day (gpd) per unit of land use for existing and future land uses are summarized in Table 3-2. As indicated in the table, most of the flow factors are in units of flow per acre. The exceptions are residential land uses, which are expressed in units of flow per dwelling unit (du), and elementary and high school land uses, which are expressed in units of flow per student. March 2018. n\c\001\21-15-61\WP\WWCSMP Report\060616_Ch 3. 3-3. City of Vacaville Wastewater Facilities Master Plan.

(4) Chapter 3 Model Development Table 3-2. City Land Use-Based Collection System Flow Factors Unit Flow, gpd/unit. (a). (b). (c). Land Use Category. Unit. Existing+Approved Development(a). Future Development(b). Residential. du. 200. 240. Elementary School. student. 20. 25. High School. student. 25. 30. Agriculture. acre. 0. 0. Church(c). acre. 1,600. 1,900. Commercial Highway. acre. 4,000. 5,000. Commercial Office. acre. 1,200. 1,500. Commercial Service. acre. 1,600. 1,900. Downtown. acre. 4,000. 5,000. Hospital(c). acre. 4,000. 4,000. Industrial. acre. 1,200. 2,000. Medical Office. acre. 4,000. 4,000. Open Space. acre. 0. 0. Private Recreation. acre. 1,200. 1,500. Public High. acre. 1,200. 1,500. Public Low. acre. 0. 0. Public Medium. acre. 1,200. 1,500. Public Park. acre. 0. 0. Retail Service. acre. 1,600. 1,900. Flow factors applied to existing development are subject to downward adjustment based on applicable flow metering data, as discussed later in this chapter (see Model Calibration). Future development flow factors are generally on the order of 20 percent high than existing factors to reflect uncertainty about the actual scale of future development. Previously, the City used a combined “Hospitals/Places of Worship” land use category. It was later determined that these two categories should be separated, and that Hospitals should be considered to have the same flow-producing characteristics as Medical Offices. It was determined that minimum value of 4,000 gpd/acre should be used for these two categories (Hospital and Medical Office), with the understanding that because this value is considered conservative, the usual 20 percent safety factor is not needed for the Future Development factor. It is recommended, however, that sitespecific flow estimates should be used to determine whether a value higher than the stated minimum is applicable.. The two major types of development in Table 3-2 include existing plus approved development and future development. Existing plus approved development refers to all existing development plus any future development that has already gone through the City approval process, such that the numbers of future units are set. Future development applies to areas that are not existing development and are not approved development projects. The higher flow factors for the future development category are intended to reflect the uncertainty of the scope of future planned development that has not gone through the City approval process.. March 2018. n\c\001\21-15-61\WP\WWCSMP Report\060616_Ch 3. 3-4. City of Vacaville Wastewater Facilities Master Plan.

(5) Chapter 3 Model Development There are two land uses specified in the City land use database for which flow factors have not previously been defined. These two land uses are Urban Reserve and Mixed Use, both of which only appear for buildout development conditions, not for existing development conditions. In the case of the Urban Reserve category, the land use database specifies residential dwelling units for certain parcels but not for others. For modeling purposes, it is assumed that parcels with dwelling units specified would produce flow based on the future residential flow factor of 240 gpd/du. For parcels with no dwelling units specified, it is assumed that the given parcels would produce flow at a rate of 1,900 gpd/acre, which reflects the buildout flow factor for the Service Commercial and Retail Service categories. In the case of the Mixed Use category, the land use database specifies residential dwelling units and also specifies a non-residential land use category in the secondary land use column. Accordingly, a future residential flow factor of 240 gpd/du is applied to the residential component, while the appropriate buildout flow factor is applied to the non-residential use. It should be noted that the application of the above flow factors to existing development results in an unadjusted Qa value, such that the calculated Qa will not necessarily produce results that match with existing flow data. Moreover, actual unit flows tend to change over time, most notably in recent years when unit flows have declined significantly from historical levels. The issue of the adjustment of dry weather flows to match collection system flow metering data is addressed later in this chapter (see Model Calibration). 3.3.1.2 Special Case Flows. Special case flows refer to flow sources for which the standard flow factors do not apply. This category is dominated by significant industrial dischargers, but also includes various other sources that are not represented by the City’s standard collection system flow factors. For existing conditions, special case flow sources are depicted schematically on Figure 3-5, and include: • • • • • • • • • • • • •. March 2018. Alza Corporation California Medical Facility (CMF) California State Prison – Solano (CSP-S) The unincorporated town of Elmira Gibson Canyon Creek (GCC) WWTP groundwater discharge Genentech Green Tree Golf Course Kaiser Permanente Mariani Packing Company Matheson Tri-Gas Save-Mart Distribution Center Solano Community College Vaca Valley Hospital. n\c\001\21-15-61\WP\WWCSMP Report\060616_Ch 3. 3-5. City of Vacaville Wastewater Facilities Master Plan.

(6) Chapter 3 Model Development These special case dischargers are also included in the buildout conditions model. In addition, for buildout conditions, several other special case areas are included in the analysis, all of which are defined in the NESSMP. These areas are depicted schematically on Figure 3-6, and include: •. Area A. •. Area B. •. Area E. •. Area E1. •. Area W. •. Laurelwood-Alza Transfer. •. Mission Area E (encompassing portions of Interchange Business Park). •. Vaca Valley Business Park. •. Vacaville Business Park (also called Vacaville-Golden Hills Business Park). The flows associated with the special case dischargers/areas for both existing and buildout conditions are summarized in Table 3-3. The existing conditions Qa values shown in Table 3-3 are intended to be reflective of flow conditions in fall 2013. This time frame was used to represent “existing conditions” because a significant drop-off in dry weather flows occurred thereafter, due to the severe drought conditions of 2014 and 2015. It is conservatively assumed that the observed drop-off in dry weather flows is not permanent, and that flows will tend to rebound during non-drought periods. For buildout conditions, special case discharges are generally assumed to equate to the maximum allowable rates of discharge. Accordingly, the following data and assumptions are used: 1. For CMF, CSP-S, and Genentech, the existing Qa is based on discharger flow data recorded in fall 2013 and taken from the City SCADA system. Buildout Qa values are assumed to equal the permitted maximum monthly average discharges in each case. For buildout conditions, the Genentech discharge is assumed to be split along two flow paths, as defined in the NESSMP. 2. For Alza, Mariani, Matheson Tri-Gas, and Save-Mart, the existing Qa is based on discharge flow data for the period of 2014-2015 provided by City staff. The flows do not show much variation and thus are assumed to be representative of the calibration period (fall 2013). Buildout Qa values are taken from the NESSMP. 3. For the GCC WWTP groundwater discharge, the existing Qa is based on discharge flow data provided by City staff. Buildout Qa values are assumed to equal the existing value. 4. For Kaiser Permanente and Vaca Valley Hospital, flows are estimated from water use data, as provided by City staff. Buildout Qa for Kaiser is as specified in the NESSMP. Buildout Qa for Vaca Valley Hospital is assumed to equal the permitted maximum monthly average discharge. March 2018. n\c\001\21-15-61\WP\WWCSMP Report\060616_Ch 3. 3-6. City of Vacaville Wastewater Facilities Master Plan.

(7) Chapter 3 Model Development Table 3-3. Modeled Special Case Discharge Qa Values Special Case Discharger/Area. Assumed Qa, gpd Existing. Buildout. Existing and Buildout Alza(a). 46,225. 89,700. CMF(b). 239,837. 642,895. CSP-S(b). 508,665. 854,000. 14,200. 52,340. 32,990. 32,990. 473,760. 715,000. 12,000. 12,000. 54,474. 142,200. 85,402. 150,000. 14,978. 23,000. 5,765. 134,779. 28,410. 42,615. 14,929. 50,000. --. 109,796. --. 314,282. Elmira(c) GCC WWTP. Groundwater(d). Genentech(b) Course(e). Green Tree Golf Kaiser. Permanente(f). Mariani(a) Matheson. Tri-Gas(a). Save-Mart (a) Solano. College(g). Vaca Valley. Hospital(f). Buildout Only Area A(h) Area. B(h). Area B released. capacity(h). --. 138,000. Area. E(h). --. 242,483. Area. E1(h). --. 100,776. Area. W (h). --. 82,431. --. 29,900. --. 83,797. --. 588,426. --. 754,771. Laurelwood-Alza Mission Area. Transfer(h). E(h). Vaca Valley Business Vacaville Business (a). (b) (c). (d) (e). (f) (g). (h). Park(h). Park(h). Discharge flow data covering the period of 2014–2015 were provided by City staff and are used as the basis for Qa calculations. Buildout Qa based on maximum allowance, as specified in the NESSMP. Existing Qa based on flow data taken from the City SCADA system. Buildout Qa assumed to equal the permitted average flow limit. Existing Qa based on lift station flow data from December 2016. Buildout Qa based on assumptions of 85 connected residential units, 3.7 acres of service commercial flows, and 284 elementary school students, per previous planning assumptions. Existing and buildout Qa based on discharge flow data provided by City staff. The golf course is closed; flows from that 165-acre area are assumed to be zero for existing conditions. For buildout conditions, a Qa of 12,000 gpd is assumed, based on an assumption that the golf course will reopen at some, and given that the 165-acre area is designated as Private Recreation in the City land use database. Golf course flow represents clubhouse activities, assumed equivalent to 10-acres of commercial activities. Existing Qa based on water use data provided by City staff. Buildout Qa assumed to equal the permitted average flow limit. Existing Qa based on the student enrollment numbers from fall 2013, with an assumed unit flow rate of 20 gpd per full-time student and 10 gpd per part-time student. Buildout Qa assumed to be 50 percent higher than the existing Qa. As specified in the NESSMP.. March 2018. n\c\001\21-15-61\WP\WWCSMP Report\060616_Ch 3. 3-7. City of Vacaville Wastewater Facilities Master Plan.

(8) Chapter 3 Model Development 5. Under the General Plan, the golf course is designated as 165 acres of Private Recreation land use for both existing and future conditions. It is understood that a plan now exists to redevelop the site as primarily residential multi-use development. However, any such redevelopment will require an amendment to the General Plan, and the flow impacts of such a development are not yet known. Accordingly, for this analysis, it is assumed that the site will generate 12,000 gpd of flow. 6. For the town of Elmira, the existing Qa is set equal to 24,000 gpd, based on pump run time-based lift station flow data from December 2016. The buildout Qa is based on assumptions of 85 connected residential units, 3.7 acres of service commercial flows, and 284 elementary school students, per previous wastewater collection system planning assumptions. Future flow factors are applied to these land use quantities to account for uncertainties in the analysis. 7. For Solano Community College, flows are estimated based on the student enrollment numbers from fall 2013, with an assumed unit flow rate of 20 gpd per full-time student and 10 gpd per part-time student. Buildout flows are assumed to be 50 percent higher than existing. 8. Buildout Qa from special case flow areas defined as buildout-only in Table 3-3 are as specified in the NESSMP. 3.3.2 Dry Weather Flow Variation. Once the Qa values are established, it is necessary to account for how those flows vary over any given diurnal period. That variation is dependent on whether Qp or Qd is being analyzed. In the case of Qp, a diurnal pattern is applied to the Qa inputs to the model, and the resultant time-varying inputs are aggregated throughout the system as part of a dynamic (time-varying) simulation. The diurnal dry weather flow patterns that are applied are generally specific to the geographic location within the system, and are derived from past flow metering data. In general, the patterns were established as part of the Vacaville General Plan EIR modeling analysis, and have been adjusted, as needed, for the current analysis. In the case of Qd, the following exponential equation is applied to the cumulative Qa values throughout the system to produce a value for peak dry weather flow (Qpwdf), where all the flow values are expressed in units of million gallons per day (mgd): Qpdwf = 2.1·Qa0.943 This equation was derived as part of previous master planning analyses, and was intended to conservatively capture the worst-case Qpwdf throughout the system. Because this equation is applied to the cumulative flows within the system (as opposed to the individual flow inputs), and because the equation is exponential in form, Qpdwf values will not be arithmetically additive. For example, if two trunk lines come together, and each trunk line has a Qa of 1.2 mgd, the resultant downstream Qa will be 2.4 mgd. However, whereas each trunk line will have a calculated Qpdwf of 2.49 mgd, the resultant downstream Qpwdf would be 4.79 mgd, which is less than the sum of the upstream Qpwdf values.. March 2018. n\c\001\21-15-61\WP\WWCSMP Report\060616_Ch 3. 3-8. City of Vacaville Wastewater Facilities Master Plan.

(9) Chapter 3 Model Development 3.3.3 I&I. I&I is handled two ways in the modeling analysis. As with diurnal flow variation, the approach is dependent on whether Qp or Qd is being considered. The method used for Qp modeling is referred to as the RTK method. The method used for Qd analysis is to use predetermined peak per acre I&I rates that apply to overall gross acreage of a given tributary area. 3.3.3.1 RTK Method. For each tributary area (defined by flow metering locations), the RTK method is used to generate wet weather hydrographs that represent the I&I portion of sewer flows during and immediately after significant rainfall events. More specifically, the RTK method represents rainfall-dependent I&I, as compared to long-term groundwater infiltration. The RTK method generates a series of three triangular hydrographs that represent short-term, medium-term, and long-term rainfall response. The RTK parameters include: •. R: The portion of total rainfall within a tributary area that enters the collection system in the form of I&I. •. T: The time from the onset of rainfall to the peak of the I&I response. •. K: The ratio of the time-to-recession to the time-to-peak of the hydrograph, where the time-to-recession is defined as the time from the peak to the point in time where there is no longer any appreciable I&I response. One other parameter of note used in the RTK analysis is the effective area onto which rain is assumed to fall, and from which I&I is generated (referred to in this analysis as AI&I). This parameter varies by location and will also increase over time for areas that have not yet fully developed. For any given tributary area, the parameters are generally derived through a calibration process using collection system flow data from a major storm event. Specifically, the three RTK parameters are derived for each flow-metered area for which applicable peak flow data exist, and AI&I values are derived for each sewershed based on existing collection system, drainage, and land use characteristics. The RTK calibration process is discussed below (see Model Calibration). Once the requisite parameters have been calibrated, the RTK method is then applied to the collection system model using a defined storm event, sometimes referred to as the design storm. For this analysis, the 10-year, 48-hour storm event, as defined in the Solano County Water Agency Hydrology Manual, is used as the design storm. The magnitude of that storm varies depending on the exact location or tributary area being considered. For the Nut Tree Airport, where a National Atmospheric and Oceanic Administration (NOAA) gauge is maintained, the 10-year design storm is defined as producing a total of approximately 5.8 inches of rain in 48 hours.. March 2018. n\c\001\21-15-61\WP\WWCSMP Report\060616_Ch 3. 3-9. City of Vacaville Wastewater Facilities Master Plan.

(10) Chapter 3 Model Development 3.3.3.2 Qd I&I. In the calculation of Qd, fixed rates of I&I are used for all modeled sewersheds. The following I&I rates for the calculation of Qd, as taken from previous master planning analyses, are also used in this analysis. These I&I rates are expressed in units of gallons per acre per day (gpad), and assumed to apply to the gross acreage for any given sewershed, which will generally be greater than the AI&I values described above for the calculation of Qp conditions: •. Standard existing development areas: 1,000 gpad. •. Existing flood-prone areas: 2,500 gpad. •. Greater downtown area: 1,500 gpad. •. Future development areas: 1,000 gpad. The flood-prone areas were defined based on observations made during major storms that occurred in December 2002 and in December 2005. The relevant flood-prone areas and greater downtown areas are depicted on Figure 3-7. 3.3.4 Qp and Qd Calculation. Qp is computed dynamically in the model as the combination of diurnally-varying dry weather flow and I&I simulated using the RTK method. In general, the simulation is performed such that the peak of the storm is timed to coincide with the peak of the diurnal dry weather flow pattern, thus producing a conservatively high peak flow result. The calculation of Qd at any point in the system is simply the sum of the Qpdwf (calculated from the cumulative Qa value, as described above) and the cumulative Qd I&I. As noted above, the Qd analysis is more relevant to buildout conditions than to existing conditions because buildout flows are generally the basis for the design of any new facilities. 3.4 MODEL CALIBRATION. The two major elements of model calibration include dry weather flow calibration, and calibration of the RTK parameters used to calculate I&I in the Qp model simulations. 3.4.1 Dry Weather Flow Calibration. As noted above, the application of the existing development flow factors in Table 3-2 will not necessarily produce results that match with existing flow data. Some adjustment to those flows is therefore necessary when attempting to reconcile modeled dry weather flows with metered flows. Moreover, as noted above, those adjustments will tend to be based on the geographic areas tributary to the flow metering locations rather than on land use type. In Table 3-4, the predicted Qa values for both unadjusted and adjusted conditions are compared to the measured values for the flow metering areas used in the current analysis. For calibration purposes, average flow values from fall 2013 are used. Thereafter, City-wide wastewater flows declined significantly, due at least in part to the ongoing drought. From a modeling standpoint, it. March 2018. n\c\001\21-15-61\WP\WWCSMP Report\060616_Ch 3. 3-10. City of Vacaville Wastewater Facilities Master Plan.

(11) Chapter 3 Model Development is thus assumed that the flow reductions associated with the drought are not permanent, and therefore some offsetting increases are likely to occur in the future. Table 3-4. Modeled versus Measured Qa Values Flow Metered Area. Measured Flow, mgd (a). Unadjusted Model Qa, mgd. Adjustment Factor, percent. 7.56. 66. WWTP. 7.51. Allison Parkway LS. 0.080. 0.186. 0.080. 68. Birch Street. 0.135. 0.231. 0.134. 72. Brown Street LS. 0.107. 0.231. 0.107. 46. CSP-S Trunk. 1.16. 1.16. 1.15. 99. Elmira Road. 1.10. 1.96. 1.13. 56. Fry Road. 1.04. 1.29. 1.04. 81. Leisure Town Road LS. 1.19. 1.67. 1.20. 72. Nut Tree Road. 1.28. 1.81. 1.29. 71. Orange Drive. 1.01. 2.12. 1.02. 48. 0.73. 1.46. 0.73. 50. Downstream (a). (b). Areas (b). 11.47. Adjusted Model Qa, mgd. All measured flows collected during fall 2013 except for Birch Street, which is based on winter water use data from 2006-2010 (see “Updated Analysis of Birch Street Area Sewer Improvement Alternatives”, August 2016). Refers to areas downstream of the major regional flow meters (CSP-S trunk, Elmira Road, Fry Road, Leisure Town Road LS, Nut Tree Road, Orange Drive) and upstream of the Easterly WWTP. Flows are calculated as the difference between the Easterly WWTP value and the sum of the six regional meters.. It should be noted that the indicated adjustments apply to the Qp analysis but not to the Qd calculation. The intended use of the Qd calculation is to allow for the design of future facilities without having to do a full modeling analysis. Geographically-based adjustment factors are one of the complexities associated with the Qp analysis, and they are a moving target due to the fact that wastewater generation rates tend to change over time. The Qd analysis dispenses with any such adjustments in favor of a relatively straightforward calculation procedure that allows for the design of future collection system facilities to take place without requiring a prediction of future variations in flow generation rates. It should be noted that the flow factors shown in Table 3-2 above were most recently updated as part of the 2007 Master Plan, and are based on collection system flow monitoring data from October 2002. Over the past 14 years, municipal water use patterns, and resultant sanitary sewer flows, have been declining on a per capita basis. The adjustment factors shown in Table 3-4 provide a means of adhering to the current City standards while still providing close agreement with recent flow monitoring data. However, the above adjustments are not applied to future development, and they are also not used in the Qd analysis. The result is that Qp and Qd flows representing future conditions tend to be highly conservative, at least for the sanitary (non-I&I) portion of the flow projection. At some point, the City should consider updating the flow factors to more closely represent current and anticipated water use and sewer flow generation patterns.. March 2018. n\c\001\21-15-61\WP\WWCSMP Report\060616_Ch 3. 3-11. City of Vacaville Wastewater Facilities Master Plan.

(12) Chapter 3 Model Development 3.4.2 RTK Calibration. The RTK calibration was performed as part of the modeling analysis performed under the Vacaville General Plan EIR. The parameters so derived are used in the current analysis, including the AI&I parameters discussed above, which have not changed significantly since the prior analysis was performed. The model calibration under the Vacaville General Plan EIR analysis made use of a major storm that occurred on January 3–5. 2008. That storm produced approximately 4.3 inches of rain in a 48-hour period (as compared to approximately 5.8 inches of rain associated with the 10-year 48-hour event), and generated a significant amount of I&I, as measured throughout the system and at the Easterly WWTP. A total of 23 flow meters were deployed throughout the system during that event, which provided the data used for calibration. It should be noted that a considerably larger storm occurred on December 31, 2005. However, it was determined that that event was not suitable for model calibration due to the major flooding that occurred in certain areas, which will tend to distort the distribution RTK values in a manner that is not expected to be representative of a typical 10-year storm event. 3.5 MODELED TIME FRAME SCENARIOS. The following three time-frame scenarios are considered in this analysis: •. Existing Conditions. •. Buildout Conditions. •. Five-Year Development Conditions. As discussed in Chapter 2, neither the existing plus approved land use projection nor the 2035 horizon year land use projection are considered relevant to this analysis because all sewer facilities must ultimately be sized to accommodate buildout flows, not intermediate flows. By contrast, the five-year projection is used to provide a basis for the scheduling of collection systems facilities that may need to be constructed or upsized in the near future. 3.5.1 Existing Conditions. For the existing conditions time frame, the existing conditions land use data from the City land use database (summarized in Table 2-1 in Chapter 2) are used. However, the categories in the database do not exactly match the collection system factors specified in Table 3-2 above. To achieve consistency between the two, the following adjustments are made to the entries in the City land use database: 1. All entries identified as “Building Footprint” in the Notes column are disregarded. 2. All entries listed as “(See Buildout)” in the existing conditions land use columns are disregarded, as these entries represent future parcels that do not currently exist. 3. All entries listed as “College” in the land use columns are handled as special case flows.. March 2018. n\c\001\21-15-61\WP\WWCSMP Report\060616_Ch 3. 3-12. City of Vacaville Wastewater Facilities Master Plan.

(13) Chapter 3 Model Development 4. All entries listed in the land use columns as “Agriculture Buffer,” “Hillside Agriculture,” “Landscape Buffer,” “Miscellaneous,” “Residential Rural,” and “Water” are assumed to be zero flow-producing uses. 5. All entries in the land use columns that are residential in nature, except Residential Rural, are treated as Residential. These uses include the following: •. Manufactured Homes. •. Residential Estates. •. Residential High Density. •. Residential Low Density. •. Residential Low Medium Density. •. Residential Medium Density. •. Retired Multiple Family Residential. •. Retired Single Family Residential. 6. If a parcel is indicated as “Vacant” in the Status column, that parcel is assumed to produce zero flow regardless of the indicated land use. 7. Only existing flow-producing land use areas within the City limits plus the town of Elmira are included in the model. Once the above land use data adjustments are applied, the existing conditions flow factors from Table 3-2 above are applied to the given entries, thereby producing an unadjusted parcel-specific Qa value. For all land uses that are non-residential, non-school, and non-special case, the flow factor is multiplied by the land use polygon area (in acres) to produce the Qa value. For any parcels associated with special case flow sources, the specified land use is disregarded and the Qa specified in Table 3-3 above is used. If there are multiple parcels associated with a single special case flow source (e.g., Genentech), the flows are assigned to one of the constituent parcels and the remaining parcels are assumed to be zero flow. Once all of the parcel-specific Qa values are established, the resultant Qa values are aggregated together into their respective sewersheds. At that point, the appropriate dry weather diurnal flow curves are applied, along with the adjustments indicated in Table 3-4 above. The adjusted diurnally-varying flows from each sewershed are then loaded into the model at their respective nodes. The 10-year 48-hour design storm is then applied to the model, with the result that Qp conditions are simulated throughout the collection system. 3.5.2 Buildout Conditions. For the buildout conditions time frame, the buildout land use data from the City land use database (summarized in Table 2-1 in Chapter 2) are used. As with the existing conditions data, the previously noted adjustments are made to the database entries to get them to correspond to the collection system flow factors specified in Table 3-2 above. The only change from the above adjustment is that areas designated as Residential Rural are no longer treated as zero flow-producing parcels. It should be noted, however, that such parcels will only contribute flow to the model if they fall within an existing or buildout sewershed. March 2018. n\c\001\21-15-61\WP\WWCSMP Report\060616_Ch 3. 3-13. City of Vacaville Wastewater Facilities Master Plan.

(14) Chapter 3 Model Development The buildout conditions scenario uses the existing conditions scenario as a starting point, where existing and future flows are tracked separately. The adjustment factors shown in Table 3-4 above for existing parcels are not applied to future development, thus ensuring conservative Qa estimates for all future development. The following procedures are used: 1. For each parcel, an assessment is made to establish whether any land use changes will occur between existing and buildout. If no changes occur, the adjusted Qa for that parcel from the existing conditions analysis is retained. 2. If a parcel is listed as vacant for existing conditions, the buildout Qa is calculated by multiplying the buildout land use quantity by the appropriate buildout conditions flow factor from Table 3-2 above, with no adjustment applied. 3. If a parcel is categorized as Residential for both existing and buildout conditions, but the number of units increases, the adjusted Qa from the existing conditions analysis is retained, and a future residential flow component is then added to the Qa value. Specifically, for all approved residential parcels (as determined from in the “Ex_Appr_Un” data column), the Existing+Approved Development flow factor specified in Table 3-2 above is applied. For all future residential parcels that are planned but not yet approved, the Future Development flow factor specified in Table 3-2 above is applied. In either case, no adjustment is applied to the future residential development portion of the Qa for the parcel. 4. If the designated land use changes from existing to buildout conditions, the existing conditions Qa value is disregarded, and the buildout Qa is calculated by multiplying the buildout land use quantity by the appropriate buildout conditions flow factor from Table 3-2 above, with no adjustment applied. 5. All entries listed as “(See Buildout)” in the buildout conditions land use columns are disregarded, as these entries represent existing parcels that will be superseded by future development parcels. 6. Only buildout flow-producing land use areas within the urban growth boundary plus the town of Elmira are included in the model. As with the existing conditions model, once all the parcel-specific Qa values are established, the resultant Qa values are aggregated together into their respective sewersheds, at which point the appropriate dry weather diurnal flow curves are applied. The diurnally-varying flows from each sewershed are then loaded into the model at their respective nodes. As with the existing conditions model, the 10-year, 48-hour design storm is applied to the model using the calibrated RTK factors. For parcels that are not fully developed under existing conditions, the future AI&I value for the parcel is estimated such that the given parcel will generate a peak I&I value of roughly 2,000 gpad, which corresponds to the approximate City-wide peak I&I during past major storm events. For buildout conditions, a Qd analysis is also performed. In that case, the existing and future Qa portions are combined; however, no adjustment is applied to the existing conditions portion of the Qa. The exponential Qpdwf equation and Qd I&I values are then applied, as described in Section 3.3.. March 2018. n\c\001\21-15-61\WP\WWCSMP Report\060616_Ch 3. 3-14. City of Vacaville Wastewater Facilities Master Plan.

(15) Chapter 3 Model Development 3.5.3 Five-Year Development Conditions. The City land use database contains two columns that specify projected development for the fiveyear land use development condition. These two data columns provide estimates of the number of residential units and the building square footage associated with non-residential development, respectively. Accordingly, five-year Qa flows are estimated as follows: 1. For each parcel, if no changes in development are indicated from existing conditions to the five-year development condition, the Qa for that parcel from the existing conditions analysis is retained. 2. If a parcel is categorized as Residential for existing conditions, and if there is an increase in the number of units from existing to five-year, the adjusted Qa from the existing conditions analysis is retained, and a future residential flow component is then added in a manner similar to the buildout conditions calculation just described where approved and not-yet-approved residential development are handled separately. 3. If a parcel is listed as vacant for existing conditions, and if the five-year data indicate that some development will occur in that time frame, the ratio of the five year building square footage and the buildout building square footage is applied to the parcel area, and the result is multiplied by the appropriate land use-based flow factor to obtain the five-year Qa. 4. If the designated land use changes from existing to buildout conditions, and the fiveyear data indicate that some development will occur, the existing Qa value is disregarded, and the five-year Qa is interpolated from the buildout Qa based on the ratio of five-year development to buildout development. 5. It is assumed that special case flows remain unchanged from existing conditions. Once all the parcel-specific Qa values are established, the resultant Qa values are aggregated together into their respective sewersheds, at which point the appropriate dry weather diurnal flow curves are applied. The diurnally-varying flows from each sewershed are then loaded into the model at their respective nodes and the 10-year, 48-hour design storm is applied to the model using the calibrated RTK factors. For any parcels in which future development is indicated in the five-year time frame, the buildout AI&I value is used for I&I calculation.. March 2018. n\c\001\21-15-61\WP\WWCSMP Report\060616_Ch 3. 3-15. City of Vacaville Wastewater Facilities Master Plan.

(16) 0. 2,000. 4,000. Scale in Feet. LEGEND. 505. City Limit Boundary. Allison Parkway LS. Urban Growth Boundary. Sphere of Influence Boundary. Easterly Wastewater Treatment Plant. Leisure Town Rd. Vaca Valley Parkway LS. Horse Creek LS. Modeled Lift Station. Existing Modeled Gravity Main Existing Modeled Force Main Unmodeled Sewer Facilities. Leisure Town Road LS. Parallel gravity sewers 80 Notes: 1. Modeled existing collection system pipelines based on AutoCAD Sewer Network file and plan sets received from the City.. D mo Ala. 2. Unmodeled pipelines shown based on 2015 AutoCAD Sewer Network file received from the City in December 2015.. r.. Elmira Rd. B Street LS. Nut Tree Rd.. Grandview LS. Alamo Dr.. Peabody Rd.. Last Saved: 3/22/2018 3:39:10 PM \\DA S-FS1\Davis\Clients\001 Vacaville\21-15-61 WW CS MP Update\GIS\Figures\Figure3-1_Ex_Infrastructure.mxd : ekluge. Brown Street LS. Fry Rd.. Figure 3-1. Modeled Existing Conditions Infrastructure City of Vacaville Wastewater Facilities Master Plan.

(17) North Village LS 0. LS-I. 505. Quinn Road LS. Allison Parkway LS Vaca Valley Parkway LS. Orange Drive LS. The alignment options shown are conceptual, and have been created for planning purposes only. The actual future alignment has yet to be determined and will be subject to environmental analysis.. 2,000. 4,000. Scale in Feet. LEGEND. City Limit. Urban Growth Boundary. Sphere of Influence Boundary. Easterly Wastewater Treatment. Existing Modeled Lift Station Future/Upsized Modeled Lift Existing Modeled Gravity Main. Horse Creek LS. Existing Modeled Force Main. 80. Future/Upsized Modeled Gravity Future Modeled Force Main Future Modeled Force Main (Alternative Alignments). LS-II. Unmodeled Sewer Facilities. Parallel gravity sewers. D mo Ala. Junction structure required; see Chapter 5. r. Nut Tree Rd.. Elmira Rd.. Grandview LS. B Street LS. Alamo Dr.. Peña Adobe LS. Peabody Rd.. Last Saved: 8/9/2017 2:33:35 P M \\DAS-FS 1\Davis\Clients\001 Vacaville\21-15-61 WWCS MP Update\GIS\Figures\Figure3-2_BO_Infrastructure.mxd : ekluge. Brown Street LS. Leisure Town Rd. Leisure Town Road LS. Notes: 1. Modeled existing collection system pipelines based on AutoCAD Sewer Network file and plan sets received from the City. 2. Unmodeled pipelines taken from AutoCAD mapping data received from the City in December 2015.. Fry Rd.. Figure 3-2. Modeled Buildout Conditions Infrastructure City of Vacaville Wastewater Facilities Master Plan.

(18) 103164. 103163. 103161. 101376. 103156 103159. 103158. 103155. 103150. 103152. 101970b. 103151. 104663a. 104663b. 100452. 104727. 101380b. 101970a. 101960. 104770. 104896b. 0. 101380a. 101966 104779b 103207 101381 104840 101965 101959 104725 104779a 103211 105161 101962 104571 104838 104802 103209 104842 103281d 104664 101953 104865b 103208a 104560c 505 101956 101949 104528 104919 104780b 104560b 103208b 103281c 104560d 101952 105158 104780a 103216 104865a 104560a 103281b 101951 103281a 103219 103218 105171a 104869 104896a 105170 101374 103282 103858 103854 103225 101941a 101371 101941b 105168 104927 103845 103215 101943 105166 105433 104927 101365 101938 103919 101933 100439 101361 103947 103200 104890 103880 100433 101936 103221 101932 100445 105057 103888a 105061 101931 101935 103888b 101364 105444 103188 104047 105047 105434 105445 104012 103187 100063 105443 104011 101928 104663c. 104568. 104094. 102511. 103083. Last Saved: 8/9/2017 2:37:59 P M \\DAS-FS 1\Davis\Clients\001 Vacaville\21-15-61 WWCS MP Update\GIS\Figures\Figure3-3_ExistingSheds.mxd : ekluge. 102495 102483. 103039. 103040b. 103049. 103040c 103047. 103715. 102558. 103167. 105277. 102922. 103784 102540. 103791a. 104311. 100390. 102884 103762. 102304. 103791b. 104317. 105123. 105120b 105118. 102219. 101576. 102153. 105080. 100878 100569. 101504. 100605b 100605a. 101451. 102070. 100839 100836 100835. 101392. ST00. ST01A. 101386. 105239b. 102077. 103827 101382. 101384. 100585. Fry Rd.. 101522. 100877. 103836. 102039. ELMIRA 105207. 100658. 101596. 101537. 102041. 3. Where Urban Growth Boundary and Sphere of Influence Boundary coincide, the Urban Growth Boundary is shown on top. Where the City Limit Boundary coincides with either of the other two boundaries, the City Limit Boundary is shown on top.. Elmira Rd.. 105105. 101538. 102168. 2. Urban Growth Boundary and City Limit Boundary received from City staff in March 2016. Sphere of Influence Boundary received in July 2017.. Elm15. 101580a. 102166. 105075. Elm09. Elm06. 105110 105104 101580b. 101599. 104412. Notes: 1. Existing shed boundaries are based on existing system infrastructure received from City staff in December 2015.. 100733. 105103. 102216. 104321. 104438. 100061 100056. 100212. 105204. 101718. 105120a. 105128. 104274. 105084. 100206. 105253. 105132. 102881. 101302. 100069. 101859 101850. 105083. 102311. Sphere of Influence Boundary (See Note 3). 105046b. 101741. 104184 105259. Urban Growth Boundary (See Note 3). 105046a. 101182b. 104207. 103721. 103723. 101179 101202c 101192. 101795. 103588. 100808. 101319 101321 101304 101294 101297 101296. 101202a. 101182c. 101801. 104133. 103616 103570. 101904. 102383. 105190. 103605 102950 103611. 103720. 80. 101342 101278. 101182a. 104159. 103489. 105195. 102627 102569 102581. Brown_10. BROWN_1 103040a. 102975. 104111. 103056. 103075. 102489. 102633. 104621. City Limit Boundary (See Note 3). 105043. 101202b. 104604. 102731. LEGEND. 105243. 105449. 100436. 104612a. 104089. 104083. 103134. 104612b. Scale in Feet. Leisure Town Rd. 103183. 103130b. 4,000. 105040. 101923b. 104601. 102784. 102751. 101354. 101923a. 104020. 102791. 105441. 105448 101927. 104039. 103130a 102793. 105288. 104013. 104049. 2,000. 100833 101385. 100838 ST06. 105236. 104509. ST05. ST04. 105239a. 100542. ST07 ST08. V01. Figure 3-3. Modeled Existing Conditions Sewersheds City of Vacaville Wastewater Facilities Master Plan.

(19) 103164. JR 48Aa. 103163. 103161. 101376. 103159. 103156. 103150. 101380b. 101970a 100452. 104727. 104663c. 101960. 103207. JR 49. 104012. JR 51b. 104896b. 101380a. 102793. 103130b 104083. 103134. 104094 103083. Last Saved: 8/9/2017 2:38:42 P M \\DAS-FS 1\Davis\Clients\001 Vacaville\21-15-61 WWCS MP Update\GIS\Figures\Figure3-4_BuildoutSheds.mxd : ekluge. 102483. 103040a 103039. 103040b. 103049. 103040c 103047. 103720 102922. 102950. 103721. 102540. 103791a. 100390. 102884 103762. LLV_MH2a. 104184 105259. 103791b. LLV_MH3. 102304. 105120b. 105123. 105110. 105118. 100733. 102219. 101576. 101538. JR 36b JR 36a. 100878. 101504. 103836. 100569. 100605b 100605a. 100839. 101451. 100838. ST00. 102077 101386. ST01A ST02 105239b 105239a. 101382. 101384. 100833 101385. 104509. ST08. ST04. 100835. 103827. RR01a. 105080. RR01b. Fry Rd. JR 37Bb. 100542. ST07 ST05. ST06. 100836. 102070 101392. 100585. 101522. 100877. 101537. 102039. ELMIRA. JR 36c 105207. 100658. 105104 101580b. 2. Where Urban Growth Boundary and Sphere of Influence Boundary coincide, the Urban Growth Boundary is shown on top. Where the City Limit Boundary coincides with either of the other two boundaries, the City Limit Boundary is shown on top.. JR 98Ab. 105075. Elm15. 101596. 101599. 102041. Notes: 1. Urban Growth Boundary and City Limit Boundary received from City staff in March 2016. Sphere of Influence Boundary received in July 2017.. JR 32Fa. 105105. 102153. LLV_MH8. Sphere of Influence Boundary (See Note 2). JR 32Fb. Elm09. Elm06. 101580a. 102166. LLV_MH4. LLV_MH7b. 100056. 100212. 105103. 105120a. 102168. LLV_MH7a. Urban Growth Boundary (See Note 2). JR 14. JR 32A. JR 98Aa. 101718 105253. 104412. 104438. 100061. 105204. 102216. 104321. City Limit Boundary (See Note 2). 100206. 105128. 104274. 104317. LLV_MH2b. 100069. 101859 101850. 105083. 105132. 102881. 101182b. 101741. 104311. LEGEND. JR 26. 105043. 105449. 101795. 102311. 103723. JR 12. Scale in Feet JR 4A. 100436. 104207. 103588. JR 14A. 4,000. 105243. 105040. 101801. 104133. 103605 103611. 103784. 80. 102383. 105190. 105277 103616 103570. 102627 102569. 102558. 103167. 104159. 103489. 105195. 103715. 102581. Brown_10. BROWN_1. 102489. 102975. 104111. 103056. 103075. 102633. 104612b. 104089. 102731. JR 13. 2,000. 101342 100808 105046b 101278 105046a 101319 101321 101202b 104612a 101294 101304 JR 27 101297 101182a 101296 104604 101179 101202a 101302 104621 101202c JR 29b 101904 JR 29a 101182c 101192 105084. 103183. 102511. 102495. 104601. 102784. 102751. 101354. 101927. 101923b. 0. JR 51a. 100063. 101923a. 104020. 102791. 105441. 105448. 104039. 103130a. 105443. 101928. 105288. 104013. 104049. 105434. 105445. 103187. 104011. JR 1. JR 3. JR 5. 104770. 101381 104840 104779a 101965 104725 101959 103211 101962 105161 104571 104664 104838 104779b 104802 104842 103281d 103209 101953 104560b 103208a 104865b 505 104560c 101956 104528 101949 104780b 103208b 103281c 104560d 104865a 104919 101952 QR01 105158 104780a 103216 104560a 103281b 101951 104869 103281a 103219 103218 105171a 101374 103282 103858 103854 103225 101941a 104896a 101371 101941b 105173 104927 103845 105433 101943 105168 103215 101938 105166 101365 104927 103919 101933 100439 103947 103200 104890 103880 100433 101361 JR 14B 101936 103221 OD02 101932 100445 105057 103888a 105061 101931 101935 105047 103888b 101364 105444 103188 104047 104568. JR 47. JR 48Ab. NV_MH3. 103152 103151. 101970b. 104663a. NV_MH1a. 103158. 103155. 104663b. NV_MH1b. JR 37Ba. 100509. V01. ST03b ST03a. 105236. Figure 3-4. Modeled Buildout Conditions Sewersheds City of Vacaville Wastewater Facilities Master Plan.

(20) 0. 2,000. 4,000. Scale in Feet. 505. LEGEND. City Limit Boundary (See Note 2). Urban Growth Boundary (See Note 2). Sphere of Influence Boundary (See Note 2) Modeled Gravity Main Modeled Force Main. Existing Special Case Alza. CMF. CSP-S. Easterly WWTP GCC WWTP Groundwater. Leisure Town Rd. 80. D mo Ala. Genentech. Green Tree Golf Course Kaiser. Mariani. Matheson Tri-Gas Save-Mart. r.. Solano College. Elmira Rd.. Vaca Valley Hospital. Nut Tree Rd.. EWWTP. Peabody Rd.. Last Saved: 8/9/2017 2:41:30 P M \\DAS-FS 1\Davis\Clients\001 Vacaville\21-15-61 WWCS MP Update\GIS\Figures\Figure3-5_Existing S pecial Case Map.mxd : ekluge. Elmira. Alamo Dr.. Fry Rd.. Notes: 1. Urban Growth Boundary and City Limit Boundary received from City staff in March 2016. Sphere of Influence Boundary received in July 2017. 2. Where Urban Growth Boundary and Sphere of Influence Boundary coincide, the Urban Growth Boundary is shown on top. Where the City Limit Boundary coincides with either of the other two boundaries, the City Limit Boundary is shown on top.. Figure 3-5. Existing Special Case Flow Sources. City of Vacaville Wastewater Facilities Master Plan.

(21) 505. 0. 900. 1,800. Scale in Feet. LEGEND. City Limit Boundary (See Note 2). Urban Growth Boundary (See Note 2). Sphere of Influence Boundary (See Note 2) Modeled Gravity Main Modeled Force Main. Future Special Case Areas Area A. Area B Area E. Area E1. Leisure Town Rd. Last Saved: 8/9/2017 2:45:40 P M \\DAS-FS 1\Davis\Clients\001 Vacaville\21-15-61 WWCS MP Update\GIS\Figures\Figure3-6_Future Special Case Areas.mxd : ekluge. Area W. 80. Laurelwood-Alza Transfer Mission Area E. Vacaville BP & Vicinity. VacaValley Business Park. Notes: 1. Urban Growth Boundary and City Limit Boundary received from City staff in March 2016. Sphere of Influence Boundary received in July 2017. 2. Where Urban Growth Boundary and Sphere of Influence Boundary coincide, the Urban Growth Boundary is shown on top. Where the City Limit Boundary coincides with either of the other two boundaries, the City Limit Boundary is shown on top.. Figure 3-6. Future Special Case Areas City of Vacaville Wastewater Facilities Master Plan.

(22) 0. 2,000. 4,000. Scale in Feet. 505. LEGEND. City Limit Boundary (See Note 2). Urban Growth Boundary (See Note 2). Sphere of Influence Boundary (See Note 2). Sewersheds. High I&I Area. Greater Downtown Area. Standard Existing Development Area Future Development Areas Unsewered Areas. Last Saved: 8/9/2017 2:47:35 P M \\DAS-FS 1\Davis\Clients\001 Vacaville\21-15-61 WWCS MP Update\GIS\Figures\Figure3-7_IIAreasQd.mxd : ekluge. 80. Notes: 1. Urban Growth Boundary and City Limit Boundary received from City staff in March 2016. Sphere of Influence Boundary received in July 2017. 2. Where Urban Growth Boundary and Sphere of Influence Boundary coincide, the Urban Growth Boundary is shown on top. Where the City Limit Boundary coincides with either of the other two boundaries, the City Limit Boundary is shown on top.. Figure 3-7. I&I Areas Used for Qd Analysis. City of Vacaville Wastewater Facilities Master Plan.

(23)

No results found