HomeMy WebLinkAboutTechnical Report 8a - Water Conservation PlaMaria Miller
May 28, 2024
Page 2
The proposed land use changes will reduce the amount of single family dwelling units and
increase the amount of multi-family dwelling units within Village 7; however, the proposed
changes would result in no net change to the residential dwelling unit count of 1,456
presented in the Otay Ranch General Development Plan for Village 7. To implement the
proposed land use changes, amendments to the Chula Vista General Plan, Otay Ranch
General Development Plan, and the Village 7 SPA Plan are necessary.
The October 2004 Water Conservation Plan for Village 7 was prepared as a supporting
document to the project’s Environmental Impact Report dated October 12, 2004. The purpose
of this memorandum is to evaluate the impact of the proposed land use changes for Village 7
on the findings from this previous study.
Village 7 SPA Amendment Summary
A summary of proposed changes to the Village 7 land use plan is provided as follows:
• Rename the western portion of Parcel R-3 into a separate Parcel R-8. Parcel R-8 will
be located adjacent to La Media Road.
• Assign 43 units to Parcel R-3 and change the land use designation in Parcel R-3 from
Single Family to Residential Multi-Family.
• Assign 121 units to Parcel R-4 and change the land use designation in Parcel R-4 from
Single Family to Residential Multi-Family.
• Assign 123 units to Parcel R-8 and change the land use designation (based on Parcel
R-3 land use designation) in Parcel R-8 from Single Family to Residential Multi-
Family.
Maria Miller
May 28, 2024
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Proposed Land Use Plan
The project does not propose changes to the backbone street alignments for Village 7 but does
involve adjustments to the land use and residential unit count of Parcels R-3 and R-4, and
the addition of Parcel R-8. A land use plan and site utilization table for the proposed changes
are included in Attachment 1 for reference.
Water Demand Projection – Approved Plan
Table 1 summarizes the projected average water demands for Village 7 based on the approved
land use plan as presented in the March 2004 Conceptual Water and Recycled Water Study.
Table 2 summarizes the projected average day water demands from the November 2004
Subarea Master Plan (SAMP) for Village 7. The difference in demand is based on lotting
studies completed after the March 2004 Study.
TABLE 1
OTAY RANCH VILLAGE 7
PROJECTED WATER DEMAND (MARCH 2004 STUDY)
Land Use Proposed Units Demand Factor Average Demand,
gallons per day (gpd)
SF Residential 1,053 units 500 gpd/unit 526,500
MF Residential 448 units 300 gpd/unit 134,400
Elementary School 11.1 acres 1,785 gpd/acre 19,814
Middle School 26.3 acres 1,785 gpd/acre 46,946
High School 55.8 acres 1,785 gpd/acre 99,603
Commercial 3.7 acres 1,785 gpd/acre 6,604
Town Square 1.9 acres 2,155 gpd/acre 4,094
Park 7.6 acres 2,155 gpd/acre 16,378
Community Purpose Facility 4.1 acres 893 gpd/acre 3,661
TOTAL 858,000
Maria Miller
May 28, 2024
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TABLE 2
OTAY RANCH VILLAGE 7
PROJECTED WATER DEMAND (NOVEMBER 2004 SAMP)
Land Use Proposed Units Demand Factor Average Demand,
gallons per day (gpd)
SF Residential 1,011 units 500 gpd/unit 505,500
MF Residential 444 units 300 gpd/unit 133,200
Elementary School 11.1 acres 1,785 gpd/acre 19,814
Middle School 26.3 acres 1,785 gpd/acre 46,946
High School 55.8 acres 1,785 gpd/acre 99,603
Commercial 3.7 acres 1,785 gpd/acre 6,604
Town Square 1.9 acres 1,785 gpd/acre 3,391
Community Purpose Facility 2.3 acres 893 gpd/ace 2,054
TOTAL 817,112
Water Demand Projection – Proposed Plan (SPA Amendment)
Table 3 summarizes the projected average water demands for Village 7 based on the proposed
SPA Amendment. This projection uses current water demand factors from the 2015 OWD
Water Master Plan. The decrease in water demand factors compared to the 2004 studies is
due to water conservation efforts in recent years.
Maria Miller
May 28, 2024
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TABLE 3
OTAY RANCH VILLAGE 7
PROJECTED WATER DEMAND (SPA AMENDMENT)
Land Use1 Proposed Units Demand Factor Average Demand,
gallons per day (gpd)
SF Residential 721 units 435 gpd/unit 313,635
MF Residential 735 units 170 gpd/unit 124,950
Elementary School 11.5 acres 1,428 gpd/acre 16,422
High School 53.9 acres 1,428 gpd/acre 76,969
Commercial 3.7 acres 1,607 gpd/acre 5,946
Town Square 1.9 acres 1,607 gpd/acre 3,053
Park2 7.6 acres 0 gpd/acre 2,160
Community Purpose Facility 4.1 acres 714 gpd/acre 2,927
TOTAL 546,062
1. The Middle School and CPF-4 sites that were included in the original SPA for Village 7 are excluded from
Table 3 (SPA Amendment), as they are now part of Village 8 West.
2. Parks are irrigated with recycled water, but a nominal amount of potable use has been estimated.
In comparing the projections from Tables 1 and 2 to Table 3, the proposed SPA Amendment
will reduce previous water demand projections for Village 7 by approximately 36.4 percent
compared to the March 2004 Conceptual Water and Recycled Water Study and by
approximately 33.2 percent compared to the November 2004 Subarea Master Plan.
Water Conservation Savings
A Water Conservation Plan (WCP) was prepared in 2004 with the initial SPA approval within
Village 7 which included only a portion of the village (see Exhibit WC-2 from the 2004 WCP
in Attachment 2). The portion of Village 7 analyzed in the 2004 WCP included 1,204 dwelling
units consisting of 756 single family dwelling units and 448 multi-family dwelling units. The
2004 WCP estimated water conservation savings from the use of recycled water and the
implementation of water conservation measures in single family and multi-family residences.
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May 28, 2024
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Table 4 summarizes the projected recycled water demands from the 2004 WCP. Table 5
summarizes the projected water conservation savings from the 2004 WCP.
TABLE 4
OTAY RANCH VILLAGE 7
PROJECTED RECYCLED WATER DEMANDS (OCTOBER 2004 WCP)
Land Use Area,
acre
%
Irrigated
Irrigated
Area, acre
Average
Demand,
gallons per day1
Irrigated Open Space 47.8 50 23.9 51,433
Park 7.6 100 7.6 16,355
Community Purpose Facility 2.8 20 0.6 1,291
MF Residential 37.9 15 5.7 12,234
Elementary School 11.1 20 2.2 4,777
High School 23.4 20 4.7 10,114
Streets 62.9 10 6.29 13,536
TOTAL 109,740
1. Based on a recycled water demand factor of 2,152 gpd/ac.
TABLE 5
OTAY RANCH VILLAGE 7
ESTIMATED WATER SAVINGS (OCTOBER 2004 WCP)
Description Units
Water Savings,
gallons per
day per unit
Total Water
Savings, gallons
per day
Recycled Water (Table 4) --- --- 109,740
Single Family Residential (McMillin)1 346 46.2 15,985
Single Family Residential (Otay Ranch Co.)1 410 90.0 36,900
Multi-Family Residential 448 16.6 7,437
TOTAL 1,204 170,062
1. In addition to the water conservation measures mandated by the City of Chula Vista, each property owner
implemented one other non-mandatory water conservation measure: McMillin selected Water-Efficient
Landscaping and Otay Ranch Co. selected Evapotranspiration Controllers.
Maria Miller
May 28, 2024
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Recycled Water Demand Projection – Proposed Plan (SPA Amendment). Based on
the proposed SPA Amendment, the recycled water demands and water conservation savings
presented in the 2004 WCP were updated to reflect the land use plan and site utilization
table shown in Attachment 1. Table 6 presents the projected recycled water demands for
Village 7 based on the proposed SPA Amendment.
TABLE 6
OTAY RANCH VILLAGE 7
PROJECTED RECYCLED WATER DEMANDS (SPA AMENDMENT)
Land Use Area,
acre
%
Irrigated
Irrigated
Area, acre
Average
Demand,
gallons per day1
Irrigated Open Space 45.6 50 22.8 43,320
Park 7.6 100 7.6 14,440
Community Purpose Facility (CPF) 4.1 20 0.8 1,520
MF Residential 48.5 15 7.3 13,870
Elementary School 11.5 20 2.3 4,370
High School 53.9 20 10.8 20,520
Streets2 62.9 10 6.3 11,970
TOTAL 110,010
1. Based on the OWD’s current recycled water demand factor of 1,900 gpd/ac.
2. Acreage is from the 2004 WCP. This is a conservative value, as the Middle School and CPF-4 sites that
were included in the original SPA for Village 7 are now part of Village 8 West.
Maria Miller
May 28, 2024
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The water conservation savings for the multi-family units proposed within Parcels R-3, R-4,
and R-8 were determined based on the mandatory and non-mandatory indoor water
conservation measures the developer will implement in each unit. The mandatory indoor
water conservation measures entail installing hot water pipe insulation, pressure reducing
valves, and water efficient dishwashers. The non-mandatory indoor water conservation
measure entails installing dual-flush toilets. Since Parcels R-3, R-4, and R-8 do not propose
any single-family residences, all outdoor irrigation water use is proposed to be met with
recycled water. Thus, there are no outdoor water measures that would result in a direct
reduction in potable water use. Table 7 summarizes the estimated water savings for the
multi-family units proposed within Parcels R-3, R-4, and R-8 based on the mandatory and
non-mandatory water conservations measures that are to be implanted.
TABLE 7
OTAY RANCH VILLAGE 7
PARCELS R-3, R-4, AND R-8 WATER CONSERVATION MEASURES
Water Conservation Measure Location2
Yearly Water
Savings, gallons
per unit
Daily Water
Savings, gallons
per day per unit
Hot Water Pipe Insulation Indoor 2,400 6.58
Pressure Reducing Valves Indoor 1,800 4.93
Water-Efficient Dishwashers Indoor 650 1.78
Dual-Flush Toilet Indoor 4,000 10.96
TOTAL 8,850 24.25
1. One toilet per multi-family unit is assumed. It is estimated that a dual-flush toilet can save 4,000 gallons
per year per toilet.
2. All outdoor irrigation water use for Parcels R-3, R-4, and R-8 is proposed to be met with recycled water;
thus, there are no outdoor water measures that would result in a direct reduction in potable water use.
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May 28, 2024
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Based on the current proposed SPA Amendment, Table 8 summarizes the total estimated
water conservation savings for Village 7.
TABLE 8
OTAY RANCH VILLAGE 7
ESTIMATED WATER SAVINGS (SPA AMENDMENT)
Description Units
Water Savings,
gallons per
day per unit
Total Water
Savings, gallons
per day
Recycled Water (Table 6) --- --- 110,010
Single Family Residential (McMillin) 346 46.2 15,985
Single Family Residential (Otay Ranch Co.) 375 90.0 33,750
Multi-Family Residential (2004 WCP) 448 16.6 7,437
Multi-Family Residential
(Parcels R-3, R-4, and R-8) 287 24.25 6,960
TOTAL 1,456 174,142
Conclusion
The proposed SPA Amendment for Village 7 will result in an increase in recycled water
demand and total water conservation savings as compared to the 2004 WCP. In comparing
the recycled water demand projections from Table 4 to Table 6, the proposed SPA
Amendment will increase previous recycled water demand projections by 270 gallons per day
(gpd), from 109,740 gpd to 110,010 gpd, or approximately 0.2 percent compared to the 2004
WCP. In comparing the total water conservation savings from Table 5 to Table 8, the
proposed SPA Amendment will increase the previous total water conservation savings by
4,080 gpd, from 170,062 gpd to 174,142 gpd, or approximately 2.4 percent compared to the
2004 WCP. The increase in recycled water demand and total water conservation savings in
Village 7 is mainly due to the increase in the number of residential units analyzed: 1,204
units in the 2004 WCP versus 1,456 units in the proposed SPA Amendment.
FF:ah
ATTACHMENT 1
SITE UTILIZATION PLAN
AND
LAND USE SUMMARY TABLE
INTRODUCTION
SPA PLAN
Village 7 Site Utilization Plan
Exhibit 1.6
INTRODUCTION
SPA PLAN
Village 7 Land Use Districts
Exhibit PC-1
Village Seven Site Utilization Table
RESIDENTIAL USE
Neighborhood Land Use LU District Acres DU du/ac
R-1
Single-Family
Detached SF4 53.1 346 6.5
R-2
Single-Family
Detached SF4, RM1 51 375 7.4
Sub-total single-family: 721
R-3 Multi-Family RM1 2.4 43 17.9
R-4 Multi-Family RM2 3.1 121 39
R-5 Multi-Family RM1 14.5 132 9.1
R-6 Multi-Family RM2 12.3 193 15.7
R-7 Multi-Family RM2 7.9 123 15.6
R-8 Multi-Family RM1 8.3 123 14.8
Sub-total multi-family: 735
Total Residential 152.6 ac. 1,456 9.5
NON-RESIDENTIAL USE
Neighborhood Land Use LU District Acres
P-1 Public Park P 7.6
CPF-1 Private Park CPF 1.1
CPF-2a Private Park CPF 0.9
CPF-2b CPF CPF 1.0 *Area included in R-3
S-1 High School S 53.9
S-3 Elem. School S 11.5
OS Open Space OS 42.6
Total Non-Residential 118.6 ac.
FUTURE DEVELOPMENT AREA - CONCEPTUAL USES
(REQUIRES A SPA AMENDMENT TO OBTAIN DEVELOPMENT APPROVAL)
Neighborhood Land Use LU District Acres
R-9 Residential Undesignated 42
MU Mixed-Use Undesignated 3.7
OS Open Space Undesignated 3
TS-1 Town Square Undesignated 1.9
CPF-3 CPF Undesignated 1.1
Total Future Development 51.7 ac.
VILLAGE TOTAL 321.9 ac.
ATTACHMENT 2
EXHIBIT WC-2 FROM
2004 WATER CONSERVATION PLAN