CC 2021-06-22_08l Monthly Water Supply and Demand Update_MayMEMORANDUM
TO: CITY COUNCIL
FROM: BILL ROBESON, ASSISTANT CITY MANAGER/PUBLIC WORKS
DIRECTOR
BY: SHANE TAYLOR, UTILITIES MANAGER
SUBJECT: MONTHLY WATER SUPPLY AND DEMAND UPDATE
D ATE: JUNE 22, 2021
SUMMARY OF ACTION:
The update reports the water supply and demand for May 2021. Current Lopez Lake
level and projected levels are provided in the attachments.
IMPACT ON FINANCIAL AND PERSONNEL RESOURCES:
Approximately two (2) hours of staff time is required to prepare the report.
RECOMMENDATION:
It is recommended the City Council receive and file the Monthly Water Supply and
Demand Report.
B ACKGROUND:
On April 25, 2017, the City Council, by Resolution, rescinded the Stage 1 Water Shortage
Emergency along with related emergency water conservation measures and restrictions.
During that public meeting, Council requested that staff continue preparing the monthly
water supply and demand updates. Council urged citizens to continue to practice
everyday water saving measures, and reiterated that the previously adopted water
conservation measures were to remain in effect. In response to Council discussion on
April 27, 2021, staff has begun to provide notice to customers in non-compliance of the
mandatory water conservation measures by hanging door tags. In addition, four social
media posts have been posted to the City’s social media channels reminding customers
of the measures, and information is highlighted on the City’s website. Staff has organized
a drought response team to begin the process of enhancing public awareness of the
drought and preparing for upcoming water shortage measures.
In May 2021, the City’s water use was 223.4 acre-feet with a per capita use of 133 gallons
per day/per person. There was no rainfall in May 2021. The water use for the current
“rolling” water year from June 2020 to May 2021 was 2,400.6 acre-feet which equates to
a per capita use of 121 gallons per day per person. There was a total of 9.41 inches of
rain fall for this period.
Item 8.l. - Page 1
CITY COUNCIL
MONTHLY WATER SUPPLY AND DEMAND UPDATE
JUNE 22, 2021
PAGE 2
ANALYSIS OF ISSUES:
The United States Drought Monitor, as of June 11, 2021, shows San Luis Obispo County
in an extreme drought. Rainfall to date for the period July 1, 2020, through June 11, 2021,
is 9.11 inches at the Corporation Yard rain gauge. Lopez Lake, as of June 11, 2021, is
at 36% capacity (17,794 acre-feet of storage).
The new water year began on April 1, 2021, and the City’s current total available supply
from Lopez is 2,290 acre-feet. In addition, the City has 1,323 acre-feet of ground water
entitlement from the Santa Maria Basin, and 160 acre-feet from the Pismo Formation.
The second quarter monitoring for the sentry wells was completed in April. The deep well
index was 9.06 feet above sea level, which is 1.56 feet higher than the deep well index
threshold value of 7.5 feet. This is 2.43 feet lower than the index value one year ago
(11.48 feet). The projected water use for the city of Arroyo Grande for water year 2021/22
is 2,450 acre-feet based on current rainfall.
The State Water Resources Control Board, on March 22, 2021, issued a letter stating that
95% of California is experiencing Moderate to Exceptional Drought. Hydrological
conditions since 2020 have been very similar to the drought years of 2014 and 2015. The
County Flood Control & Water Conservation District has not declared a water shortage
emergency or enacted the Low Reservoir Response Plan. County staff is awaiting an
action from the State, such as an Emergency Declaration which includes San Luis Obispo
County. Per the City of Arroyo Grande Municipal Code Section 13.07.030, a Stage 1
water shortage emergency may be implemented with the triggering condition of Lopez
Reservoir reaching or falling below 15,000 acre-feet. The current Lopez Reservoir
Storage Projection shows the 15,000 acre-feet storage level is anticipated to occur on
October 1, 2021.
ADVANTAGES:
This report provides the City Council and the public with the current and projected
conditions of our water supply and demand.
DISADVANTAGES:
No disadvantages noted at this time.
ALTERNATIVES:
Not applicable at this time.
ENVIRONMENTAL REVIEW:
No environmental review is required for this item.
PUBLIC NOTIFICATION AND COMMENTS:
The Agenda was posted at City Hall and on the City’s website in accordance with
Government Code Section 54954.2.
Item 8.l. - Page 2
CITY COUNCIL
MONTHLY WATER SUPPLY AND DEMAND UPDATE
JUNE 22, 2021
PAGE 3
Attachments:
1. Lopez Monthly Operations Report for May 2021
1.a. Lopez Monthly Operations Report for March 2020
2. Lopez Reservoir Storage Projection
3. Monthly Water Use Comparison
4. Monthly Monitoring Report for May 2021
Item 8.l. - Page 3
San Luis Obispo County Flood Control and Water DistrictZone 3 - Lopez Project - Monthly Operations ReportMay, 20210.00Note: Deliveries are in acre feet. One acre foot = 325, 850 gallons or 43, 560 cubic feet. Safe yield is 8,730 acre feet."Year to Date" is January to present for State water, April to present for Lopez deliveries, and July to present for rainfall.399.83April to Present11.31Arroyo Grande2290Lopez Dam OperationsLake Elevation (full at 522.37 feet)476.37Storage (full at 49200 acre feet)18037Rainfall0Downstream Release (4200 acre feet/year)95.2Spillage (acre feet)0This MonthYear to Date336.720.00807.00209.72Entl.Surplus Water DeclaredUsage3097Total Available WaterLopez Water Deliveries0.00Oceano CSD303314.000.00617132.12Grover Beach800282.0069.30108221.41Pismo Beach892107.0021.4199913.33CSA 1224586.007.97331280.081260140.0036.26968.49125.0764066.77State Water Deliveries566.6945301596.00308.406126495.702116231.55Total ContractorDifference (feet)-46.00% Full36.7%Comments:1) Oceano supplied water to Canyon Crest via Arroyo Grande's Edna turn out. A total of 2.3 AF delivered to Canyon Crest wasadded to Oceano's water usage this month and 2.3 AF was subtracted from Arroyo Grande's usage this month.2) On May 12, 2021 Pismo requested to take all SW for April 2021. On May 18th, PB's SW Delivery Request was changed to 1260AF.April to Present Lopez Entitlement+Surplus Water Usage050100150200250Jul '20 Aug '20 Sep '20 Oct '20 Nov '20 Dec '20 Jan '21 Feb '21 Mar '21 Apr '21 May '21Acre FeetAGGBOCSDPBCSA12January to Present State Water Usage020406080100120140160Jul '20 Aug '20 Sep '20 Oct '20 Nov '20 Dec '20 Jan '21 Feb '21 Mar '21 Apr '21 May '21Acre FeetOCSDPBCSA12SanMigSan Miguelito54.2912016.29This Month%TotalJanuary to PresentUsageThis Month% of Annual RequestUsage% of Annual Request209.72Total Water Deliveries This Month66.7769.3161.4116.4616.29539.95Annual Request0.00Usage0.000.000.000.00%0.000.000.000.000.00399.830.00132.1221.4113.33566.690.00367.00SWP DeliveriesSWP DeliveriesChange in Storage78-153.551137.46This Month Stored State Water0.0%9.2%12.9%0.0%0.0%8.7%12.2%2.4%2.1%3.3%4.0%11.1%22.2%8.8%37.8%10.4%19.5%6.8%9.3%10.9%23.4%13.6%45.2%0.0%0.0%0.0%0.0%0.0%0.0%0.0%0.0%0.0%0.0%17.5%0.0%16.5%2.4%5.4%12.5%0.0%EntitlementSurplusUsage%Usage%EntitlementSurplusUsage%1291.01Last Month Stored State WaterSurplus Requested807.00314.00282.00107.0086.001596.00Wednesday, June 9, 2021Page 1 of 1Report printed by:AdminData entered by:D. BravoAttachment 1Item 8.l. - Page 4
San Luis Obispo County Flood Control and Water DistrictZone 3 - Lopez Project - Monthly Operations ReportMarch, 2020727.00Note: Deliveries are in acre feet. One acre foot = 325, 850 gallons or 43, 560 cubic feet. Safe yield is 8,730 acre feet."Year to Date" is January to present for State water, April to present for Lopez deliveries, and July to present for rainfall.2122.35April to Present14.31Arroyo Grande2290Lopez Dam OperationsLake Elevation (full at 522.37 feet)490.87Storage (full at 49200 acre feet)25472Rainfall5.37Downstream Release (4200 acre feet/year)207.46Spillage (acre feet)0This MonthYear to Date2736.220.00378.00139.74Entl.Surplus Water DeclaredUsage2290.00Total Available WaterLopez Water Deliveries624.35Oceano CSD30350.000.00624.35787.22Grover Beach800132.0064.00820.001297.65Pismo Beach892147.000.001297.6586.34CSA 1224540.007.19245.0097.27112023.845.92272.040.002270.00State Water Deliveries4917.914530747.00210.935277.00132.28150135.14Total ContractorDifference (feet)-31.50% Full51.8%Comments:Available Surplus Water is shown and as designated per BOS May 14, 2019 Declaration of Surplus Water. Beginning with July 2019 report, Surplus Water Requested is amount purchased by each agency. Surplus Water used is based on Surplus Water Requested. 1) Oceano supplied water to Canyon Crest via Arroyo Grande's Edna turn out. A total of 1.5 AF delivered to Canyon Crest wasadded to Oceano's water usage this month and 1.5 AF was subtracted from Arroyo Grande's usage this month.On 2/7/2020 Pismo requested the remaining 127 AF of surplus water (SurW) in addition up to 90 AF of Oceano’s SurW if needed for March, 2020. In March, Pismo used 78.65 AF of Oceano's remaining SurW. Pismo Surplus = 200 AF (original) + 127AF (Total remaining SurW) + 78.65 (Oceano's remaining SurW Requested) = 405.65 AF.San Miguelito29.091279.26This Month%TotalJanuary to PresentUsageThis Month% of Annual RequestUsage% of Annual Request139.74Total Water Deliveries This Month48.0764102.499.239.26372.79Annual Request0.00Usage48.070.0078.650.00%0.00321.350.00405.650.002122.35303.00787.22892.0086.344190.91126.72136.00SWP DeliveriesSWP DeliveriesChange in Storage1459.97This Month Stored State Water97.3%6.1%92.7%0.0%100.0%8.0%96.0%0.0%100.0%2.9%35.2%2.1%8.7%7.6%21.9%0.0%0.0%4.7%93.2%2.3%8.8%7.3%22.9%0.0%15.0%0.0%19.4%0.0%0.0%100.0%0.0%100.0%0.0%92.7%100.0%98.4%100.0%35.2%92.5%17.0%EntitlementSurplusUsage%Usage%EntitlementSurplusUsage%Last Month Stored State WaterSurplus Requested0.00321.3520.00405.650.00747.00Friday, April 3, 2020Page 1 of 1Report printed by:AdminData entered by:D. Bravo$77$&+0(17DItem 8.l. - Page 5
5.44
0.54
0.00
4.70
2.14
0.24 0.00 0.00 0.00 0.00 0.00 0.52
1.42
5.16
0.22 0.94 0.00
2.87 3.10 2.77
0.90
0.33 0.32 0.62
1.34
2.03
3.02 3.25 2.91
1.13
0.41 0.07 0.03 0.02 0.28 0.52
1.84
2.90
0.00
2.00
4.00
6.00
8.00
10.00
12.00
14.00
0
5000
10000
15000
20000
25000
30000
35000
40000
1/1/20202/1/20203/1/20204/1/20205/1/20206/1/20207/1/20208/1/20209/1/202010/1/202011/1/202012/1/20201/1/20212/1/20213/1/20214/1/20215/1/20216/1/20217/1/20218/1/20219/1/202110/1/202111/1/202112/1/20211/1/2022Storage (AF)Date
LOPEZ RESERVOIR STORAGE PROJECTION
Actual Precipitation Predicted Precipitation Actual Storage
20,000 AF Storage Projection Storage Projection (No Rain)
1. Storage projection is based on predicted rainfall from longrangeweather.com, inflow based on predicted rainfall, 20-21 downstream release requests, and municipal usage.
2. Municipal Usage is based on Jan 2010-Dec 2020 average monthly deliveries.
3. Predicted inflow is based off of historical precipitation and storage data. Antecedant moisture conditions are factored into the model.The first rainstorms after months without
rain will cause less inflow than rainstorms during the rainy season. If the average daily rainfall for the previous three months is below 1 inch the model will multiply the predicted
inflow by 0.1, if the average is above 1 inch the inflow is multiplied by 1.25.
Attachment 2
Item 8.l. - Page 6
221.5223.4132133050100150200250May‐20 May‐21Monthly Water Use ComparisonAcre FeetUsage (gpcd)Attachment 3Item 8.l. - Page 7
ATTACHMENT 4
Below is the information you have submitted for the month of May 2021. We use your
most recently submitted monthly report in our calculations.
Reporter Shane Taylor
Urban Water Supplier (Number) Arroyo Grande City of (608)
Public Water System ID(s) CA4010001
Reporting Month 5/21
County / Counties San Luis Obispo
Water Shortage Contingency Plan 0
Water Shortage Level No
Population 17636
Total Potable Water Production 223.4 AF
Commercial Agricultural Water 0 AF
Residential Use Percentage 80%
CII Water 24.6 AF
Recycled Water 0 AF
Non-revenue Water AF
Estimated R-GPCD 106.52
Qualification
State Water Resources Control Board Office of Research, Planning & Performance
Item 8.l. - Page 8