CC 2024-06-25_09d Monthly Water Supply and Demand
Item 9.d.
MEMORANDUM
TO: City Council
FROM: Bill Robeson, Assistant City Manager/Public Works Director
BY: Shane Taylor, Utilities Manager
SUBJECT: Monthly Water Supply and Demand Update
DATE: June 25, 2024
RECOMMENDATION:
Receive and file the Monthly Water Supply and Demand Update.
IMPACT ON FINANCIAL AND PERSONNEL RESOURCES:
Approximately two (2) hours of staff time is required to prepare the report.
BACKGROUND:
The City of Arroyo Grande’s water entitlements are calculated on a water year that begins
April 1st. The current water supply for water year 2024/2025 includes 2,290 Acre Feet
from Lopez Reservoir, the current modeled, safe yield is 357 -Acre Feet of groundwater
from the Santa Maria River Groundwater Basin, with an entitlement of 1323 Acre Feet.
An additional 160 Acre Feet of groundwater is available from the Pismo formation.
The predicted water use for 2024/2025 water year is 2,100 Acre Feet.
In May 2024, the City’s water use was 177.8 Acre Feet with a per capita use of 104 gallons
per day/per person. The residential per capita use was 80 gallons per day/per person.
There was a total of 0.08 inches of rainfall in the City in May 2024.
Attachment 3 shows current monthly water use as compared to the previous year’s
month. Staff has provided a “Commercial Usage Portion of Production” as an additional
information point.
ANALYSIS OF ISSUES:
The United States Drought Monitor, as of June 13, 2024, shows San Luis Obi spo County
is not in a drought. Rainfall for the period of July 1, 2023, through June 13, 2024, is 18.40
inches at the Corporation Yard rain gauge. Lopez Lake is at 99.7% capacity as of June
13, 2024.
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Item 9.d.
City Council
Monthly Water Supply and Demand Update
June 25, 2024
Page 2
The deep well index for the second quarter of 2024 was completed on April 17, 2024, and
is 13.81 feet above sea level, which is 6.31 feet above the threshold value. The current
deep well index is 1.48 feet higher than January 2024, and 1.58 fee t higher than April
2023.
ALTERNATIVES:
The following alternatives are provided for the Council’s consideration:
1. Receive and file the report, or
2. Provide other directions to staff.
ADVANTAGES:
The report provides the City Council and the public with the current and projected
conditions of our water supply and demand.
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.
ATTACHMENTS:
1. Monthly Operations Report
2. Lopez Reservoir Storage Projection
3. Monthly Water Use Comparison
4. Deep Well Index Levels
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29.1
171.4
100
30.2
177.8
104
0
20
40
60
80
100
120
140
160
180
200
Commercial Usage Portion of Production Acre Feet Production Usage (gpcd)
Monthly Water Use Comparison
23-May 24-May
ATTACHMENT 3
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