NCMA 2024 Annual Report
Ag Representatives
Meeting
GSI Water Solutions, Inc.
July 24, 2025
Presentation
Overview
Introduction
Goal: Coordination with Ag Reps
2024 Hydrology (Precipitation and
Evapotranspiration)
2024 Water Use
Groundwater Basin Conditions
Key Findings
2 Santa Maria
Groundwater
Basin (SMGB)
Three management areas:
1. Northern Cities Management Area
(NCMA)
2. Nipomo Mesa Management Area
(NMMA)
3. Santa Maria Valley Management
Area (SMVMA)
Court ordered monitoring program
and Annual Report (Santa Maria
Groundwater Basin Adjudication)
3 Northern Cities
Management
Area
City of Arroyo Grande
City of Pismo Beach
City of Grover Beach
Oceano Community Services District
Private Users
Agricultural Irrigation
Rural Use
4 2024 Hydrology 5
Average annual rainfall –
15.6 inches
Rainfall in 2024: 15.42 inches
Above average rainfall in
4 of 12 months
ETo1 exceeded rainfall in 5 of 12
months
1 – Reference Evapotranspiration (ETo)
recorded at Nipomo CIMIS Station
NCMA
Agricultural
Land in 2024
6 7
Estimated Agricultural Pumpage in 2024
NCMA
Pumpage
from
SMGB in
2024
8 NCMA
Total
Water Use
in 2024
9 Historical
NCMA
Production/
Delivery
10 Locations of
Monitoring
Wells
5 coastal well clusters
15 wells total
Deep Well Index:
Average of water levels in
3 coastal wells:
(24B03, 30F03, and 30N02)
11 Groundwater
Levels
Spring 2024
12 Yellow Contours:
Alluvial Aquifer (Cienega Valley)
Blue Contours:
Deep Aquifer System
Groundwater
Levels
Fall 2024
13 Yellow Contours:
Alluvial Aquifer (Cienega Valley)
Blue Contours:
Deep Aquifer System
Historical
Deep
Well
Index
14 Deep Well Index at
end of 2024 was 11.5 ft,
4 feet higher than
threshold value.
Key Findings
Total 2024 NCMA Water Use – 7,783 AF
(7,403 AF in 2023)
Lopez Lake – 4,173 AF (3,493 AF in 2023)
State Water Project – 661 AF
(1,213 AF in 2023)
Groundwater – 2,949 AF (2,697 AF in 2023)
Other Groundwater – 0 AF
(0 AF in 2023)
Total Urban Water Use – 5,356 AF
(second lowest in 20 years!)
Total Agricultural Irrigation – 2,307 AF
Groundwater pumping is 31% of 9,500 AFY safe
yield
Estimated increase of 530 AF of groundwater in
storage (April 2023 to April 2024)
15 Questions?