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Monitoring Results for Individual Sampling Points
(From 2011 to present only,
for prior to 2011 results please go to EDT Download Page)

Water System No. : CA1910223 Federal Type : C
Water System Name : GSWC-SOUTH SAN GABRIEL State Type : C
Principal County Served : LOS ANGELES Primary Source : SWP
Status : A Activity Date : 01-01-1976
Distribution System Classification : D4 Max Treatment Plant Classification : T2

NOTICE TO USERS OF THE DATABASE: Users of this database should use care in interpreting these data. Data that does not meet Division of Drinking Water (DDW) data quality objectives is not included and the provided data may not be representative of water served by a water system. For example, the presence of a contaminant in a particular source of water at a given concentration does not necessarily mean that the water from that source was served by the water system to its customers, or, if served, that the contaminant was present at that concentration. Water systems may not use certain sources or may treat or blend them prior to serving the water to customers.

Questions about contaminants in particular sources are best addressed by the specific public water system, or by the associated DDW district office.

The Division of Drinking Water's (DDW's) drinking water quality monitoring schedules identify upcoming required testing of drinking water for water systems in California. These documents should not be used for determining whether water systems are in compliance with monitoring requirements. The purpose for providing these monitoring schedules is to allow water systems to verify that their sampling and analyses have been incorporated into the DDW database and to identify upcoming required monitoring/sampling events.

Notes for Water Systems:
1. The monitoring notification documents should be considered "draft," in that they will change with subsequent updates, and as monitoring data are submitted, or as monitoring schedules are revised .
2. The monitoring notification documents are derived from the DDW Water Quality database and from schedules maintained by DDW districts.
3. If your upcoming monitoring or your data identified as "DUE" are not in agreement with this document, or if your have been advised of any increased monitoring that is not reflected in the report for a particular source, please contact your District Engineer or LPA representative. For a map of the districts, please click here.
4. If your notification report for a source is blank, this does not necessarily indicate compliance with all monitoring requirements.
5. These notification reports may not reflect compliance with initial monitoring for newly regulated constituents, or constituents that require special monitoring frequencies. For example, the DDW database is unable to accurately forecast the vulnerable non-volatile synthetic organic chemical (SOC) frequency for large water systems serving over 3,300 people of 2 quarters every 3 years.
5a. For radionuclide compliance monitoring, a gross alpha (GA) particle activity measurement may be substituted for other measurements when the assigned value is less than 5 pCi/L. The assigned value is calculated by adding 0.84 of the counting error (CE) to the gross alpha result (GA + 0.84xCE). If the assigned value is greater than 5 pCi/L, then the water sample must be analyzed for uranium per Section 64442, Article 5, Chapter 15, Division 4, Title 22 of the California Code of Regulations. In addition, if the difference between the assigned value and the uranium measurement [GA + (0.84 x CE) - U] is greater than 5 pCi/L, analysis for Radium-226 and Radium-228 is required. If you have specific questions, contact your DDW District Office.
6. Some Nitrate (as N) results under storet code 00618, will have a result of �N/A� which stands for �Not Applicable.� This stems from the change in regulation requiring that all nitrate sampling be reported as Nitrate (as N) starting January 1, 2016. Prior nitrate sampling was reported as Nitrate (as NO3). With this change in nitrate reporting requirements, the monitoring schedules have captured the last date of Nitrate (as NO3) sampling and applied it to Nitrate (as N) in determining the next due date [unless there have been Nitrate (as N) samples collected]. The Nitrate (as NO3) result, however, does not carry over to Nitrate (as N) which is why there may be a notation in the �Constituent Identification� column to reference storet code 71850 for the last nitrate result. In these instances, the �Constituent Identification� column will say, �NITRATE (as N) � [see 71850].� Any questions should be referred to your District Engineer.  
Test Legends:
  • PS Code = Primary Station Code; used by laboratories to upload water quality data
  • Old PS Code = (Water System Number)-(Sample Point ID)
  • New PS Code = (Water System Number)_(Facility ID)_(Sampling Point ID) to be used by laboratories to upload water quality data when CLIP (California Laboratory Intake Portal) is implemented
  • Facility Status: A = Active; P = Proposed
  • Certain PS Codes have been removed from this table as they are not intended to have water quality data electronically reported. As an example, a water system may have a PS Code to represent Well 01 and another PS Code to represent Well 01 Chlorination. However, water quality data should only be reported to the PS Code for Well 01. The PS Code for Well 01 Chlorination would be removed from the list to avoid confusion in uploading data. If you notice that a PS Code is missing from the list that may be needed for uploading water quality data, please contact your District Office or Local County Primacy Agency.

Click to hide / show columns: Old PS Code | New PS Code | Facility ID | Sample Point ID | Sample Point Name | Status

Monitoring Schedules for All Sampling Points
Water System Sampling Points
Old PS Codes New PS Codes Facility ID Sample Point ID Sample Point Name Status
1910223-004 CA1910223_004_004 004 004 SAN GABRIEL WELL 01 - ACTIVE A
1910223-005 CA1910223_005_005 005 005 SAN GABRIEL WELL 02 - ACTIVE A
1910223-009 CA1910223_009_009 009 009 SAXON WELL 04 - ACTIVE A
1910223-022 CA1910223_022_022 022 022 SGP FINAL EFFLUENT & BEFORE PT.OR INTRO A
1910223-010 CA1910223_028_010 028 010 A1-50 PERCENT PORT A
1910223-011 CA1910223_028_011 028 011 B1-50 PERCENT PORT A
1910223-012 CA1910223_028_012 028 012 C1-50 PERCENT PORT A
1910223-013 CA1910223_028_013 028 013 A1-75 PERCENT PORT A
1910223-014 CA1910223_028_014 028 014 B1-75 PERCENT PORT A
1910223-015 CA1910223_028_015 028 015 C1-75 PERCENT PORT A
1910223-016 CA1910223_028_016 028 016 A1-EFFLUENT PORT A
1910223-017 CA1910223_028_017 028 017 B1 - EFFLUENT PORT A
1910223-018 CA1910223_028_018 028 018 C1 - EFFLUENT PORT A
1910223-019 CA1910223_028_019 028 019 A2 - EFFLUENT PORT A
1910223-020 CA1910223_028_020 028 020 B2 - EFFLUENT PORT A
1910223-021 CA1910223_028_021 028 021 C2 - EFFLUENT PORT A
1910223-023 CA1910223_028_023 028 023 A2-50 PERCENT PORT A
1910223-024 CA1910223_028_024 028 024 B2-50 PERCENT PORT A
1910223-025 CA1910223_028_025 028 025 C2-50 PERCENT PORT A
1910223-026 CA1910223_028_026 028 026 A2-75 PERCENT PORT A
1910223-027 CA1910223_028_027 028 027 B2-75 PERCENT PORT A
1910223-028 CA1910223_028_028 028 028 C2-75 PERCENT PORT A
1910223-036 CA1910223_036_036 036 036 MWD (USG-1) CONNECTION-TREATED A
1910223-037 CA1910223_037_037 037 037 GARVEY WELL 3 - ACTIVE A
1910223-038 CA1910223_045_038 045 038 GARVEY TP - A25% PORT A
1910223-039 CA1910223_045_039 045 039 GARVEY TP - A50% PORT A
1910223-040 CA1910223_045_040 045 040 GARVEY TP - A75% PORT A
1910223-041 CA1910223_045_041 045 041 GARVEY TP - A FINAL EFFLUENT A
1910223-042 CA1910223_045_042 045 042 GARVEY TP - B25% PORT A
1910223-043 CA1910223_045_043 045 043 GARVEY TP - B50% PORT A
1910223-044 CA1910223_045_044 045 044 GARVEY TP - B75% PORT A
1910223-045 CA1910223_045_045 045 045 GARVEY TP - B FINAL EFFLUENT A
1910223-046 CA1910223_046_046 046 046 GARVEY TP - COMBINED EFFLUENT A
1910223-800 CA1910223_DST_800 DST 800 SITE 1-7...* A
1910223-801 CA1910223_DST_801 DST 801 SITE 2-7...* A
1910223-802 CA1910223_DST_802 DST 802 SITE 3-7...* A
1910223-803 CA1910223_DST_803 DST 803 SITE 4-7...* A
1910223-LCR CA1910223_DST_LCR DST LCR Lead and Copper Sample Sites ** A
Old PS Codes Old PS Codes Facility ID Sample Point ID Sample Point Name Status
*Please refer to the Stage 2 DBP Monitoring Plan Approval Letter for full sample point names.
**Please use this PS Code for all lead and copper samples.