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Monitoring Schedules (new format)

Water System No. : CA1910142 Federal Type : C
Water System Name : GSWC-SAN DIMAS State Type : C
Principal County Served : LOS ANGELES Primary Source : SWP
Status : A Activity Date : 03-22-1979
Distribution System Classification : D5 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
Monitoring Schedule for Individual Sampling Points
Old PS Codes New PS Codes Facility ID Sample Point ID Sample Point Name Status
1910142-003 CA1910142_003_003 003 003 ARTESIA WELL 03 A
1910142-013 CA1910142_013_013 013 013 HIGHWAY WELL 01 A
1910142-014 CA1910142_014_014 014 014 MALONE A
1910142-016 CA1910142_016_016 016 016 COLUMBIA RESERVOIR - INFLUENT RAW A
1910142-023 CA1910142_023_023 023 023 TVMWD CONNECTION PM7 - TREATED A
1910142-024 CA1910142_024_024 024 024 TVMWD CONNECTION PM16 - TREATED A
1910142-025 CA1910142_025_025 025 025 CIC CONNECTION @ CIENEGA AVE+JENNIFER AV A
1910142-026 CA1910142_026_026 026 026 MALONE FOREBAY - NO3 BLEND, EFFLUENT A
1910142-027 CA1910142_027_027 027 027 TVMWD CONNECTION PM12 - TREATED A
1910142-038 CA1910142_039_038 039 038 COMBINED RAW INFLUENT TO COLUMBIA TREAT A
1910142-039 CA1910142_039_039 039 039 COMBINED IX EFFLUENT FROM COLUMBIA TREAT A
1910142-040 CA1910142_040_040 040 040 COLUMBIA TREATMENT PLANT BLENDED EFF. A
1910142-049 CA1910142_049_049 049 049 HIGHWAY NITRATE IX COMBINED EFFLUENT A
1910142-041 CA1910142_050_041 050 041 HIGHWAY PERCHLORATE IX VESSEL A 50% PORT A
1910142-042 CA1910142_050_042 050 042 HIGHWAY PERCHLORATE IX VESSEL A 75% PORT A
1910142-043 CA1910142_050_043 050 043 HIGHWAY PERCHLORATE IX VESSEL A EFFLUENT A
1910142-044 CA1910142_050_044 050 044 HIGHWAY PERCHLORATE IX VESSEL B 50% PORT A
1910142-045 CA1910142_050_045 050 045 HIGHWAY PERCHLORATE IX VESSEL B 75% PORT A
1910142-046 CA1910142_050_046 050 046 HIGHWAY PERCHLORATE IX VESSEL B EFFLUENT A
1910142-047 CA1910142_050_047 050 047 HIGHWAY NITRATE IX UNIT A EFFLUENT A
1910142-048 CA1910142_050_048 050 048 HIGHWAY NITRATE IX UNIT B EFFLUENT A
1910142-050 CA1910142_050_050 050 050 COMBINED RAW INFLUENT TO HIGHWAY TREAT A
1910142-052 CA1910142_050_052 050 052 HIGHWAY PERCHLORATE IX VESSEL A 25% PORT A
1910142-053 CA1910142_050_053 050 053 HIGHWAY PERCHLORATE IX VESSEL B 25% PORT A
1910142-051 CA1910142_051_051 051 051 HIGHWAY WELL 02 A
1910142-055 CA1910142_055_055 055 055 WALNUT VALLEY W.D. CONNECTION A
1910142-800 CA1910142_DST_800 DST 800 SITE 1-1...* A
1910142-801 CA1910142_DST_801 DST 801 SITE 2-1...* A
1910142-802 CA1910142_DST_802 DST 802 SITE3-VI...* A
1910142-803 CA1910142_DST_803 DST 803 SITE 4-1...* A
1910142-804 CA1910142_DST_804 DST 804 SITE 5-1...* A
1910142-805 CA1910142_DST_805 DST 805 SITE 6-1...* A
1910142-806 CA1910142_DST_806 DST 806 SITE 7-3...* A
1910142-807 CA1910142_DST_807 DST 807 SITE 8-2...* A
1910142-LCR CA1910142_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.