Click to Home
Go To Search
Urban Forest
CommunityBusinessVisitorsGovernmentEnvironment
San Jose Home
Water Quality Data
The hexavalent chromium MCL was invalidated during the 2017 calendar year, but public water systems are required to report the information collected prior to the MCL being invalidated.
<< Previous 6 of 8 Next >>  
2017 Water Quality Data

Water at various locations in the distribution system is tested by certified City staff and a private, state-certified laboratory using the latest testing procedures and equipment. During 2017, numerous tests were conducted on samples taken from the distribution system. In addition to these tests, the SCVWD and SFPUC perform their own water quality analyses of the source and treated water.

Test results from the distribution system and source water analyses are shown in the table at right. Some of the data, though representative, are more than one year old. SWRCB allows monitoring for some contaminants less than once per year since the concentrations of these contaminants do not change frequently.

Lab analysis was also performed for many constituents other than those listed in the tables; only those chemicals detected in the tap water are shown. For a complete list of all the chemicals analyzed or any questions about this report, please contact a Water Quality Engineer at 408-277-3671.


Primary Drinking Water Standards — Public Health-Related Standards
Parameter Unit MCL
(MRDL) [AL]
PHG
(MCLG) [MRDLG]
Evergreen
(SCVWD Treated 
Water)
Evergreen
(Groundwater) 
Edenvale**
(Groundwater)
Coyote Valley
(Groundwater)
North San José/Alviso
(SFPUC Treated Water)
North San José/Alviso
(Groundwater)
Typical Source
Inorganic Chemicals
Average Range Average
 Range  
Average Range Average Range Average Range Average Range  
Aluminum ppm 1 0.6 0.10 ND - 0.12  0.12
 ND - 0.5
ND ND NDc ND ND ND - 0.1 ND ND 1
Arsenic
ppb
10
0.004
ND ND ND ND - 2.1 ND ND NDc ND ND ND ND ND 6, 12  
Barium ppm 1 2 ND ND 0.2 0.2 - 0.2 0.15 0.14 - 0.15 NDc ND ND ND 0.2 0.2 - 0.2 1
Fluoride ppm 2 1 0.7 0.7 - 0.8 0.2 0.2 - 0.2 0.2 0.2 - 0.2 0.15c  0.15 - 0.15 0.7 0.5 - 0.9 0.1 ND - 0.1 1, 2
Hexavalent Chromiumd ppb 10 0.02 ND ND 4.3 3.5 - 5.9 5.7 4.7 - 6.6 4.5c 4.4 - 4.5 ND ND ND ND 1, 12
Nitrate (as N) ppm 10 10 0.4 ND - 0.7 2.4 2.3 - 2.4 2.2 1.5 - 2.9 0.6 0.5 - 0.6 ND ND 1.9 ND - 3.3 1, 3
Selenium ppb 50 30 ND ND ND ND ND ND ND ND ND ND ND ND - 6 6  
Organic Chemicals             
Total Trihalomethanese ppb 80 NS 32 25 - 38 NA NA NA NA NA NA 59 35 - 62 NA NA 4
Total Haloacetic Acidse ppb 60 NS 9 ND - 14 NA NA NA NA NA NA 46 10 - 62 NA NA 4
Total Organic Carbon ppm TT NS 2.1 1.7 - 2.2 NA NA NA NA NA NA 2.4 1.0 - 3.7 NA NA 15
Disinfection            
Chloramine (as chlorine)a ppm (4) [4] 2.2 0.01 - 3.8 NA NA NA NA - 3.4 NA NA - 1.3* 2.8 1.8 - 3.9 NA NA 5
Microbiological            
Cryptosporidium oocysts/L TT 0 ND ND - 0.1 NA NA NA NA NA NA ND ND NA NA 6
Giardia lamblia cyst/L TT (0) ND ND - 0.2 NA NA NA NA NA NA 0.05 ND - 0.22 NA NA 6
  Highest
%
Range Highest 
%
 
Range
Highest
%
Range Highest
%
Range Highest # Range Highest # Range  
Total Coliforma % pos
per month
5 (0) 0 0 0 0 0 0 0 0 NA NA NA NA 6
# pos
per month
1 (0) NA NA NA NA NA NA NA NA 0 0 0 0 6
Clarity            
Turbidity
(unfiltered sources)
NTU 5 NS NA NA NA NA NA NA NA Highest Level
= 2.7
NA NA 7
Turbidity
(filtered sources)
NTU 1 NS Highest Level
= 0.23f
NA NA NA NA NA NA Highest Level
= 1f
NA NA 7
Lead and Copper 90th Percentile (# Samples Exceeding AL)
Leadb ppb [15] 0.2 ND (0 of 54) ND (0 of 54) ND (0 of 54) ND (0 of 31) 8
Copperb ppb [1300] 300 190 (0 of 54) 190 (0 of 54) 190 (0 of 54) ND (0 of 31) 8

Secondary Drinking Water Standards — Aesthetic Standards
 Parameter Unit SMCL Evergreen
(SCVWD Treated Water)
Evergreen
(Groundwater) 
Edenvale
(Groundwater)
Coyote Valley
(Groundwater)
North San José/Alviso
(SFPUC Treated Water)
North San José
(Groundwater)
Typical Source
Average Range Average  Range 
Average Range Average Range Average Range Average Range  
Chloride ppm 500 64 24 - 79 53 51 - 56 47 46 - 48 43c 40 - 46 9 ND - 17 38 29 - 46 9, 10
Color CU 15 ND ND 6 ND - 12 3 ND - 5 5c ND - 9 ND ND - 13 5 ND - 10 11
Iron ppm 0.3 ND ND ND ND ND ND - 0.1 NDc ND ND ND ND ND 1
Odor TON 3 1 1 - 1 ND ND ND ND NDc ND ND ND ND ND 11
Specific Conductance μS/cm 1600 476 211 - 525 783 760 - 810 605 590 - 620 515c 510 - 520 168 29 - 256 665 570 - 760 10, 14
Sulfate ppm 500 46 17 - 51 72 67 - 79 51 49 - 53 38c 37 - 39 17 0.9 - 34 67 46 - 87 9, 12
Total Dissolved Solids ppm 1000 248 120 - 270 520 500 - 560 395 390 - 400 335c 320 - 350 76 ND - 122 465 360 - 570 9
Turbidity NTU 5 ND ND 1.3 ND - 4.6 0.7 0.2 - 1.2 0.6c 0.4 - 0.8 0.4 0.1 - 1 0.31 0.24 - 0.37 7

Other Water Quality Parameters
Parameter Unit MCL

Evergreen
(SCVWD Treated Water)

Evergreen
(Groundwater)
Edenvale
(Groundwater)
Coyote Valley
(Groundwater)
North San José/Alviso
(SFPUC Treated Water)
North San José
(Groundwater)
Average Range  Average
 Range  Average Range Average Range Average Range Average Range
Boron ppb NS ND ND - 123 NA NA NA NA NA NA ND ND - 203 NA NA
Calcium ppm NS 19 10 - 25 63 57 - 71 47 39 - 55 42c 41 - 43 16 2 - 31 80 61 - 98
Hardness
(as CaCO3)g
ppm NS 98 48 - 114 388 375 - 401 304 303 - 304 241c 235 - 247 51 7 - 82 307 226 - 387
Magnesium ppm NS 11 5 - 13 57 53 - 63 46 40 - 51 33c 31 - 35 6.2 0.2 - 11 26 18 - 34
pH - NS 7.9 7.7 - 8 7.2 7.2 - 7.3 7.4 7.3 - 7.4 7.4c 7.4 - 7.5 9.2 7.4 - 9.8 7.4 6.9 - 7.9
Potassium ppm NS 3.1 1.5 - 3.3 1.3 1.2 - 1.4 ND ND 1c 1 - 1 1 0.2 - 2 1.5 1.3 - 1.7
Silica ppm NS 13 11 - 13 NA NA NA NA NA NA 7.6 4.6 - 12 NA NA
Sodium ppm NS 49 21 - 52 41 35 - 48 29 28 - 30 20c 18 - 22 18 2.3 - 31 38 33 - 42
Total Alkalinity (as CaCO3 ppm NS 81 45 - 99 338 320 - 360 250 240 - 260 180c 180 - 180 52 6 - 131 260 220 - 300


* Temporary chlorination was performed during April 2017 and October 2017 for maintenance purposes. No chlorine was present in the service area during the remainder of the year.
** SCVWD treated surface water was delivered to the Edenvale distribution system from 1/1/2017 - 12/13/2017. Refer to the Evergreen data column in this table for details on the quality of that water supply.
 
Notes:
  1. Distribution system data in 2017.
  2. Distribution system data in 2015.
  3. Well data from 2016 and 2017.
  4. The hexavalent chromium MCL was invalidated during the 2017
    calendar year, but public water systems are required to report the
    information collected prior to the MCL being invalidated.
  5. Distribution system data in 2017. Running averages are
    calculated from data for previous quarters that are not
    shown in this table.
  6. Filtered water turbidity required to be < 0.3 NTU in 95%
    of samples. All filtered water sources met this standard.
  7. To convert hardness from ppm to grains per gallon, divide
    by 17.1.

Typical Sources in Drinking Water:
  1. Erosion of natural deposits
  2. Water additive that promotes strong teeth
  3. Runoff and leaching from fertilizers
  4. By-product of drinking water disinfection
  5. Added for disinfection
  6. Naturally present in the environment
  7. Soil runoff
  8. Internal corrosion of household plumbing systems
  9. Runoff and leaching of natural deposits
  10. Seawater influence
  1. Naturally-occurring organic material
  2. Industrial waste
  3. Industrial discharges
  4. Substances forming ions in water
  5. Various natural and man made sources
  6. Naturally occurring
  7. Human/animal fecal waste
  8. Discharge from steel and pulp mills, chrome plating
  9. Discharge from metal factories

Definitions:
AL (Regulatory Action Level) The concentration of a contaminant which, if exceeded, triggers treatment or other requirements that a water system must follow.
MCL (Maximum Contaminant Level) The highest level of a contaminant that is allowed in drinking water. Primary MCLs are set as close to the PHGs (or MCLGs) as is economically and technically feasible.
Secondary MCLs are set to protect the odor, taste, and appearance of drinking water.
MCLG (Maximum Contaminant Level Goal) The level of a contaminant in drinking water below which there is no known or expected risk to health. MCLGs are set by the USEPA.
MRDL (Maximum Residual Disinfectant Level) The highest level of a disinfectant allowed in drinking water. There is convincing evidence that addition of a disinfectant is necessary for control of microbial contaminants.
MRDLG (Maximum Residual Disinfectant Level Goal) The level of a drinking water disinfectant below which there is no known or expected risk to health. MRDLGs do not reflect the benefits of the use of disinfectants to control microbial contaminants.
NL (Notification Level) Health-based advisory levels established by the SWRCB for chemicals in drinking water that lack maximum contaminant levels.
PDWS (Primary Drinking Water Standard)  MCLs and MRDLs for contaminants that affect health along with their monitoring, reporting, and water treatment requirements.
PHG (Public Health Goal) The level of a contaminant in drinking water below which there is no known or expected risk to health. PHGs are set by the California Environmental Protection Agency.
Source Water Raw water that has not been treated to meet drinking water standards.
Treated Water Water that has been treated to meet USEPA and SWRCB drinking water standards.
Treatment Technique  A required process intended to reduce the level of a contaminant in drinking water.

Abbreviations:
 <  less than
 AL  Action Level
 CU  Color Unit
 NA  Not Applicable
 ND  Not Detected
 NS  No Standard
 NTU  Nephelometric Turbidity Units
 pCi/L  pico Curies per liter
 ppb  parts-per-billion (equals 1 microgram per liter (µg/L))
 ppm  parts-per-million (equals 1 milligram per liter (mg/L))
 TON  Threshold Odor Number
 TT  Treatment Technique
 µS/cm  microSiemens per centimeter

<< Previous 6 of 8 Next >>