BASIN-USGS-COB Boulder Creek Millenium Baseline
Boulder Creek Watershed
pH Data for 2000 - Boulder Creek at 61st St.

Preliminary Data - subject to revision


Information on pH:

pH measures hydrogen concentration in water. pH is presented on a scale from 0 to 14. A solution with a pH value of 7 is neutral; a solution with a pH value less than 7 is acidic; a solution with a pH value greater than 7 is basic. Natural waters usually have a pH between 6 and 9. The scale is negatively logarithmic, so each whole number (reading downward) is ten times the preceding one (for example, pH 5.5 is 100 times as acidic as pH 7.5). The pH of natural waters can be made acidic or basic by human activities. For example, coal-burning power plants and heavy automobile traffic can produce nitrous oxides and sulfur dioxide, making the rain and snow highly acidic.

More general information about pH
Factors affecting pH
Standards regarding pH
Interpretation of Boulder Creek pH data
Data Source: USGS Aqueous Organic Carbon Study
Point of Contact: Larry Barber
Collection and Analysis notes

Monitoring site information:
BC-61 Map
  • Location: Boulder Creek at 61st St.
  • Name: BC-61
  • Type: Composite
  • Frequency: SemiAnnual
  • Longitude: 105 ° W 12'
  • Latitude: 40 ° N 22'
  • Elevation: 5160 feet asl
  • Site photo
Downstream Site: Boulder Creek at 30th St.
Upstream Site: Boulder Creek above WW Plant

Date pH
stnd units
June, 2000 7.67
October, 2000 9.25
*value below detection limit:
Detection Limit (if available) NA

Preliminary Data - subject to revision

Select on the parameter name to view all pH time series plots on the basin map. Select on the table date to view stream pH profiles observed on that date. Select here to view all parameters at this site.

Return to the BASIN water quality catalog

Return to the BASIN environmental data catalog


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