The average DO is between 8.27 ppm and 9.75 ppm for all sites. DO levels are likely to increase through the day as temperatures rise and drive photosynthesis. Turbidity Turbidity is a measure of the amount of suspended particles in the water. Watersheds in general have a natural turbidity level with inputs from natural erosion, organic decay and algae. There has been no determination of the natural turbidity level in most of the local watersheds in Santa Cruz County.
Turbidity can be an indicator of erosion, excessive nutrient loading and algal growth.
As the pH increases, water becomes more acidic and as water become more basic, the pH increases. Changes in pH may also alter the concentrations of other substances in water to a more toxic form. In fresh water, increasing temperature decreases pH. For the Central Coast Region it is recommended that pH not be depressed below 6.5 nor raised above 8.5 for waters that are designated municipal and domestic water supply, water contact recreation, and non-contact water recreation. Soquel Creek is designated for these uses. For waters that support cold freshwater habitat the pH should not be below 7.0 nor raised above 8.5.