Healthy Streams: What makes a healthy stream?

Scientists observe, measure, record, analyze, and make conclusions

What is turbidity?

Why is low turbidity important for a healthy stream?

Dr. William Trush, River EcologistMcBain and Trush, Arcata CA

If the turbidity in a stream reaches 20 NTU’s (Nephelometric Turbidity Units) for 20 straight days, the forming salmonid will not be able to see its food, will not grow to its full length, and will be unlikely to survive into adulthood.

Cuddeback Data Turbidity Mainstem Van Duzen and Grizzly Creek

Data Report Covers a Slice of Time

November 22nd, 2014 December 6th, 2014

Water Temperature

Why is water temperature important to a healthy stream?

EPA Recommended Temperature Thresholds to Protect Salmonid species and Trout

Adult migration 64-68 F (18-20 C) Incubation 55 F (13C) Juvenile Rearing 61-64 F (16-18 C) Smoltification 57-59 F (14-15 C)

Prolonged exposures of Chinook salmon to water temperatures above about 20°C (68 F) can result in a number of adverse effects, depending on the life stage (Moyle et al. 2002).

In northern California, both Welsh et al. (2001) and Hines and Ambrose (1998) found that coho salmon juveniles did not persist where the floating weekly maximum temperature exceeded 18.3° C (65 F) for any length of time.  

What is the most prevalent fish in the Van Duzen and Eel Rivers?

Introduction of exotic fish species is a major problem in some northern California rivers, especially those with serious ecological problems. Humans have induced wholesale changes in aquatic ecosystems, such as turning the Eel River into a warm shallow stream versus a deep, cold one, and then introduced exotic species well adapted to the new conditions. While the larger predatory minnow, the northern pike-minnow, is native to the Russian River, its introduction into the Eel River basin has caused major problems. 

Cuddeback Data Temperature Mainstem Van Duzen and Grizzly Creek

Grizzly Creek December 6th, 2014

What is ph

Why is ph important to a healthy stream?

pH rises and falls during the course of a hydrologic year

The North Coast Water Quality Control Board objectives for pH in the Van Duzen River are 6.5 to 8.5.

pH in Humans

The pH scale ranges from 0 to 14; pure water has a neutral pH of 7. Acids range from 0 to 7, and bases range from 7 to 14 on the scale. The website Alkalize for Health reports that human blood maintains a steady pH of 7.4, making it slightly alkaline.

Fruits and vegetables can raise your bodies pH.

Cuddeback Data PH Mainstem Van Duzen and Grizzly Creek

A Day at Grizzly Creek State Park