Urban Streams Monitoring Program

The Urban Streams Monitoring Program was developed to obtain baseline water quality data for streams in the city of Bellingham. Data is used to detect changes in these streams. The program is conducted by the Public Works Operations Division. The city has carried out monthly water quality monitoring of streams since 1990. Currently monitoring takes place at 18 sites, on 11 streams: Whatcom, Hanna, Cemetery, Lincoln, Fever, Padden, Connelly, Chuckanut, Squalicum, Baker, and Silver Creeks.

Water Quality Parameters Measured

Fecal coliform bacteria—inhabitants of the digestive tracts of warm-blooded animals. While fecal coliforms generally do not cause illnesses themselves, they can indicate that other illness–causing bacteria or viruses from fecal sources such as septic systems, sewer lines, pets, birds, and other wildlife may be present in the water.

Temperature—many fish species need cooler temperatures to survive. Sockeye salmon eggs will not survive above about 13oC (64oF). Human activities, including removal of streamside trees and other vegetation, can lead to higher temperatures in streams.

Dissolved oxygen—living things in streams need oxygen to survive. Dissolved oxygen is the amount of oxygen dissolved in water. If dissolved oxygen becomes too low there may not enough oxygen to sustain aquatic life. Salmon need a minimum of 7.5 mg/L dissolved oxygen to survive. Decreases in dissolved oxygen can be caused by increases in temperature (warm water will not hold as much dissolved oxygen as cool water), and inputs of pollutants that rob the water of oxygen.

pH—most living things in water need a pH that is close to neutral (around 7.0). Natural water usually has a pH between 6.5 and 8.0. Changes in pH, often an indication of pollutants, can seriously affect the health and diversity of aquatic life in streams. Fish species such as salmon are very sensitive to pH, especially in the early life stages. For example, when pH gets below 6.5 salmon eggs and newly hatched salmon begin to die; below 5.5, few survive.

Turbidity—used to estimate the amount of suspended materials in water. High turbidities, usually caused by streamside or bank erosion, can clog gills, smother living things, cover spawning beds, and destroy habitat. Salmon growth is reduced and gill tissue damaged after only 5 to 10 days of exposure to a turbidity level of 25 NTU (Nephelometric Turbidity Unit). Removal of streamside trees and other vegetation can increase erosion.

Conductivity—measures the ability of water to conduct an electric current and is directly related to the total dissolved ions in the water. Conductivity can be used as an overall indication of water quality. Higher conductivities may be a sign of contamination in the water.


City of Bellingham laboratory staff follow strict protocols for collecting and processing samples. Field instruments are calibrated and maintained also following strict protocols. Some of the quality control/quality assurance guidelines include duplicate samples and measurements and quality control standards. Data are carefully examined and anomalous values investigated before publication.