Stream Team water chemistry sites. Image: Heal the Bay (click image to explore sites)

Since 1998, the Stream Team water chemistry monitoring program has been collecting and analyzing data from sites throughout the Malibu Creek watershed.

By training and mobilizing thousands of citizen volunteers, high quality, useable data has been collected for a fraction of the cost of a public agency or an independent laboratory. The collected data is entered into a publically available, free, online database where it can be queried, viewed and downloaded.

Goals & Results

The goals of the Stream Team’s water chemistry monitoring program are:

1. Determine the sources of pollution that cause or contribute to the consistently poor water quality at Malibu Surfrider Beach.
2. Estimate the expected water quality in the watershed if development were not impacting the waterways.
3. Determine what areas or pollution sources should be targeted to improve water quality for people and wildlife.

At the conclusion of the program's volunteer monitoring component in January 2007, these goals have been met with incredible success (see sidebar at right: "Data Findings"). These findings are the result of data collected by over 5,800 volunteers since 1998.

Overall, Stream Team water chemistry data has helped establish tougher water quality standards that better protect people and wildlife in the Malibu Creek watershed and has established a precedent to implement these standards in other watersheds throughout the state.

Although volunteer monitoring is completed, professional field crew collection and ongoing analysis of water chemistry data continues to provide invaluable insight and findings about pollution in the Malibu Creek watershed. It is expected that the Stream Team water chemistry program will positively impact water quality in this region for years to come.

Monitoring — The Water Chemistry Parameters

The Stream Team water chemistry monitoring program examines the following parameters: Site conditions, Water temperature, pH, Stream flow, Dissolved oxygen (DO), Turbidity, Conductivity (Total Dissolved Solids), Phosphorus, nitrate-nitrogen & ammonia-nitrogen.

Site Conditions
The site conditions of the monitoring location aids Heal the Bay in analysis of the data. These parameters include weather conditions, air temperature presence of debris, presence of algae, and water color, appearance, and odor.

Water Temperature
Temperature of the water directly affects biological and chemical processes. Some fish species prefer colder waters than other species. Benthic macroinvertebrates will move in the stream in order to find their optimal temperature.

pH
pH is a measure of how acidic or alkaline the water is at the time of testing. The pH of a stream affects the ability of plants and wildlife to function and live. pH is measured on a scale from 1.0 to 14.0. Neutral pH is 7.0. Acidic pH is less than 7.0, and alkaline is greater than 7.0. A wide variety of aquatic animals prefer a range of 6.5-8.0 pH.

Stream Team volunteers measure stream flow. Photo: Heal the Bay (click image to enlarge)

Stream Flow
Stream flow (the volume of water that moves past a fixed point in a specific interval of time) is an important indicator of water quality. It affects the available oxygen level in water that fish and other aquatic wildlife depend on to live. Generally streams with higher flows have more oxygen available for aquatic wildlife. Stream flow also controls the amount of sediment that is transported in a stream.

Flow measurements help determine how much each subwatershed is contributing to downstream flows and the extent to which development is changing the natural hydrology in the watershed.In addition, stream flow determines how pollution is transported downstream and influences the ability of a stream to dilute pollution. Large, swift rivers have a greater ability to dilute and degrade runoff pollutants, unlike smaller streams.

Dissolved Oxygen (DO)
Aquatic organisms rely on the presence of oxygen in streams. In water, oxygen is in a dissolved form. Water temperature and altitude, time of day, and seasons can all affect the amount of dissolved oxygen. Oxygen is both produced and consumed in a stream. Because of constant churning, running water, especially in riffles, dissolves more oxygen than the still water often found in a lake or stream pool (US EPA 841-B-97-003 1997, p.139). The presence of aquatic plants also affects dissolved oxygen concentrations. Green plants release oxygen underwater during photosynthesis. Maximum amounts of DO are produced with the energy of the late afternoon sun. By early morning, the same plants may have taken up the oxygen, making levels of DO lowest at this time.

Turbidity
Turbidity is a measure of water clarity. Insoluble solids or suspended particles such as clay, silt, sand, algae, plankton and other substances affect the clarity of the water. High levels of turbidity affect the ability of steelhead trout and other aquatic organisms to survive. Water temperature is increased because suspended particles absorb more heat. Also, when turbidity is high, photosynthesis is reduced due to the decrease in the amount of light traveling through the water.

Sources of turbidity include soil erosion, waste discharge, urban runoff, eroding streambanks, large numbers of bottom feeders that stir up sediments, and excessive algal growth.

Stream Team volunteers test creek water for conductivity. Photo: Heal the Bay (click image to enlarge)

Conductivity (Total Dissolved Solids)
Conductivity measures the ability of water to pass an electrical current. Conductivity indirectly measures the presence of inorganically dissolved solids such as chloride, nitrate, sulfate, phosphate, sodium, magnesium, calcium, iron, and aluminum (Murdoch, Cheo, and O-Laughin. 1996, p. 181). These substances and sea water enhance the ability of water to conduct electricity. Also, The concentration of dissolved solids or the conductivity of streams is directly affected by the substrate or stream bottom material. In general conductivity is higher in areas with clay soils because these soils tend to dissolve in water.

Failing septic tanks, sewage spills, and agricultural runoff containing phosphates and nitrates are indicated by high conductivity measurements. Conversely, organic substances like oil, alcohol, and grease are poor conductors of electricity and will yield low conductivity measurements.

Phosphorus and nitrogen
Phosphorus and nitrogen are both nutrients occurring naturally in streams and are essential for plants and animals in an aquatic ecosystem. These nutrients originate from both naturally occurring sources and from areas of human development. Naturally occurring sources include soils, eroding rocks, and terrestrial animal and plant waste washing into the streams. Sources of nutrients from human development include wastewater treatment plants, runoff from fertilized agricultural lands, lawns, and golf courses, runoff from grazing animals, and commercial cleaning activities.

Problems occur when large amounts of phosphorous and nitrogen are introduced into the stream ecosystem. As a result, there can be excessive algal growth depleting the available oxygen in the stream that fish and other aquatic organisms depend upon.