Watershed Quality Monitor

A new watershed monitor has been installed on Buck Creek that collects real time data for depth, temperature, turbidity, electrical conductivity (salt levels).  Calvin Christian High School teacher and FOBC Board member, Mike Hoekwater, will be maintaining this amazing device and use the data with his classes. Please share this website with other educators/interested folks to access this data: http://monitormywatershed.org/sites/BuckCreekWA/

Following is some information that may be useful to help understand the data the monitor provides:

Water Depth

Water depth is measured in millimeters using a pressure transducer, which measures water pressure. The deeper the water, the more pressure it exerts. Water depth measurements can be translated to discharge through development of a rating curve, which requires a series of discharge measurements at varying flows allowing for the development of a relationship between depth and discharge.

Discharge, or stream flow, is the volume of water that moves over a designated point over a fixed period of time. It is often expressed as cubic feet per second (ft3/sec). Access to streamflow data allows for more accurate interpretation of water-quality data. An observed trend in water quality—for example, increasing concentrations of a contaminant in a stream over a six-month period—may indicate an actual water-quality change or may be the indirect result of differences in the distribution of flow volumes when the water samples were collected.

Temperature

In general, trout prefer water temperature to not exceed 20-22 degrees C. To breath, trout utilize oxygen that is dissolved in water (dissolved oxygen). The colder the water the more dissolved oxygen is present. The warmer the water the less dissolved oxygen is present.

Temperature is expressed in degrees Celsius. To convert a Celsius measurement to Fahrenheit use the formula below.

F = (C x 1.8) + 32 ….  So for a measurement of 16 degrees Celsius… F = (16 x 1.8) + 32 >>> F = 60.8

Michigan water quality regulations dictate that streams capable of supporting coldwater species should not receive a heat load that would cause either of the following occurrences:

(a) Increase the temperature of the receiving waters at the edge of the mixing zone more than 2 degrees Fahrenheit above the existing natural water temperature.

(b) Increase the temperature of the receiving waters at the edge of the mixing zone to temperatures greater than the following monthly maximum temperatures:

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
38 38 43 54 65 68 68 68 63 56 48 40

Electrical Conductivity

Electrical conductivity is a measurement of the ability of water to pass an electrical current and is expressed in microsiemens per centimeter (μS/cm). The conductivity of water is affected by the presence of dissolved inorganic ions, such as calcium, chloride and magnesium, which enter the water through erosion of rocks and soils, as well as various human impacts such as urban runoff and agriculture. Every stream has a baseline conductivity, which can vary widely from stream to stream ranging from 50 to 1500 μS/cm. Think of conductivity as a tool for a rough assessment of stream health, like a doctor taking your temperature. A rapid increase in conductivity indicates that there is something in the stream that was not there previously, which may signify a water quality problem. Generally, as flow increases conductivity will decrease since rainwater has a low conductivity and dilutes higher conductivity groundwater. An increase in conductivity corresponding to an increase in streamflow indicates that rainwater is picking up some type of ion before entering the stream. A common cause of high conductivity readings is road salt washing into a stream during snowmelt or a rain event. Conductivity will also vary with temperature, so readings displayed on monitormywatershed.org are standardized to 25 degrees C. There are no numeric standards for conductivity in Michigan. High conductivity has the potential to negatively affect aquatic life, especially benthic macroinvertebrates. Starting at approximately 500 μS/cm, some macroinvertebrate species are negatively impacted. Trout growth may be impacted when conductivity exceeds ~2,150 μS/cm.

Turbidity

Turbidity measures the ability of light to pass through water. The higher the turbidity the cloudier the water. Measured in Nephalometric Turbidity Units (NTU) turbidity is primarily affected by sediments and other material suspended in the water column. There are no numeric standards for turbidity in Michigan. Narrative standards state that “The surface waters of the state shall not have any of the following physical properties in unnatural quantities which are or may become injurious to any designated use.” Designated uses include agricultural, industrial water supply, public water supply (at point of intake), navigation, warm water and/or coldwater fishery, other indigenous aquatic life and wildlife support, and partial and total body contact recreation. See the table below for some thresholds to ecosystem impacts.

Some information collected from:

Birtwell, Farrell, and Jonsson 2008: The validity of including turbidity criteria for aquatic resource protection in land development guideline