The PWA Mark 1 Telemeter and Webmap

The PWA Mk1 Telemeter and associated computational methods assures fish-friendly surface water diversions that are compliant with the California State Water Resources Control Board's (SWRCB) Policy for Maintaining Instream Flows in Northern California Coastal Streams (ISFP) and mitigate the cumulative effects of water diversions so that they operate in compliance with the objectives of the SWRCB and California Department of Fish and Wildlife. The PWA Mk1 Telemeter monitors stream stage and water temperature (illustrated by the following graph) and records the data to the AT&T M2X Cloud, which can be graphed on a website or downloaded to a database archive.

The PWA Mk1 Telemeter reads and uploads stream stage as measured by an ultrasonic sensor and water temperature from an immersed probe on a periodic basis, nominally, once per hour. A site-specific stage-discharge relationship is used to determine discharge from stream stage measurements. The networked PWA Mk1 Telemeter will control diversion works so they operate only when in compliance with the ISFP.

As the gauged stream flow recedes towards the low-flow threshold, all of the water diversions in a given sub-watershed will be operated in a sequential manner that prevents simultaneous diversions from cumulatively dewatering a stream. In this mode, individual diversions will be sequenced in time and duration in accordance with their associated water rights license, permit, seniority, and water allocation. For points of diversion where the diversion capacity exceeds sustainable levels, pumps can be pulsed to reduce diversion rates to maintain environmentally acceptable instream flows.

The PWA Mk1 Telemeter network is driven by the primary data channels needed for gauging stage, controlling diversions, and measuring water temperature. However, it can also connect additional data streams for other environmental variables including contactless infrared water temperature, conductivity, turbidity, dissolved oxygen, pH, fish counts, spectrophotometric estimates of harmful algae abundance, soil moisture content, or other measurements that could help forecast the onset of impaired water quality conditions or project water demand. The PWA Mk1 Telemeter is also capable of gauging gravity diversions that don't have sufficient head to operate a flow totalizer (previously considered "ungaugable"). Subscribers to this service will receive highly automated and accurate annual statements of water diversion and use. The hardware and software will be open-source in accordance with the ISFP requirements.

HBNWR Long Pond

HBNWR Dashboard

(This telemeter is located just on the inside of a tide gate. You can observe dramatic changes in water levels and conductivity corresponding to the amount of ocean water that is being let in to the marsh.)

Time is in UTC.

Water Elevation:

Conductivity:

Temperature and humidity inside of enclosure: