SPiVolt is an innovative system provided by TerraDat for the near real-time detection and remote monitoring of leaks in embankment dams. Through continuous measurement of the Self Potential field, SPiVolt provides environmentally sensitive, low cost and accurate subsurface information.
TerraDat combines its comprehensive background in engineering geophysics with modern wireless technology to develop a word-class remote leakage monitoring system for the water industry. This is SPiVolt. Our service is backed by academic research and proven case studies with major companies.
SPiVolt data is displayed in near real-time via an interactive web portal accessible by logging into your account. We also provide ground deformation data delivered by SatSense Ltd to give a holistic understanding of the ongoing geophysical processes at your site.
We understand that all sites differ.
Any geophysical investigation or monitoring system is affected by the current condition of the subsurface (e.g. localised changes in physical properties of the engineered or natural materials beneath the suite, known or unknown structures/utilities and the geology that surrounds an embankment dam).
To optimise the position and interpretation of the SPiVolt monitoring data, TerraDat first carry out a site-wide geophysical investigation. This typically includes: electromagnetic ground conductivity, magnetometry and electrical resistivity tomography. A full interpretive report is then issued detailing the findings before the SPiVolt array design is finalised.
An array of passive electrical sensors is installed just below the surface of the area of interest. Sometimes the area of interest is obvious from surface expression of leakage.
The SPiVolt sensors measure variations in naturally occuring voltages within the ground called Self Potential. Changes in the amount and nature of groundwater flow are detected over time and relayed to our remote logger that in turn relays the data to our data centre.
Our customers are able to log into the portal to view the site data and configure alerts.
A full report is provided combining our interpretation of the subsurface structure, groundwater flow paths and the relation to rainfall / water levels.
SP surveys measure the naturally occurring electric potential (in volts) between an array of sensors and a reference sensor situated away from the area of interest. Several effects create the measurable potential, but it is significantly affected by water flow within soil pore space (known as streaming potential). SpiVolt was developed to answer the water industry's requirement for a reliable leakage monitoring system by combining a detailed understanding of the SP phenomenon with novel processing steps and modern telemetry.
The schematic diagram further illustrates this process. The SP technique is widely used in academia to study groundwater movement. The SPiVolt system transfers this academic success to a commercial market.