Product category:
Water purification
News Release from: YSI Hydrodata | Subject: Hydrosam
Edited by the Laboratorytalk Editorial
Team on 20 April 2007
Intake protection make for better water
works
The heart of the Hydrosam is a multiparameter probe known as a sonde, thousands of which are in use all over the world as insitu water quality loggers in both freshwater and marine applications
Severn Trent Water was one of the first utility companies to try YSI's new multiparameter intake protection system, the Hydrosam, and works manager Natalie Horton says: "The performance of the new water quality monitor has been absolutely brilliant" Hydrosam is designed to replace older water quality monitoring systems that draw samples through a network of pipes which feed a series of in-line sensors
This article was originally published on Laboratorytalk on 16 May 2006 at 8.00am (UK)
Related stories
Water quality monitors are multiparameter
To accommodate twice as many optical sensors as well as provide mechanical improvements, YSI has released new versions of its multiparameter water quality instruments, called sondes
New optical sensors for blue-green algae
These two sensors use the in vivo fluorometry (IVF) technique, which measures the fluorescence of accessory pigments unique to blue-green algae (cyanobacteria): phycocyanin or phycoerythrin
Until now, these wall mounted systems have been installed to monitor water quality upstream of river abstraction points, so that plant managers are provided with data that can inform water treatment decisions.
However, such systems require a high level of maintenance and frequent calibration.
In contrast, the Hydrosam has been designed for minimum maintenance and long-term deployment.
Further reading
Optical DO sensors increase field accuracy
Luminescence-based dissolved oxygen sensor from YSI offers researchers and water quality technicians a powerful tool for long-term oxygen measurements in severe fouling and low-oxygen environments
YSI in deep water at WWEM 2006
YSI Hydrodata will run a workshop at WWEM on Wednesday 1 November 2006 at 12 noon entitled 'Monitoring the water column in a london reservoir to improve intake quality'
Undergraduate sterilisation
...would be one way to keep the student population under control, but this story has more to do with the production of sterile agar plates for bacteria cultures than the aftermath of Freshers Week
Water quality monitoring sondes are often left in remote and difficult to access locations and it is for this reason that YSI has, over many years, developed sensor technology that is able to take accurate readings without the need for frequent site visits.
The sondes have also been designed to be compact and this provided a further benefit to the Hydrosam; river water is pumped through a single sample chamber in which the sonde is located, so that all of the sensors are exposed to the same sample.
The Hydrosam employed by Severn Trent Water monitors pH, temperature, conductivity, turbidity, dissolved oxygen and ammonia.
However, it would be possible to add sensors for chlorophyll and blue/green algae.
The sequence of events that ended with the installation of the Hydrosam began with Horton becoming increasingly frustrated with the problems and high maintenance requirements associated with traditional monitoring systems.
However, she had heard that the Environment Agency deploy multiparameter sondes in rivers and approached YSI Hydrodata to discuss the possibility of their use for intake protection.
As a result, a sonde was installed directly in the river Severn upstream of the Shelton WTW near Shrewsbury on a three-month trial.
Prior to the trial, Horton admitted to a fair degree of scepticism over the sonde's ability to cope with occasional high levels of fouling.
However, after visiting the site, she said that she was: "Delighted to discover that, as a result of the inbuilt sensor wiping mechanisms, the sensors were completely free from fouling and the readings correlated very closely with our own calibrated equipment".
Following the success of the trial, Severn Trent Water ordered a full Hydrosam which has been permanently installed ten miles upstream of the water intake.
The system provides almost continuous monitoring data to the Shelton works and operators have been provided with the facility to dial in to the unit from anywhere or to visit the site and collect data with a portable computer.
Alarm conditions have been set and the unit will issue alarms via the PCMS should those conditions arise.
Horton has since become risk and safety manager for water supply at Severn Trent Water.
Looking back over the Hydrosam trial she says: "It is vitally important for our water treatment works to be provided with advance knowledge of water quality and trends so that we can manage the treatment process as effectively as possible.
"It is always our aim to maintain stability in the plant because unforeseen changes in the intake could necessitate a need for reduced flows to maintain water quality.
"For example, turbidity can range from 1NTU to over 200NTU, but this can be accommodated quite easily if we have an accurate and reliable intake protection system.
"However, the main benefit for us has been the reduced requirement for calibration and maintenance; site visits used to be necessary every week, but now a simple six-weekly calibration check is all that is needed.
"We have been delighted with the Hydrosam - it was simple to install and operate, it has proved to be reliable, and it saves labour costs.".
• YSI Hydrodata: contact details and other news
• Email this article to a colleague
• Register for the free Laboratorytalk email newsletter
• Laboratorytalk Home Page
Search the Pro-Talk network of sites
