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22/03/2023 : OTT ecoLog 1000 Now with Conductivity Measuring Capabilities

OTT Hydromet has launched a new variant of the OTT ecoLog 1000, an all-in-one instrument with a water level sensor, logger, and cellular modem built in. The new variant is equipped with a rugged and accurate, 4-electrode conductivity measuring cell allowing the user to measure water level, temperature, and conductivity.

OTT HydroMet has a reputable track record of designing instrumentation for water level, conductivity, and water temperature all in one device, with examples like the OTT PLS-C, pressure level sensor with conductivity, OTT CTD, and OTT ecoLog 800. This technical expertise is incorporated into the design of the OTT ecoLog 1000. 

The ability to continuously measure conductivity gives insight into how varying environmental factors may be influencing water quality at monitoring sites. Water conductivity data can be used to identify the presence of dissolved minerals or ions, such as salt, in a system. With this knowledge, users can determine the potential uses of their water for drinking or irrigation and monitor overall aquifer health. 

Conductivity data is fundamental to the derived water quality parameters of Total Dissolved Solids (TDS) and salinity. With the new variant, awareness is gained surrounding events like saltwater intrusion, pollutants from surface water runoff, and other environmental impacts. 

All variants of the OTT ecoLog 1000 are simple to operate using a smart phone, tablet or PC through LinkComm operating software via integrated Bluetooth Low Energy (BLE) for local communication. LinkComm enables intuitive device set-up and configuration changes in the field and a simple step-by-step interface for calibrating the optional conductivity cell. The integrated cellular modem supports near real-time data visibility and remote station configuration changes to avoid unnecessary, expensive trips to measurement sites. 

“The new capability of the OTT ecoLog 1000 to measure conductivity opens a world of possibility for users looking to remotely monitor basic water quality parameters at select sites in their network. The compact design of the instrument with an integrated cell modem makes installation quick and maintenance minimal.” - Greg Koch, Global Product Manager, Hydrology. 

24/02/2023: OTT HydroMet Expands UK Team

OTT HydroMet, the developer and manufacturer of environmental monitoring solutions, has announced the appointment of Dr. Liam Goodes as Sales and Business Development Manager in the south of the UK.

Liam has an MSci in Oceanography from the University of Southampton and the University of Bordeaux, and a PhD in Marine Surface Engineering from the University of Southampton. He has since worked in optics and scientific hardware sales for a number of years, and in his spare time, he is a keen competitive archer.

Looking forward, Liam says: “Working closely with customers, the OTT HydroMet Group is constantly developing new technologies, and now offers a comprehensive package of solutions for environmental monitoring, communications and data management. I am therefore extremely excited to be appointed to this role, and look forward to helping customers gather the measurement insights they need.”

17/02/2023: Enhanced Connectivity for Remote Water Level Logger

OTT HydroMet has added additional communication options to its water level and temperature logger, the OTT ecoLog 1000. Now equipped with low-power LTE-M (CAT M1) connectivity, the device provides water professionals with simple, fast access to their water level data.

LTE-M is a type of low-power wide area network communication technology standard for a wide range of cellular devices and services in machine (M2M) and IoT applications, such as networks of groundwater monitoring sites. LTE-M has 5G compatibility making it future proof as cellular networks evolve. Mobile devices, smart phones, and tablets operating with Android, iOS or Windows 10 are all supported. In addition, simple local communication is available via Bluetooth.

By supporting 4G and cellular IoT transmission, LTE-M increases the speed and lowers the cost of data transmission, enabling users to conduct remote two-way operations such as configuration, network management, data download or the viewing of real-time data.

Robust, simple to install, and running on low-power with a 10-year battery life, the ecoLog 1000 has been designed specifically for long-term, unattended deployment. Enhanced connectivity further reduces the requirement for site visits, and lowers the cost of ownership.

Further information is available on the OTT Hydromet Blog.

12/05/2022: New Game-Changing Smart Water Level Sensor

OTT Hydromet has launched a new water level sensor, the OTT PLS 500, which combines robust reliability and accuracy with the advantages of smart sensor technology. Building on decades of experience, the redesigned PLS 500 retains key elements of the trusted, robust, and reliable OTT PLS, while enhancing the sensor to be intuitive and user friendly.

The OTT PLS 500 is a vented water level and temperature sensor with a stainless steel body and a robust ceramic pressure cell for improved accuracy and reliability. As a smart sensor it includes built-in QA/QC and metadata to verify sensor performance and validate data. This means that the sensor is ideal for extended deployment in remote locations.

“This new technology is all about long-term accuracy and reliability,” explains Greg Koch, Global Product Manager, OTT HydroMet. “The PLS 500 is fitted with a humidity sensor and an inclinometer to provide insight to mitigate condensation in the vented line and sensor movement or misalignment. The result is a smart sensor that continually checks itself to ensure that measurements are being taken correctly, with the ability to raise alarms if necessary.”

In addition to pressure (water level), the device also measures temperature to facilitate the automatic compensation of level measurements based on variation in water density.

An important feature of the PLS 500 will be a new capability to conduct data processing to improve the efficiency of data reporting and eliminate manual data post-processing/ analysis. For example, the probe will be able to automatically undertake internal calculations such as averages, minima and maxima, as well as discharge calculations from either a user-defined rating table or an ISO 1100-2 exponential formula set-up via SDI-12 commands.

Communication with the PLS 500 has also been enhanced, with the standard/simple communication protocols of SDI-12 or Modbus RTU (via RS-485).

Neatly summarizing the main advantages of the PLS 500, a Device Beta Tester with the State of Colorado Natural Resource Agency said: “The metadata and sensor flags are a game changer to ensure quality data remotely.”


OTT HydroMet Invests in High-Calibre Engineer

Responding to the continued growth in its UK business, OTT HydroMet has recruited a further field service engineer to its UK team. Simon Cockcroft joins from Siemens and will be responsible for helping with field installations, instrument service and calibration. “I have always wanted to work with the latest technologies, but in the field, and OTT’s installations are often exactly that,” Simon explains.

OTT HydroMet’s European Service Manager, Robin Guy says: “We are delighted to welcome Simon to the team. Our company’s longstanding reputation is built on the quality and reliability of the environmental data that our equipment delivers, so we need people of Simon’s calibre to ensure that we continue to deliver the highest possible levels of service.”

Simon has a first-class degree in Electronic Engineering from Newcastle University, in addition to an MSc in Mechatronics and Robotics from the University of Leeds. At OTT HydroMet, he will be responsible for installing and servicing the company’s range of environmental monitoring, communications and data management products.

Growth Prompts Need for New OTT HydroMet Service Technician

OTT HydroMet is a global developer and manufacturer of technologies to help detect floods, make solar power more efficient, protect the environment, and ultimately save lives. Following growth in the company’s UK business, OTT HydroMet is seeking a new service technician to add to the UK team.

OTT HydroMet’s Service Technicians are the custodians of the company’s long-standing customer relationships. The successful applicant will be responsible for supporting OTT’s Senior Field Service Technicians, both in the field and the workshop. This role has direct customer contact as well as high visibility and exposure to all departments in the organisation. The medium to long-term goal for this role will be to reach a comfort level to work independently in the field.

This position will be based at OTT’s Sheffield facility, with 70% - 80% travel to customer sites. Most travel will be local day trips, but some may require an overnight stay.

Applicants must have completed studies or technician training, preferably in the field of electrical engineering, information and communication technology, or hydrometry/ meteorology.

A competitive salary is available, along with the benefits of working for Danaher - a global organisation with over 80,000 employees.

To apply for this role, visit

Bridge scour risk lowered in Transport Scotland trial with OTT remote water level monitoring system

bridge scour water level monitoring system

Engineers at Transport Scotland have investigated the potential for water level monitoring systems to help mitigate risks where transport infrastructure interacts with moving water. The trial was conducted at a bridge over Vales Burn near Hawick in Scotland, and the monitoring equipment was provided by OTT HydroMet. OTT’s Wendy Strain says: “The system was set to deliver alarms at pre-set water levels, which enhanced the timing and efficiency of site inspections.”
Climate change is increasing the frequency and severity of extreme weather events such as storms and floods. This presents a growing threat to structures that could be susceptible to scour during periods of high water flow. The trial was therefore established to determine whether access to remote water level measurements could enhance the protection of critical transport infrastructure.


The stability and integrity of structures such as bridges, culverts and walls can be compromised by ‘bridge scour’ which is caused by fast-flowing water that removes material from around the footings of bridge abutments or piers.

There are three main types of scour. Local scour is caused by the faster water flow that occurs around piers and abutments. Constriction scour is created by water accelerating through a narrow opening, and degradation scour can lower a river bed over a longer period, both upstream and downstream of a structure.

The effects of bridge scour can be disastrous. For example, during a flood in 1987, the Glanrhyd Bridge in Carmarthenshire partially collapsed, causing a train to plunge into the River Towy, killing the driver and three of the passengers. In 2009, failure of the Malahide Viaduct in Dublin, Ireland was caused by foundation scour. Two commuter trains packed with hundreds of passengers were just seconds away from disaster when a 20-metre section of the viaduct collapsed after they passed over it. Nobody was killed, but travel chaos ensued.

Today, highways and rail authorities conduct regular inspections in order to asses scour risk.

Bridge scour in Scotland

Transport Scotland is split into four operational regions, and Jim Brown is South East Unit Bridge Manager. Prior to this position, Jim spent 42 years as a civil engineer with Network Rail, 13 years of which he headed the geotechnical discipline in Scotland – so it is fair to say that Jim knows a thing or two about bridge scour. “The most important objective is the early detection of increased risk,” Jim explains. “Once we have established which structures are more vulnerable during flooding, we are able to implement different levels of mitigation.

“Much research has been undertaken in an attempt to be able to monitor scour, but this is obviously problematic because potential scour takes place at times when it is not possible to see the river bed and certainly not possible to deploy divers,” Jim adds. “For this reason, the continuous monitoring of water level is not the perfect solution, but may be the best and most practicable.”

Water level is already used as a risk factor by the inspection teams where the 1 in 200 flood level is shown on structures by a fixed marker. However, Transport Scotland have to monitor 700 structures which are over or adjacent to water, and site inspections are costly; both financially and in resources. The inspection system could therefore be more efficient if it could be informed by remotely available water level data, especially if the data enables faster, more efficient implementation of mitigation measures.

If a structure is determined to be high risk, a hydrological assessment is undertaken. This may prompt a requirement for strengthening of the structure itself, as well as measures to protect or fill potential scour zones, and/or to alter water flow and disrupt vortices. In extreme cases, when a potentially vulnerable structure is exposed to high water, it may be necessary to close highways or rail lines until the level of risk can be lowered.

Vales Burn trial

In light of the potential for live water level data to inform the bridge inspection process, OTT HydroMet was invited to propose a monitoring system that could be evaluated at a culvert on the Vales Burn. “Our solution was comprised of an OTT ecoLog 1000 water level logger in a stilling well, with cellular data connection to Hydromet Cloud; a web-enabled platform for processing, displaying and storing hydrometeorological data,” explains Wendy Strain. “Data were set to be transmitted routinely every 6 hours, but two alarm levels were set to prompt SMS alerts, when necessary.”

The monitoring system was installed in September 2021, and Jim Brown says: “The trial is a great success; we utilise the Scottish Environmental Protection Agency (SEPA) flood alert warnings to monitor flooding and it has been our experience that the highest water levels generally occur about one or two days after a storm, so one of the main objectives of the trial was to determine the best time to despatch inspection staff.

“The monitors did issue alerts during the trial, but these were when levels met the lower alarm level, and in these cases, further interventions were not required. With the benefit of water level data, we will therefore be able to optimise the deployment of the inspection teams and mitigate risk,” Jim adds.


Bridge scour is a long-standing problem for transport infrastructure, so the deployment of remote water level monitors/alarms that can be accessed via PCs or a mobile App offers rail and highway authorities an opportunity to optimise their scour assessment activities, prioritise countermeasures, improve transport resilience and protect safety.

Reflecting on the trial Jim says: “This project has shown that a network of water level monitors could inform bridge engineers of potentially affected structures. I understand that the Hydromet Cloud platform is able to connect with an almost infinite number of water level monitors, so we may be able to roll this out on a larger scale in the future.”

24/11/2021: OTT HydroMet Invests in UK Growth

As the world is seeking new ways to fight climate change and develop mitigation strategies for severe weather, OTT HydroMet’s UK business has invested in two new positions to help meet that need. “Our technologies and data management solutions enable customers to monitor water resources and weather more effectively than ever before,” explains OTT HydroMet’s Robin Guy. “This means that we can play a role in not just monitoring the changing climate, but also helping to create severe weather warning systems that issue timely alerts to protect life and property. We have therefore recruited two new highly qualified and experienced business development managers that will offer customers the highest levels of support as they plan their monitoring and rapid response capability.”

Lewis Taylor will support old and new customers in the south of the UK, and Wendy Strain will cover the north.

Lewis has a first class degree in Mechanical & Manufacturing Engineering from the University of South Wales, and a Post Graduate Certificate in Professional Engineering from Cardiff University. He has worked as a CAPEX and OPEX process improvement engineer on several major water projects, and has 15 years of experience in sales and project management for major industrial water customers.

Wendy has a degree in Applied Chemistry from Liverpool John Moores University, and has 15 years of experience in municipal and industrial water and wastewater treatment, including 8 years in a consulting role; providing technical advice and training on mechanical and chemical water treatment.

“We are delighted to welcome these two talented individuals to our UK team,” adds Robin Guy. “The UK is already experiencing more frequent instances of severe weather, and COP26 has highlighted the fact that this situation is likely to worsen in the coming years. “We are therefore determined to help customers ensure that their monitoring networks are better able to detect issues such as intense rainfall, rising water, flooding and severe winds. These issues threaten lives and infrastructure such as highways, railways, buildings, industry and domestic housing, so Lewis and Wendy will be tasked with helping customers take advantage of the latest technologies in remote measurements, communications and data management software.”

20/08/2021: Meet OTT HydroMet’s Global Experts at Virtual WWEM 2021

OTT HydroMet will host a virtual exhibition booth at this year’s WWEM 2021 event; providing visitors with access to a world of expertise in sensors, dataloggers, telemetry and data management software for monitoring water and meteorology.

Taking place on 13th and 14th October, and with a clear focus on Water, Wastewater & Environmental Monitoring, WWEM 2021 will provide pre-registered visitors with free access to a range of conferences and workshops, as well as the opportunity to arrange appointments with experts from OTT HydroMet’s global locations.

“As a virtual event, WWEM will enable us to provide technical support from almost any location in the world,” explains OTT’s Application Development Manager for Europe Katja Weber. “However, given the variation in time zones, we are encouraging visitors to pre-arrange appointments with us; either via the exhibition portal ( or directly via our website

“At traditional exhibitions, most of the visitors are looking for help and advice such as: where to install monitors; which sensors to deploy; what service/calibration routine to choose; which loggers can handle remote operation; what telemetry method would be most cost-effective; how the system should be powered, and which data management platform to employ,” explains Katja.

“Experts from OTT HydroMet will be available to discuss all of these issues, as well as to demonstrate the latest technologies. There will also be a live feed to real-world water level data from one of our customer sites.”


07/07/2021: Big water data – more work? Or a great opportunity?

Water security can be defined as the availability of a sufficient quantity and quality of water to sustain livelihoods, health, socio-economic development and ecosystems. To achieve this goal, water managers need timely access to reliable, insightful, defensible data, but with the volume and speed of data now available, will existing data infrastructure be able to cope?

Recent developments in sensors, dataloggers and telemetry, have delivered intelligent monitoring systems that are able to operate remotely, running on very low levels of power and delivering reliable data in real-time. This has prompted dramatic growth in the implementation of high-intensity monitoring systems that generate enormous volumes of data. These systems also possess advanced alarm capability; issuing alert messages by SMS, email etc. when pre-set conditions arise.

Water management policies must be sustainable and resilient, so it is vital that both strategic and operational decisions are based on sound data. However, if data are not managed correctly, users may become ‘data-rich but information-poor’, so some of the most important decisions in the organisation of a monitoring programme relate to the ways in which data will be managed.

Working at every stage of the data collection process, OTT HydroMet has developed sensors that can operate remotely for extended periods; loggers that run on very low power but provide enormous data processing capability; telemetry solutions to transmit data from and to anywhere, and software that can assimilate vast quantities of data. The latest software (as a service) packages, such as Hydromet Cloud and AQUARIUS, are able to provide insights and alerts, while also providing easy access to live or historical data.

In combination, the OTT HydroMet solutions, from sensor to screen, enable water managers to meet the needs of disparate stakeholders and enhance water security. So, when it comes to the management of water, Big Data represents a fantastic opportunity.

For further information, please contact:
OTT Hydromet Ltd
Unit 19 Jessops Riverside
800 Brightside Lane
Sheffield  S9 2RX
Tel.  01246 573480
Fax. 01246 813873

23/07/2020: Satellite telemetry supports flood protection in Scotland

In recent years the development of flood warning systems has benefited from advances in sensor, datalogger and communications technology. The expansion of mobile telecommunications has meant that more locations now benefit from increased coverage, so that water level and meteorological monitoring systems can now be installed in remote locations. “In the past, data would have to be collected manually,” explains Robin Guy from OTT Hydromet. “However, this is both time consuming and costly, so modern systems employ telemetry to communicate with remote stations to lower costs and dramatically improve the speed and value of data."

“The most recent advance in remote communications has been the development of low-power, datalogging, satellite transmitters which are able to transmit sensor data from almost any location on earth. In the early days, satellite transmission of data was prohibitively expensive, but costs have lowered considerably; to the point where satellite telemetry competes directly with cellular communications.”

Scotland's water is famed worldwide, and performs vital roles both in tourism and in the production and branding of some of the country’s greatest exports. Water resources are monitored closely by the Scottish Environment Protection Agency (SEPA) to inform water management and to protect the environment; by detecting trends from climate change for example. Part of this monitoring activity is undertaken to provide a free advance flood warning service known as Floodline. This is a 24/7 telephone and website service providing advance notice of flooding, with advice on how to be prepared.

Floodline provides regional flood alerts which cover a wide geographic area and provide an early indication of potential flooding. This raises awareness and enables the public and emergency response services to prepare for possible flooding. Floodline also issues flood warnings for specific smaller areas where messages can be issued for local communities.

SEPA’s Flood forecasting and warning relies on a network of water level and precipitation monitors, some of which are located in remote areas of catchments, where the communications infrastructure can be less reliable. The SUTRON SatLink3, a combined datalogger and satellite transmitter, was therefore trialled at a site in Boat of Garten, near Aviemore. The logger is SDI12 compatible, and an OTT PLS sensor was used to monitor water levels and temperature, in addition to a raingauge and an air temperature sensor.

The SatLink3 is also Wi-Fi enabled which means that users are able to wirelessly set up and download the logger/transmitter with Android, iPhone or Windows devices. This also means that field staff can connect with the logger wirelessly from the comfort and safety of their vehicle – in any weather.

In the same way as a fee is payable for data transmission via mobile networks, many operators of satellite transmitters pay a small fee to transmit data via satellite. However, public organisations transmitting environmental data are able to use the EUMETSAT service free of charge.  This provides reliable and consistent one way transmission of data, and it is also possible to implement 2-way communications using the paid-for Iridium satellite service.

Following 2 months of successful operation in Aviemore, the monitoring and satellite communications equipment was transferred to a site near Aberfoyle to serve as part of a flood warning system for a period of 2 months. It was also deployed near Charr in Aberdeenshire at a primary flood warning station for a further 2 months because mobile communications at this location had been hindered by a new wind farm. After the success of the trials the latter 2 locations have since had agreement to install permanent SatLink3 dataloggers.

At each of the trial locations, data were transmitted every 15 minutes, and whilst 2-way communications were not available, the logger could be set to respond to certain conditions – to log at a faster rate for example. No maintenance issues occurred during the evaluation and as a result, around 20 new monitoring stations will be installed with satellite telemetry during 2020.

Commenting on the expansion of remote monitoring, Robin Guy says: “There are obvious cost advantages to be gained by collecting data remotely, but the effectiveness of flood prediction is greatly enhanced by the ability to gather timely data continuously from remote monitoring stations. This enables organisations such as SEPA to monitor at locations which are ideal for informing flood prediction models and warning systems.

“Advanced satellite telemetry is just one of the ways in which remote monitoring is enhanced; the latest sensors and loggers operate on very low power, with extended periods between service and calibration. Most sites can therefore operate from solar power and the necessity for site visits is dramatically reduced.

“The quality and reliability of cellular communications can vary in remote locations – often because the signal is reliant on a single mast. So, when a local mast has a problem or is out of service, the signal will be lost. Satellite telemetry has proved to be extremely reliable and is therefore becoming a useful tool in many locations; helping to improve the reliability and resilience of monitoring networks.”

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10/07/2020: Real-time access to Antarctic tide data

One of the most important challenges, when designing monitoring facilities in remote locations, is resilience. Remote tide gauge systems operate in extremely harsh environments and require robust communications systems that almost never fail and are capable of storing large amounts of data locally as an extra protection for data. Scientists from the National Oceanography Centre (NOC) are therefore upgrading the South Atlantic Tide Gauge Network (SATGN) to include the latest low power dataloggers with built-in satellite telemetry capability – the SatLink 3 from OTT Hydromet.

The SATGN is maintained and operated by the National Oceanography Centre, which is the UK centre of excellence for sea level monitoring, coastal flood forecasting and the analysis of sea levels. It is the focus for marine water level research in the UK and for the provision of advice for policy makers, planners and coastal engineers.

The SATGN measures sea levels in some of the most remote places on Earth. Monitoring sites include Antarctic locations such as Rothera and Vernadsky; located around 1,400 km below the southern tip of Argentina. Prior to the installation of this network there was a lack of information on sea level variations in the Southern Atlantic and a bias in tide gauge records towards the more densely populated Northern hemisphere. Over the last 30 years data from the SATGN have improved estimates of global sea level change, such as those reported by the Intergovernmental Panel on Climate Change.

The NOC at Liverpool operates and maintains the SATGN providing near real-time sea level data for operational purposes and scientific research. This has helped to provide a long-term sea level record that is used by UK scientists and the wider scientific community to monitor the Antarctic Circumpolar Current (ACC) variability. The data is also being used to help in the ‘ground truthing’ of satellite altimetry as well as the evaluation of climate variability on various timescales including longer term changes. In addition, the data is being used by local communities to provide essential information for both government and port authorities.

Monitoring/telemetry system upgrade

In recent years, the SATGN has undergone a refurbishment programme to reduce running costs and to safeguard local populations and infrastructure by providing tsunami monitoring capability and improving resilience. These new gauges couple Global Navigation Satellite System (GNSS) land level monitoring technology with tsunami capable radar and pressure sensors, transmitting data in near real-time by satellite based communications systems to operational monitoring centres.

As part of this NOC ongoing program, the tide gauges’ main datalogger and transmitter have been upgraded to incorporate OTT’s new Sutron SatLink3. The first site to receive this upgrade was the Vernadsky station located in Antarctica, which is now operated by Ukrainian scientists and is soon to be followed by the tide gauge at King Edward point, on the South Georgia islands.

A further advantage of the upgrade is the SatLink3’s ability to communicate via Wi-Fi with wireless devices, including smart phones, tablets and computers. This means that local staff can connect wirelessly to the logger from a few metres away, which is a major advantage during inclement weather conditions.


The SatLink3 datalogger is capable of accepting readings from a wide variety of sensors, with 2 independent SDI-12 channels, 5 analogue channels, one 4-20 mA channel and 2 digital inputs. The Vernadsky station includes a barometric pressure sensor, a radar level sensor installed over a heated/insulated stilling well (keeps the inner core free of ice) and two OTT PLS pressure level sensors which provide accurate measurements of water depth.

The network is using the Geostationary Operational Environmental Satellite (GOES) to transmit data. GOES is operated by the United States' National Oceanic and Atmospheric Administration (NOAA)'s National Environmental Satellite, Data, and Information Service. One minute averaged data is transmitted every 15 minutes. The data is then made freely available on the IOC Sea Level Station Monitoring Facility web site


By upgrading to the SatLink3 logger/transmitter, the NOC is enhancing the resilience of the South Atlantic Tide Gauge Network. Jeff Pugh from the Marine Physics and Ocean Climate Group at the NOC, says: “The data from this network informs models that assist with projections relating to climate change, and others which provide advance warnings that can help protect life and property. Given the remote locations of the monitoring sites, it is vitally important, therefore, that the instruments are extremely reliable, operating on low power, with very little requirement for service or spares. By transmitting almost live data via satellite, these monitoring systems enable the models to deliver timely warnings; advance notice of tsunami, for example, can be of critical importance.”

Satellite telemetry is becoming increasingly popular in many other parts of the world. “Some government and non-commercial organisations are able to utilise a variety of satellites free of charge,” explains OTT’s Nigel Grimsley. “However, the cost of transmitting data via satellite has reduced considerably recently, and now rivals the cost of cellular communications.”

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04/2020 OTT wins national water level sensors contract

Following a competitive tendering process, the Environment Agency has awarded OTT Hydrometry (UK) with a national contract to supply submersible pressure sensors to be used in water level measurement applications associated with surface water, groundwater and tidal water monitoring.

The contract is part of a joint procurement exercise with SEPA (Scottish Environment Protection Agency) and NRW (Natural Resources Wales).

The contract applies to Lot 6 of a telemetry and control equipment tender, which covers digital output ceramic diaphragm sensors with SDI:12 and Modbus output, for use where sensors require regular cleaning or where surrounding water is susceptible to freezing during the winter.

Under the contract, OTT will supply the OTT PLS sensors until November 2022, with options to extend for a further two periods of 12 months thereafter. The PLS is a robust ceramic pressure cell, providing long-term measurement stability. Resistant to physical force (5 x burst pressure) and with an enclosure made of high-quality saltwater resistant steel, the PLS is suited to a wide variety of freshwater and marine applications.

As a vented probe, the PLS maintains measurement accuracy by automatically compensating for changes in barometric pressure, and a built-in microcontroller compensates for temperature effects. The sensor also applies correction values for gravitational acceleration and water density. The sensor’s robust cable has a Kevlar core, and with flexible output formats, it can be connected to a wide variety of dataloggers and outstations.

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03/2020: OTT promotes natural flood management at Floodex

Visitors to the OTT Hydromet stand at the recent Floodex exhibition were provided with a free sapling, as part of the company’s efforts to promote tree planting as a way to capture carbon in the fight against climate change, and also as a natural flood management tool.

“As floods become more frequent and severe, many of our customers are starting to implement natural flood management (NFM) alongside more traditional engineering measures,” comments OTT MD Nigel Grimsley. “NFM seeks to ‘slow the flow’ – reducing peak flow, flow volumes and time to peak, especially in small catchments. As a manufacturer of precipitation, water level and flow monitoring equipment, we are intimately involved in measuring the success of such initiatives.”

Tree planting is just one of a number of NFM measures, but it can help in a number of ways. For example, rainfall is intercepted by the canopy of a tree and partly evaporates from the branch and leaf surfaces. Water falling onto soil under trees penetrates more quickly and more deeply than on open grassland, particularly where soils are compacted.

Trees naturally remove water from the soil leading to a significant reduction in pressure on drainage systems in urban areas and a reduction in flood risk in rural areas. In severe circumstances, trees can also provide a drag on flood water; acting as a porous barrier and thereby helping to slow the flow in upper regions of a catchment.

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02/2020: Building reliability into facility management sensors & systems

OTT Hydromet has launched a suite of high quality meteorological sensors that are ideal for the construction and building management sectors. “The latest Lufft sensors, the WS Series, deliver professional-grade weather data with instruments that are extremely compact, rugged and reliable,” says OTT UK Managing Director Nigel Grimsley. “In the past, customers would have had to purchase multiple sensors to monitor outdoor conditions effectively, but this can now be achieved with substantially less costly devices; many of which would easily fit in the palm of your hand.”

Weather monitors are routinely employed at construction sites to check that local conditions are suitable for work such as pouring concrete or operating cranes, but with facility managers looking for more sustainable solutions, Nigel says the largest market is now building management systems (BMS).

OTT Hydromet is a specialist manufacturer of smart weather instruments for environmental monitoring and building automation purposes. With no moving parts, OTT’s comprehensive range of compact, low-energy multiparameter sensors offer long-term reliability for almost any weather parameter with easy integration into building control, BMS and HVAC systems.

The WS range offers customers the ability to select from a range of parameters including temperature, relative humidity, air pressure, wind velocity, wind direction, precipitation amount / intensity / type, UV index, sun direction, brightness and twilight, and global radiation.

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For 25 years the OTT HydroMet Group has had a strong representation in France with their local subsidiary in Aix-en-Provence - reason enough to review the success story of the subsidiary.

During the 80’s and beginning of 90’s OTT HydroMet had worked with a dealer near Paris to better serve the market in France. As business there had increased, the German headquarter OTT GmbH decided to transform the office of the local partner into an OTT subsidiary for the French market in 1994. They started as a two-man team in an office in Puteaux with the former distributor Dominique Dodane as the general manager and Martin Stuempfle as sales engineer and customer service. Martin Stuempfle had been travelling all over France to develop the business for OTT. For the further support, the two managers hired a sales assistant and later two sales engineers.

End of 1999, Stéphanie Lokos replaced the sales assistant as internal sales manager. In 2000, Martin Stuempfle took over the general manager position, followed by François Laurent in 2006.

Then OTT France office moved from Paris area to Aix-en-Provence beginning of 2000 and continued its development, hiring an inside sales person, as well as a dedicated technician, so that the team grew to six people in 2002.

In 2003, OTT France moved into a more modern, close-by facility and added a Service Manager to the team in 2005 to strengthen the service department. By 2010, the staff had grown to nine members, with three in sales, three service, and three administrators. Its size has remained the same to this day, except for a few changes within the assignments of tasks, such as the new role of a sales engineer looking after the meteorological market.

Over the years, the inclusion of further companies into the OTT HydroMet Group had a positive impact on the growth of the site in France.

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Weather monitoring in extreme conditions

A VENTUS X ultrasonic wind sensor has been deployed by researchers at the Summit Station on the Greenland Ice Sheet in the Arctic, 10,000 feet above sea level, as part of a project investigating the role of aerosols in cloud formation. With integrated heaters and no moving parts, the wind sensor does not require recalibration – a vital feature of equipment in one of the most remote locations on Earth.

Aerosols are important in cloud formation because they act as condensation nuclei, providing seeding sites for water vapour condensation, and as ice nucleating particles which modulate the formation of ice in clouds.

The Greenland Ice Sheet is of critical importance to human society because of its role in global sea-level rise, and is of particular concern because it is melting at an increasing rate. An understanding of aerosol-cloud interactions is therefore extremely important; especially where clouds are comprised of both ice and supercooled liquid water, because this represents a major source of uncertainty in weather and climate models. Scientists from the University of Leeds School of Earth and Environment, and the National Centre for Atmospheric Science are therefore seeking to reduce this uncertainty with the use of advanced remote sensing technology, such as radar and lidar, in combination with satellite observations and a suite of other ground-based sensors (such as the VENTUS) and state-of-the-art numerical weather and climate models.

The project is seeking to determine the extent to which different aerosol properties cause significant changes in clouds, and to quantify the role aerosols may have on the melting of the Greenland Ice Sheet. In addition, this work is evaluating regional and global numerical weather and climate model performance against the project’s observations; to identify any deficiencies that lead to biases in cloud occurrence, cloud thickness, and phase partitioning.


Note to editors:

  • The National Centre for Atmospheric Science (NCAS) is a world leading research centre dedicated to the advancement of atmospheric science, funded by the Natural Environment Research Council (NERC). NCAS carries out research in air pollution, climate and high-impact weather, and long-term global changes in atmospheric composition and climate, and provides the UK community with state-of-the-art technologies for observing and modelling the atmosphere. Find out more at and @AtmosScience on Twitter.
  • The University of Leeds is one of the largest higher education institutions in the UK, with more than 38,000 students from more than 150 different countries, and a member of the Russell Group of research-intensive universities. The University plays a significant role in the Turing, Rosalind Franklin and Royce Institutes.
    We are a top ten university for research and impact power in the UK, according to the 2014 Research Excellence Framework, and are in the top 100 of the QS World University Rankings 2020. Additionally, the University was awarded a Gold rating by the Government’s Teaching Excellence Framework in 2017, recognising its ‘consistently outstanding’ teaching and learning provision. Twenty-six of our academics have been awarded National Teaching Fellowships – more than any other institution in England, Northern Ireland and Wales – reflecting the excellence of our teaching. 
    Over a third of our academics are involved in applied research or as consultants to industry, and over the last ten years, the University of Leeds has produced more than 100 ‘spin-out’ companies.

Storm chaser joins OTT Hydromet sales team

Brad Guay is no ordinary new recruit. With a degree in Meteorology from Penn State University, he has worked for the Colorado-based Center for Severe Weather Research on a tornado research project investigating ground level conditions inside tornados. Brad worked as part of a team which deployed meteorological instruments into the paths of tornadoes at close range.

More recently, Brad worked in the sales team at Risk Management Solutions in New York City. Financial institutions use RMS models to better understand catastrophic events such as earthquakes, hurricanes and floods.

Commenting on Brad’s appointment, OTT Hydromet Managing Director, Nigel Grimsley said: “We are delighted to welcome Brad to our team; with in-depth knowledge of risk management, he understands the importance of reliable monitoring data, so he is well placed to help our customers find solutions to their monitoring needs.”

12/2018 - New Nitrate monitor lowers costs

Responding to global demand for improved monitoring of nitrate in freshwater, OTT HydroMet has launched a new optical nitrate sensor, the OTT ecoN. “This is fantastic news for scientists, catchment managers, water companies, regulators and environmental consultants,” says Ronan O'Maitiu, Global Product Manager for the OTT ecoN. “In the past, customers have been caught between low-cost/limited-performance sensors and high-end technologies, for which purchase costs prevent large scale deployment. The OTT ecoN neatly fills that gap; as a continuous nitrate monitor, with minimal maintenance requirements, it can be left to monitor in remote locations, and an optional wiper makes it suitable for extended deployments.”

In addition to a low purchase cost, the ecoN also lowers the cost of ownership because it is factory calibrated for life. As an optical sensor, the ecoN provides high accuracy and low resolution without the drift and interferences of ion-selective electrodes, or the ongoing reagent and maintenance costs of wet-chemistry analyzers.

Summarising, Ronan says: “Nitrate is an extremely important contaminant of freshwater, and the ecoN has proven extremely accurate and reliable in the field, so it has been priced for extensive deployment, and we are very excited with the prospects for this technology.”

Read full Press Release

02/03/2021 Water velocity measurements – whatever the weather

The OTT SVR 100 non-contact surface water velocity radar sensor has been designed to overcome the challenges presented by monitoring water resources that can quickly change from languid flow to a raging torrent.

“If you need to monitor the velocity of a river, it is often better to do so from above, so that your sensor is not affected by high water or debris,” explains OTT MD Nigel Grimsley. “The OTT SVR 100 was therefore designed to be mounted at a fixed point on a bridge for example, away from potential flooding. However, uncertainties can also arise from vibration caused by wind or traffic, so the SVR also has integrated vibration and tilt sensors to ensure that these effects do not harm the quality of the monitoring data.”

The sensor is compact, simple to install, and with a power-down feature operates from a long lasting battery, that can be charged by a solar panel.

Velocity measurements and sensor status information from the vibration and tilt sensors are available via SDI-12, RS-232, RS-485, and Modbus protocol.

Summarising, Nigel says: “We have designed this sensor for long-lasting remote operation with almost no requirement for service or calibration. As the threat of flooding increases, the value of real-time data grows, but with the SVR 100 the cost of ownership is minimal.”

02/03/2021 Water managers demand better, faster data

2020 was an unusual year in many respects, but for OTT Hydromet, one of the more remarkable features of the year was an unprecedented level of orders for water level and flow monitoring equipment. Amid increasing pressure from climate change and urbanisation, OTT’s UK Managing Director Nigel Grimsley explains the growing demand for monitoring technology that enables more effective water management.

Looking back

In 1978 OTT launched the Allgomatic – a large desktop device for ‘data measurement, storage and transmission,’ – it wasn’t even called a datalogger. Prior to the Internet and mobile phones, OTT’s customers were monitoring water level in boreholes and stilling wells with dip tapes or sensors such as shaft encoders and compressed air bubblers connected to displays, dataloggers or chart recorders. Discharge calculations were based on stage measurements, possibly with a point and hook gauge, combined with manual measurements of velocity with a rotating element current meter. Raingauges were mostly operating with a collection vessel or with a tipping bucket mechanism; recording tips with a connected datalogger. Inevitably, this provided a retrospective view of water resources that was mainly useful for detecting trends and informing models.

Flood protection measures at this time were often designed to increase channel capacity and/or divert water away from sensitive areas. This may have involved engineered flood defence infrastructure with higher flood defences and straighter channels. Flood plains were increasingly used for agricultural, commercial or residential development, and the creation of ever-growing areas of impervious concrete and asphalt increased flood risk at a time when climate change was starting to increase the frequency and severity of severe weather.

Looking forward

Jump forward to today and flood management has changed dramatically - Natural Flood Management (NFM) is now regarded as a more effective and sustainable strategy. Flood risk is now addressed on a wider catchment scale so that upstream initiatives do not have negative effects further downstream. This catchment based approach has meant that water managers are increasingly looking for solutions that employ techniques which work with natural hydrological and morphological processes and features to manage flood waters. These NFM techniques include the restoration, enhancement and alteration of natural features such as flood plains. However, there are many other ways in which NFM can help to lower peak flow and decrease flood risk. Tree planting for example, intercepts rainfall and overland flow, increases water infiltration into soil, and provides important connective habitat for wildlife, as well as providing increased carbon storage.

Tomorrow’s technology

In addition to the provision of baseline data, monitoring systems are also necessary for measuring the effectiveness of mitigation measures and providing timely warnings when alarm conditions arise. In order to better understand catchments, groundwater and surface water levels should be correlated with upper catchment monitoring which includes the measurement of meteorological parameters.

The demand for high intensity monitoring is growing rapidly, as water managers demand lower levels of uncertainty in their monitoring data, and seek to exploit the advantages of networks of continuous monitors. The high volumes of orders that OTT received in 2020 featured many networkable sensors such as the OTT ecoLog 1000; a self-contained surface and groundwater level logger with two-way communication for smart phones and tablets. Remote sensors were also highly popular, including the OTT SVR 100 surface water velocity radar and the OTT RLS non-contact radar level sensor. The volume of dataloggers with satellite communications capability is also increasing as network managers seeks to exploit the benefits of reduced data transmission costs.

The demand for better monitoring is driving the development of OTT’s latest hydrometeorological technologies, which can be summarised in four categories:

  1. Accurate, reliable, low-power, smart sensors
  2. Flexible, intelligent, easy-to-use dataloggers
  3. Reliable, appropriate, cost-effective telemetry with multiple transmission options and redundancy capability
  4. Customisable, easy-to-use, insightful, web-enabled, data management software

With the benefit of insights from comprehensive real-time monitoring networks, collecting high intensity data from multiple points, water managers will be able to make better informed, defensible decisions.

11/2018 - OTT HydroMet launches the new XLink 100 and 500

The latest durable, reliable, flexible and cost-effective data logger/transmitter to deliver data you can trust.

OTT HydroMet, a global leader in hydrologic and meteorologic instrumentation and solutions, introduces the Sutron XLink family, the Xlink 100 and 500, for the gathering and transmitting of environmental data. XLink 100/500 combines easy to use, intuitive software offering versatility and programmability. This combination assists the user to gather, store, and access large amounts of data using either cellular or Iridium transmission. The XLink 100/500 seamlessly integrates most environmental sensors, including smart, digital, and analog, while supporting common measurement protocols and interfaces, including SDI-12.

“We are very excited about this product launch, it builds upon the success of its predecessor, the xLink-1 family, and on the horsepower, ease of use, modularity and flexibility of the Satlink3 family combined with over 100 years of building quality and durable products to offer best in class site controller at a very competitive price”, says OTT HydroMet Global Product Manager Sherif Ahmed.

Accurate Data Collection and Remote Access

The new XLink family is ideal for any hydrologist, meteorologist, researcher or scientist who needs to collect accurate time series measurements from ur-ban environmental or remote monitoring stations. The remote capability via cellular or Iridium satellites allows users to access data from anywhere at any time. Remote two-way communication further saves valuable time with the capability to modify the logger’s configuration or turn on or off instruments. Similarly, the XLink 100/500 ‘s Wi-Fi capability allows quick setup and access to data stored on the logger from a smartphone or tablet. Its quick adaptability from one communication method to the next is due to its plug and go mo-dem, which requires only a quick switch of modules. This ensures that the logger can easily adapt to new developments in telecom technologies.

Simple, Easy to Use and Customizable

The operating software for the XLink, LinkComm, offers a wide variety of sen-sor templates, with wiring assistance and no additional programming required to use, but can also be adapted beyond the standard configuration to meet more complicated requirements. Python scripts can be easily used to make measurements and transmissions beyond standard configuration or to com-municate with external modems, displays and much more.

Increased Security and Data Collection Capacity

The XLink 100/500 is capable of measuring 32 environmental parameters simultaneously, enabling more complex configurations on site using just one logger. In addition, the new logger has the capability of storing up to 1 million readings. In the event of communication interruption, data loss risk is reduced as the data can be logged and stored on the device until it can be retrieved by a technician. Data security is at the heart of the design, with three access control levels to protect setup, maintenance and data from unwanted access. In addition, data can be encrypted using IP protocols, such HTTPS or FTPS, or password protected during transmission to the server.

Read full Press Release

11/2017 - Hydromet Launches new HYDROLAB HL7 Water Quality Sonde

Kempten, November 2017- OTT Hydromet, a global leader in providing hydrologic and meterologic instrumentation and solutions, introduces the HYDROLAB HL7 multiparameter sonde for continuous monitoring of 9 key water quality parameters in open natural waters. HYDROLAB HL7 includes intuitive software for unmatched usability, exceptional power performance and proven sensor options, all delivering high data quality and reliability.

HYDROLAB water quality instruments and software help environmental scientists monitor  the increasingly important changes in our water resources even in the harshest conditions. The sonde, when utilized with the central cleaning brush is ideal for long term deployments prone to bio-fouling such as in lakes, rivers, wetlands and estuaries.
“The HYDROLAB HL7 represents a smarter and more sophisticated water quality sonde”, said Ronan O'Maitiu, OTT Hydromet’s Water Quality Product Manager. “Matching a strong sensor heritage with intensive development and testing produced massive gains in deployment options and great functionality all streamlined into intuitive software.”   


10/2019: New water level monitor is mobile-friendly

OTT HydroMet has launched a new all-in-one wireless water level logger that can be used for the remote monitoring of surface or groundwater. Simple to set up and run with a mobile phone, the OTT ecoLog 1000 has been designed for long-term applications, even in remote locations, and is able to issue warnings automatically to help manage or avoid the problematic conditions that can occur when water levels rise.

“Our customers are already walking around with an incredible piece of technology in their pockets,” comments OTT’s UK managing director Nigel Grimsley. “So it makes sense to exploit the value of this by developing an App that can be used to set up, manage and view data, and by designing a water level monitor that communicates wirelessly with a mobile phone or tablet.”

The App runs on mobile devices supporting iOS, Android, Mac, and Windows 10, and with integrated Bluetooth Low Energy (BLE) communication, the ecoLog 1000 can pair with a mobile device up to 10 metres away, which significantly enhances simplicity and onsite safety. Further enhancements to onsite operations include the ability to quickly change batteries, and even shorten cable lengths if necessary.

An on-board SIM card enables the monitor to feed data to secure servers, and users are provided with password protected access to the readings via the App. However, in addition to viewing and downloading data, the App also enables users to manage the ecoLog’s configuration remotely.

For monitoring network operators, a further App-based solution, HydroMet Cloud, offers web-based data visualisation of live monitoring data in user-defined maps, graphs, tables etc.

With a rugged stainless steel probe (also suitable for brackish and saline water) and a very stable ceramic pressure cell, the ecoLog 1000 is designed for challenging applications. Data are encrypted with automatic retries if transmission fails, so users can expect continuous data streams with alerts when water approaches user-set threshold levels.

Commenting on the applications for the instrument, Nigel says: “A wide range of people would benefit from remote water level data and alerts; these include government agencies, flood managers, local communities, highway managers, rail network operators, water companies and water resource managers, as well as consultants, academics and environmental researchers.

“For all of these groups, easy access to remote data will save a great deal of time and money by preventing unnecessary site visits, and the provision of water level alarms will facilitate the instigation of timely mitigation measures.”

News July 2018

07/2018 - High frequency monitoring needed to protect UK rivers!

The science behind nutrient pollution in rivers is still poorly understood despite the fact that nitrate and phosphate concentrations in the UK’s rivers are mostly unacceptable, although an element of uncertainty exists about what an acceptable level actually is. Key to improving our understanding of the sources and impacts of nutrient pollution is high-resolution monitoring across a broad spectrum of river types. In the following article, Nigel Grimsley from OTT Hydrometry will describe relatively new technologies that have overcome traditional barriers to the continuous monitoring of phosphate and nitrate.

Phosphates and nitrates occur naturally in the environment, and are essential nutrients that support the growth of aquatic organisms. However, water resources are under constant pressure from both point and diffuse sources of nutrients. Under certain conditions, such as warm, sunny weather and slow moving water, elevated nutrient concentrations can promote the growth of nuisance phytoplankton causing algal blooms (eutrophication). These blooms can dramatically affect aquatic ecology in a number of ways. High densities of algal biomass within the water column, or, in extreme cases, blankets of algae on the water surface, prevent light from reaching submerged plants. Also, some algae, and the bacteria that feed on decaying algae, produce toxins. In combination, these two effects can lower dissolved oxygen levels and potentially kill fish and other organisms. In consequence, aquatic ecology is damaged and the water becomes unsuitable for human recreation and more expensive to treat for drinking purposes.

In its State of the Environment report, February 2018, the Environment Agency said: “Unacceptable levels of phosphorus in over half of English rivers, usually due to sewage effluent and pollution from farm land, chokes wildlife as algal blooms use up their oxygen. Groundwater quality is currently deteriorating. This vital source of drinking water is often heavily polluted with nitrates, mainly from agriculture.”

Good ecological status
The EU Water Framework Directive (WFD) requires the UK to achieve ‘good status’ of all water bodies (including rivers, streams, lakes, estuaries, coastal waters and groundwater) by 2015. However, only 36% of water bodies were classified as ‘good’ or better in 2012. In the UK, nutrient water quality standards are set by DEFRA, so for example, phosphorus water quality standards have been set, and vary according to the alkalinity and height above mean sea level of the river. Interestingly, the standards were initially set in 2009, but in 75% of rivers with clear ecological impacts of nutrient enrichment, the existing standards produced phosphorus classifications of good or even high status, so the phosphorus standards were lowered.

Highlighting the need for better understanding of the relationships between nutrients and ecological status, Dr Mike Bowes from the Centre for Ecology & Hydrology has published research, with others, in which the effects of varying soluble reactive phosphate (SRP) concentrations on periphyton growth rate (mixture of algae and microbes that typically cover submerged surfaces) were determined in 9 different rivers from around the UK. In all of these experiments, significantly increasing SRP concentrations in the river water for sustained periods (usually c. 9 days) did not increase periphyton growth rate or biomass. This indicates that in most UK rivers, phosphorus concentrations are in excess, and therefore the process of eutrophication (typified by excessive algal blooms and loss of macrophytes – aquatic plants) is not necessarily caused by intermittent increases in SRP.

Clearly, more research is necessary to more fully understand the effects of nutrient enrichment, and the causes of algal blooms.

Upstream challenge
Headwater streams represent more than 70% of the streams and rivers in Britain, however, because of their number, location and the lack of regulatory requirement for continuous monitoring, headwater streams are rarely monitored for nutrient status. Traditional monitoring of upland streams has relied on either manual sampling or the collection of samples from automatic samplers. Nevertheless, research has shown that upland streams are less impaired by nutrient pollution than lowland rivers, but because of their size and limited dilution capacity they are more susceptible to nutrient impairment.

Monitoring technology
Sampling for laboratory analysis can be a costly and time-consuming activity, particularly at upland streams in remote locations with difficult access. In addition, spot sampling reveals nutrient levels at a specific moment in time, and therefore risks missing concentration spikes. Continuous monitoring is therefore generally preferred, but in the past this has been difficult to achieve with the technology available because of its requirement for frequent re-calibration and mains power.

High resolution SRP monitoring has been made possible in almost any location with the launch by OTT Hydromet of the the ‘HydroCycle PO4’ which is a battery-powered wet chemistry analyser for the continuous analysis of SRP. Typically, the HydroCycle PO4 is deployed into the river for monitoring purposes, but recent work by the Environment Agency has deployed it in a flow-through chamber for measuring extracted water.

The HydroCycle PO4 methodology is based on US EPA standard methods, employing pre-mixed, colour coded cartridges for simple reagent replacement in the field. Weighing less than 8kg fully loaded with reagents, it is quick and easy to deploy, even in remote locations. The instrument has an internal data logger with 1 GB capacity, and in combination with telemetry, it provides operators with near real-time access to monitoring data for SRP.

The quality of the instrument’s data is underpinned by QA/QC processing in conjunction with an on-board NIST standard, delivering scientifically defensible results. Engineered to take measurements at high oxygen saturation, and with a large surface area filter for enhanced performance during sediment events, the instrument employs advanced fluidics, that are resistant to the bubbles that can plague wet chemistry sensors.

Environment Agency application
The National Laboratory Service Instrumentation team (NLSI) provides support to all high resolution water quality monitoring activities undertaken across the Agency, underpinning the EA’s statutory responsibilities such as the WFD, the Urban Waste Water Directive and Statutory Surface Water Monitoring Programmes. It also makes a significant contribution to partnership projects such as Demonstration Test Catchments and Catchments Sensitive Farming. Technical Lead Matt Loewenthal says: “We provide the Agency and commercial clients with monitoring systems and associated equipment to meet their precise needs. This includes, of course, nutrient monitoring, which is a major interest for everyone involved with water resources.”

Matt’s team has developed water quality monitoring systems that deliver high resolution remote monitoring with equipment that is quick and easy to deploy. There are two main options. The ‘green box’ is a fully instrumented cabinet that can be installed adjacent to a water resource, drawing water and passing it to a flow-through container with sensors for parameters such as Temperature Dissolved Oxygen, Ammonium, Turbidity, Conductivity pH and Chlorophyll a. Each system is fitted with telemetry so that real-time data is made instantly available to users on the cloud.

Conscious of the need to better understand the role of P in rivers, Matt’s team has integrated a HydroCycle PO4 into its monitoring systems as a development project.
Matt says: “It’s currently the only system that can be integrated with all of our remote monitoring systems.  Because it’s portable, and runs on 12 volts, it has been relatively easy to integrate into our modular monitoring and telemetry systems.

“The HydroCycle PO4 measures SRP so if we need to monitor other forms of P, we will use an auto sampler or deploy a mains-powered monitor. However, monitoring SRP is important because this is the form of P that is most readily available to algae and plants.”

Explaining the advantages of high resolution P monitoring, Matt refers to a deployment on the River Dore. “The data shows background levels of 300 µg P/l, rising to 600 µg P/l following heavy rain, indicating high levels of P in run-off.

Similar to phosphates, excessive nitrate levels can have a significant impact on water quality. In addition, nitrates are highly mobile and can contaminate groundwater, with serious consequences for wells and drinking water treatment. Nitrate concentrations are therefore of major interest to the EA, but traditional monitoring technology has proved inadequate for long-term monitoring because of a frequent recalibration requirement. To address this need, which exists globally, OTT Hydromet developed the SUNA V2, which  is an optical nitrate sensor, providing high levels of accuracy and precision in both freshwater and seawater.

The NLSI has evaluated the SUNA V2 in well water and Matt says: “It performed well – we took grab samples for laboratory analysis and the SUNA data matched the lab data perfectly. We are therefore excited about the opportunity this presents to measure nitrate continuously, because this will inform our understanding of nitrate pollution and its sources, as well as the relationship between groundwater and surface water.”

The new capability for high-resolution monitoring of nutrients such as phosphorus will enable improved understanding of its effects on ecological status, and in turn will inform decisions on what acceptable P concentrations will be for individual rivers. This is vitally important because the cost of removing P from wastewater can be high, so the requirements and discharge limits that are placed on industrial and wastewater companies need to be science based and supported by reliable data. Similarly, nitrate pollution from fertilizer runoff, industrial activities and wastewater discharge, has been difficult to monitor effectively in the past because of the technology limitations. So, as improved monitoring equipment is developed, it will be possible to better understand the sources and effects, and thereby implement effective prevention and mitigation strategies.

News Nov 2017

11/2017 - Hydromet Launches new HYDROLAB HL7 Water Quality Sonde

Kempten, November 2017- OTT Hydromet, a global leader in providing hydrologic and meterologic instrumentation and solutions, introduces the HYDROLAB HL7 multiparameter sonde for continuous monitoring of 9 key water quality parameters in open natural waters. HYDROLAB HL7 includes intuitive software for unmatched usability, exceptional power performance and proven sensor options, all delivering high data quality and reliability.

HYDROLAB water quality instruments and software help environmental scientists monitor  the increasingly important changes in our water resources even in the harshest conditions. The sonde, when utilized with the central cleaning brush is ideal for long term deployments prone to bio-fouling such as in lakes, rivers, wetlands and estuaries.
“The HYDROLAB HL7 represents a smarter and more sophisticated water quality sonde”, said Ronan O'Maitiu, OTT Hydromet’s Water Quality Product Manager. “Matching a strong sensor heritage with intensive development and testing produced massive gains in deployment options and great functionality all streamlined into intuitive software.”   


News June 2017

OTT issues Flood Warning

Nigel Grimsley, Managing Director of OTT Hydrometry (UK) is urging those responsible for flood prevention and management to take action this summer to ensure they are protected before the arrival of severe weather. “Saturated soil and blocked channels contribute to the severity of flooding, but in many cases it is the location and intensity of rainfall that contributes to the speed with which flooding occurs. Early warning of intense rainfall events or blocked channels is therefore essential. Recent advances in technology mean that it is now relatively simple and low cost to set up advanced warning systems so that appropriate measures can be taken quickly and effectively,” he says.

“The early implementation of prevention and mitigation measures provides essential protection for valuable assets. For example, on a small scale, we have installed water level monitors in village streams that are prone to flooding during intense rain or when channels become blocked. On a larger scale, we have supplied 153 monitoring stations for the Harris County Flood Warning System in Texas, where flooding represents a major threat to life and property, so early warning of intense rainfall and rising water levels provide opportunities for mitigation and where necessary, evacuation.”

OTT’s latest flood warning systems provide easy access to monitoring data from PCs and smartphones. However, crucially, they are also able to automatically issue text or email alarms when rainfall or water levels approach dangerous levels, so that timely action can be taken.

For more information, visit


News April 2017

OTT launches feature-packed ‘Hydromet Cloud’

The OTT Hydromet Group has launched a new web-based data management service for remote monitoring stations. “Hydromet Cloud represents a step-change in data management,” comments UK Managing Director Nigel Grimsley. “Subscribers to this new service are provided with fast, simple access to both live and historical data, which opens new opportunities for exploiting the value of ‘Big Data’.”

Packed with new features and highly cost-effective, Hydromet Cloud provides users with easy access to secure data from field monitoring sites at any time and from almost anywhere via or the Hydromet Cloud mobile App. Typical applications include hydrology, meteorology and water quality.

Data are transmitted from field stations through a variety of methods including satellite, cellular (GPRS/3G/4G) or wired internet connection, and stored/backed-up in the cloud.

Designed for flexibility, Hydromet Cloud enables users to create their own dashboard to quickly collate frequently viewed data, which can be displayed as plots, tables or values, and exported in a variety of formats, which enables easy analysis of trends. This facility to create a bespoke display is enhanced by a map view with colour-coded map pins (for alarm status), current data values and colour-coded parameter values highlighting alarm status. Alarms are user-defined for values, rate of change etc. and alarm messages are issued automatically by email, text or push notification on a mobile phone. Separate limits can be set for both warning and critical levels, and users can also create alarm distribution groups for notifications.

The Hydromet Cloud mobile App provides a quick and easy opportunity to view the status of an entire network or an individual monitoring station, with options to send/share data directly from a smartphone or tablet (iOS or Android). It is also possible to create and save ‘My Plots’ to quickly recall common plots of one or more parameters graphically illustrating recent data.

Hydromet Cloud provides secure infrastructure to receive, decode, process, display, and store measurement data from nearly any remote monitoring station via a cloud-based data hosting platform. Alternatively, for those wishing to conduct their own data processing, Hydromet Cloud delivers raw data (as it is transmitted by the station) using a dedicated download page, which is updated as soon as the data arrives. The system is fully compatible with the latest OTT and Sutron data logger/communication devices, in addition to a wide variety of OTT, Sutron, and Hydrolab sensors for water quantity and quality measurements, as well as Lufft meteorological sensors, third-party sensors and IP cameras.

Summarising, Nigel says: “We are very excited about the opportunities that Hydromet Cloud will create for our customers. This is the first major new product development since the acquisition of Sutron Corporation and is a great example of the synergy that has been created by merging the companies’ development teams.

“Our customers know that data serves two purposes: one, to enable the analysis of background trends, and two to quickly and easily facilitate management by exception when alarm conditions arise. Hydromet Cloud achieves both.”



News March 2017

‘Smart’ flood alleviation system protects Portsmouth

In late 2014, Southern Water completed a major project to reduce the risk of sewer flooding in parts of Portsmouth and Southsea. Substantial works were undertaken to divert runoff and tidal ingress, and a ‘smart’ hydrometeorological monitoring system was installed to enable prompt diversion of excess water during periods of high rainfall. Sewer level monitoring is undertaken in real-time and intelligent raingauges (smart sensors) combine with radio telemetry to inform a computer based catchment-wide water model. This decision support system provides advance notice for staff at the Eastney pumping station that diverts large quantities of water to storage tanks during periods of heavy rain. Through the development of a smart sewer network, Southern Water has dramatically reduced the risk of flooding in Portsmouth whilst also delivering substantial environmental benefits.

Portsmouth was one of the first cities in the UK to benefit from a dedicated sewerage system in 1865. At that time, the system combined foul and surface water systems, and was adequate because with less paved areas the flows were lower, and because flows were discharged into the sea untreated. Since that time, the City of Portsmouth’s drainage network has continued to develop but has remained dependent on the use of combined sewers and the Eastney Pumping Station. The city is now served by two interceptor sewers that run north to south on the western and eastern sides of the island. These interceptor sewers carry the combined sewage flows to Eastney. In dry weather, flows arriving at Eastney are screened and pumped to Budds Farm WwTW for treatment. These flows, together with treated flows from the Havant catchment, then gravitate back to Eastney and are pumped down the long sea outfall.

Historically, during periods of high rainfall, the incoming flows exceeded the capacity of the system and excess flow was pumped from the Eastney pump station to storm tanks at Fort Cumberland. These tanks have a capacity of 40,000m3 and are filled before any flows are discharged to the sea via the short sea outfall, and then emptied back to Eastney after the storm has passed. However, due to the quantity of storm water arriving at Eastney prior to the flood alleviation project, and allowing for filling and emptying the tanks, in a typical year 650,000m3 of screened wastewater was discharged via the outfall at Fort Cumberland, in the South East of Portsmouth at the mouth of the Langstone Harbour.

Approximately 60% of the catchment consists of built up areas, 80% of which drain to the Eastney pump station. This means that nearly half of the entire surface area of Portsmouth drains to Eastney, which causes extremely large flows during storm conditions. In dry weather, flows are less than 1,000 l/s. However, in storm conditions flows increase to more than 20,000 l/s.

On 15 September 2000 an exceptionally severe storm overwhelmed the Eastney pump station, causing the pump room to be flooded, which stopped the pumps and over 750 properties were flooded. Considerable investment has subsequently taken place at Eastney with the provision of a new standby pump station. However, with half of all rain that falls on the island ending up at Eastney there is still a major risk that the capacity of the pump station will be exceeded.

Portsmouth Flood Alleviations
SchemeThe majority of the flow in wet weather is surface water, so the Portsmouth Flood Alleviations Scheme was created to divert surface water to the sea instead of entering the combined sewer. This would free up capacity in the existing infrastructure, allowing it to be used to provide protection against larger storms. In total, surface flow from 34 Hectares of paved area was diverted by the project.

The flow reduction initiatives have reduced the flow arriving at Eastney to the extent that the required flood risk protection level has been achieved. In order to reduce tidal infiltration and tidal restriction of CSO operation, new surface water pipes, culverts and swales were created, and several sections of the public sewer were remediated.

Pump management
The large diesel pumps at Eastney have an enormous capacity, with a combined ability to remove 6,500 litres per second. However, they take 15 to 30 minutes to build up to full speed so advance notice is necessary. The pump station is manned 24 hours/day and a The pump station is manned 24 hours/day and a network of 10 sewer water level sensors, 4 pump monitoring systems and 4 rainfall monitors delivers data via OTT Adcon radio telemetry to a catchment software model developed by Innovyze.

Employing the latest technology, OTT Pluvio² raingauges are able to measure both rainfall amount and rainfall intensity. This is important because traditional raingauges simply supply historical data on the amount of precipitation, whereas near real-time access to precipitation intensity dramatically increases the speed with which the monitoring system is able to deliver storm warnings. Another key feature of these smart raingauges is their ability to operate reliably without the level of maintenance that is required by traditional raingauges. For example, they are able to issue alerts when maintenance is necessary.

Summarising, Rob McTaggart, technical lead at MWH says: “Collaboration with the community, and other stakeholders in Portsmouth, made it possible for the project consortium to design and implement a solution that separated surface water to provide resilience, significantly boost flood protection and benefit the environment with the minimum of new infrastructure.

“Clearly, the flood alleviation scheme has been a success and as a result, the pumps at Eastney are called into action less often.

“The early warning system appears to be working very well. Some of the rainfall prediction data, provided by external sources, can sometimes provide erroneous projections because of the localised nature of precipitation events, so it is important to have a sufficient number of raingauges to ‘calibrate’ projections and deliver the level of precision required.”



News Nov 2016

OTT showed Smart sensors at WWEM 2016

The OTT stand (No. 126) at WWEM 2016 provided the first opportunity for visitors to see the HydroCycle PO4, the latest version of the Cycle-P remote, battery powered, dissolved phosphate monitor. Designed for long-term high frequency monitoring of remote locations, the HydroCycle PO4 can be left unattended for long periods, testing up to 1,500 samples between service/reagent change. Onboard calibration with QA/QC processing and an internal datalogger ensure the reliable collection of accurate data, and telemetry options provide data access without frequent site visits.

 The latest version of the advanced Pluvio2 weighing raingauge was also on show, offering access to precipitation intensity data as well as total rainfall measurements. The real-time nature of the Pluvio2 measurements are making this a popular choice with regulatory authorities and those responsible for flood management.

 Following recent company acquisitions by the OTT Hydromet Group, new products from Sutron and Lufft attracted significant visitors attention.

 OTT also ran two Workshops on ‘Phosphate monitoring’ and ‘Low-maintenance real-time precipitation monitoring.’ Both of these addressed highly topical issues and were popular with visitors and the media.



News July 2016

OTT Hydromet partners with sister company Sea-Bird

The OTT Hydromet Group has announced a new distribution strategy for the Sea-Bird Coastal product range of water quality sensors and monitors. “These instruments fit very well with our range of water monitoring technologies,” says OTT’s European Sales Manager Marcus Meckelmann. “We also share similar customer bases, so the key Sea-Bird Coastal products will be available exclusively through OTT’s European subsidiaries and official distributors.”

The Sea-Bird products covered by this arrangement include the HydroCycle PO4 (formerly Cycle-P) phosphate analyser, the SUNA V2 nitrate sensor, the LOBO turn-key water quality monitoring system, the WQM and WQM-X water quality meters, the HydroCAT long-term deployment water quality sondes and the Hydro-pH deep water (350m) pH sensor.

In addition to the Sea-Bird products, the OTT Hydromet Group also includes leading global brands such as Adcon Telemetry, Hydrolab, Lufft, OTT and Sutron. “Our main focus is the provision of leading-edge, accurate, reliable instrumentation and telemetry systems that deliver vital data for those responsible for monitoring and managing water resources and the impacts of weather,” adds Marcus Meckelmann. “Nutrients represent a major threat to global water resources, so we are particularly excited by the opportunities presented by Sea-Bird’s low power nitrate and phosphate monitoring technologies.”

Sea-Bird’s ocean research products are also available through the OTT Hydromet distribution channels, but on a non-exclusive basis.

News June 2016

OTT launches new low-maintenance Phosphate monitor

OTT Hydrometry has launched an advanced version of its ‘Cycle-P’ remote Phosphate monitor for measuring dissolved Phosphate in rivers, lakes and reservoirs. The new ‘HydroCycle PO4’ uses less reagents per test than its predecessor and the reagents have a longer shelf-life. “This means that the HydroCycle PO4 can be left in the field, for even longer periods,” says OTT’s UK Managing Director Nigel Grimsley. “With a standard sampling rate of two tests per hour (4x per hour is possible), this new instrument is able to run over 1,500 samples before a service/reagent change is necessary, so that means the monitor can be left unattended for around a month, which reduces the cost of monitoring even further.”

Battery powered and weighing less than 8Kg fully loaded with reagents, the HydroCycle PO4 is quick and easy to deploy, even in remote locations. The instrument has an internal datalogger with 1 GB capacity, and in combination with telemetry, it provides operators with near real-time access to monitoring data for Phosphate; a critically important nutrient in surface waters.

The quality of the instrument’s data is underpinned by QA/QC processing in conjunction with an on-board NIST standard, delivering scientifically defensible results, and enabling users to spend less time checking data quality and more time analysing what the data means. The HydroCycle PO4 methodology is based on US EPA standard methods, employing pre-mixed, colour coded cartridges for simple reagent replacement in the field.

Engineered to take measurements at high oxygen saturation, and with a large surface area filter for enhanced performance during sediment events, the instrument employs advanced fluidics, that are resistant to the bubbles that can plague wet chemical sensors.

Summarising, Nigel Grimsley says: “The original Cycle-P significantly lowered the cost and improved the reliability of Phosphate monitoring, and the new version builds on the strengths of its predecessor and reduces the service and maintenance requirements even further.”


Intelligent monitoring system provides flood warnings

Water level sensing technology from OTT Hydrometry is being used in an intelligent flood warning system that has been installed at a ford in Kenilworth, Warwickshire, UK.  The system, which was designed and installed by SWARCO Traffic, monitors water level in the Finham Brook where it passes under the A452, and warns drivers when potentially dangerous conditions arise.

Working closely with Warwickshire County Council (WCC), SWARCO provided a set of four signs on the approach and in close proximity to the ford. The two signs that are closest to the ford initially warn of water on the carriageway (up to 100mm); these alert drivers to the flood and the risk of aquaplaning. When the water rises above 100mm the two outer signs are activated to enable drivers to take an alternative route, and the inner signs provide an additional message that the ford is impassable.

David Matthewson, team leader of the Traffic Control and Information Systems team at WCC, says: “This ford can be the cause of significant traffic problems during flood conditions; partly because drivers are unsure whether the road is passable and also because smaller cars can get into trouble when a passing larger car causes a wave.

“The two trigger levels were based on potential risk to motorists and although these can be adjusted locally onsite, we initially erred on the side of caution at commissioning. Following three periods of flood since late December 2015 we have slightly adjusted the trigger levels to reflect the depth of water on the carriageway during a flood."

The water level sensor is an OTT PLS (Pressure Level Sensor) located in a slotted stilling well. Designed for field applications, the robust PLS has a stainless steel housing, an integrated controller and a ceramic pressure-measuring cell. The sensor has an analogue output that can be adjusted onsite. The SWARCO system uses a UTMC interface to communicate with Warwickshire’s existing UTMC Common Database which in turn sends commands to the low energy/high visibility LED signs.

SWARCO has also worked with OTT Hydrometry on a similar system in Warrington. “This is a new solution to an old problem,” says Derek Williamson, Head of Sales for SWARCO Traffic. “We have used our expertise in traffic management technology to design a bespoke system that had previously been used to warn of high winds on viaducts and traffic queues, and adapted the concept to develop an intelligent system providing warnings for dangerous water levels.”

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Bad weather is good news for OTT Hydrometry

OTT Hydrometry, the specialist manufacturer of environmental monitoring equipment, has announced that 2015 was its best year ever in the UK. “Product sales were very good across all ranges,” comments Managing Director Nigel Grimsley. “Our water quality, level and flow monitors all performed very well; as did out meteorological, datalogging and telemetry instrumentation.”

Nigel believes that the effects of Climate Change will increase the need for hydrometeorological equipment. “The potentially devastating effects of severe weather can only be prevented or limited by accurate monitoring with telemetry so that appropriate action can be taken in a timely manner,” he says. “However, it is also vital to be able to model the likely effects of high water and heavy rain before it takes place, so that flood prevention and mitigation schemes can be implemented. Monitoring plays a key role; not just in the creation of these models, but also by supplying near real-time data during adverse weather to improve and optimise warning systems for communities and infrastructure.”

The increased frequency of severe weather events in the UK is clearly having a positive effect on OTT’s sales figures, with the OTT Pluvio2 and ecoLog products selling particularly well. The Pluvio2 is an advanced raingauge operating on the weighing principle, which means that it is able to measure all types of precipitation extremely accurately, whilst also providing intensity data. The OTT ecoLog is a complete system for logging and transmitting water level data in boreholes and surface water.

Summarising, Nigel says: “Bad weather obviously stimulates our business, but continual investment in product development also increases the popularity of our technologies, and the complete monitoring systems that we build make it easier for customers to start collecting and disseminating data.”

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News June 2015

New partner for OTT Hydrometry in Ireland

OTT Hydrometry, the specialist manufacturer of environmental monitoring equipment, has appointed NVM Ltd as exclusive distributor for Ireland. Based in Drogheda in Co. Louth, NVM will be responsible for sales and service in Ireland with immediate effect. “We are delighted with this agreement,” says NVM Managing Director Noel Carr. “OTT products enjoy an excellent reputation around the world, and have a large installed base in Ireland, so, coupled with the introduction of OTT equipment to our existing clients, this represents an excellent growth opportunity for us.”

The OTT product range includes instrumentation for monitoring groundwater, streams, rivers, coastal water and meteorology. In addition to the OTT branded products, the range also includes Hydrolab water quality monitors and Adcon telemetry systems.

“Our business is focused on the accurate and reliable collection of field data, either manually or with logging and telemetry, so there is a good fit between our two companies,” Noel comments. “Our team have already received comprehensive training on the OTT instruments, dataloggers and telemetry systems, and we have invested in appropriate spares, consumables and calibration equipment, so we are now able to provide a full service capability.”

OTT Managing Director Nigel Grimsley says: “NVM’s appointment represents the conclusion of a comprehensive search to find our ideal partner. We have numerous clients in Ireland and have operated a local office with support from our UK based engineers for many years. It is vitally important for our customers to have a local contact for sales and service, so we are delighted to make this announcement.”

NVM Limited Ireland
1st Floor,Unit 13, Boyne Business Park, Drogheda Co. Louth
Tel: + 353 (0) 41 983 7435
Fax: + 353 (0) 41 984 8124 |
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News April 2015

OTT demonstrates latest water monitoring technology

OTT Hydrometry’s latest water quality and level monitoring technologies will be demonstrated at two major events this Spring. First, on 21st and 22nd April, OTT will participate in the International Association of Hydrogeologists Irish Group meeting in Tullamore, Co. Offaly. Entitled: “Integrated Hydrogeology: Contemporary Principles, Policy and Practice,” this event will address many of the strategic issues relating to the management of water resources, in addition to the technical aspects of monitoring. The OTT stand will feature water level loggers such as Ecolog and Orpheus Mini, water level contact gauges/dippers and Adcon/OTT telemetry solutions.

Secondly, OTT will demonstrate a new Phosphate monitor at an Innovation Day at WRc in Swindon on 29th April. This will provide an opportunity to demonstrate the unique advantages of the ‘Cycle-P’ for remote, continuous Phosphate monitoring. “Phosphate levels in water resources are a major cause for concern,” says OTT MD Nigel Grimsley. “Consequently there is a high demand for the Cycle-P, particularly because it is a continuous monitor that can be quickly and simply installed at any location. Battery-powered and able to operate unattended in the field, it can run over 1,000 tests before a field service is necessary to change the reagents.”

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