Investigation of the Efficacy and Cost Benefits of Modern Technology Communications Media for Remote Data Collection and Site Interrogation in Scotland and Northern Ireland
Issue 1
July 2006


Background to research

SEPA and DARDNI both have hydrological data gathering systems which are used within both organisations for assessing the flows and levels of water courses, lochs and tides. The information gathered by these systems provides vital data for the operational decision making within both SEPA and DARDNI. Furthermore within SEPA the data supports the Flood Warning Service provided to the public by allowing real time data to be gathered either prior to or during a flood event.

The data is gathered by a central information system (or systems) from a number of remotely located sites. The sites are connected via electronic devices, referred to as remote outstations to the central information system via a communications service provider. The existing communications technology has mainly been provided through the BT Public Switch Telephone Network (PSTN). For this technology each site has a direct PSTN telephone line connected between the central system and the remote outstation. Both SEPA and DARDNI do have a small number of sites which use other  communications bearers. SEPA have moved forward on some sites to the use of second generation mobile phone services (GSM).  DARDNI have introduced radio technology to communicate with a small number of their remote sites.

For this project the overriding key requirement is to determine the range of more modern communication technologies which are now available to provide this service and to then compare them with the existing service provision. Furthermore, particularly for SEPA consideration will be made to the range of obsolete remote outstations which will need replacing over the next few years.  Other factors will be considered in the research and analysis of this project which will include the sustainability of the communication technologies and the site power provision which will include an analysis and comparison of the existing power supply provision with renewable energy sources.

SEPA and DARDNI consider that there are a number of key business drivers which will require the hydrological data gathering system to be improved. These drivers are::
Objectives of research

The objectives of the research are to provide SEPA and DARDNI with a clear vision of the ways forward in choosing the most appropriate and cost effective communications technology which meet the business drivers.

A Remote Telemetry Communications Strategy  will be produced providing the overall policy decision requirements based on a cost comparison of the available technologies over a 15-year life cycle.

A Remote Telemetry Communications Selection Tool will be produced which will allow SEPA and DARDNI to consistently choose the type of communications technology required for a particular sites location.

A detailed technical report of the findings of the research will also be produced.

Key words and definitions:

Poll Remote The timing by which the Central Hydrological System gathers data from a remote
Poll Types SEPA Normal Poll – Data values requested from the remote outstation once every 24 hours.

SEPA Normal Poll – Data values requested from the remote outstation once every 24 hours.

SEPA Event Poll – Data values requested from the remote outstations once every 60 minutes for a period of 2 days.

SEPA Alarm Dial Up – The alarm condition messages which are reported from the remote outstations on occurrence.

DARDNI Normal Poll – Data values requested from the remote outstations once every 7 days.

DARDNI Voice Message Poll – Telephone calls made to the remote outstations which generate automated voice messages which provide the status and values of the measured hydrometric items on a particular site.
Protocol The structured method by which data is retrieved from a site. Generally each remote outstation supplier provides their own proprietary communications protocol.
DNP3 A new standard protocol which can be used across a wide range of remote outstations from different suppliers.
PSTN Public switched telephone network
GSM  Second generation mobile phone networks
GPRS  General Packet Radio Service – provided on mobile phone networks.
TG1150 The existing remote outstation type used within SEPA
D7000 A new range of remote outstations which SEPA are assessing for the future.
Data Logger A particular type of remote outstation used for on site recording of data. SEPA have a number of Dynamic Logic TG 1150 outstations and Isodaq data loggers and DARDNI have a number of OTT data loggers.
Portability A term used to describe the capability of equipment to deployed and then re-deployed as required at different sites.
Baud Rate The data transfer rate from the remote outstation to the central gathering system measured in digital bits per second.
Instrument The field device which is used to measure the required site data, such as river flow, river levels, water quality and rainfall.
Geo-referencing Assigning co-ordinates to an image file, usually by inputting the co-ordinates of known or prominent features.
NPV This is the summation of the 15-year life cycle annual stream of discounted total costs, for each communication technology, giving the equivalent total value for today. This is done by discounting the 15-year life cycle annual costs using an appropriate discount rate, which for this project will be 3.5%.
CDMA Code Division Multiple Access: A technology for digital transmission of radio signals between, for example, a mobile telephone and a radio base station. In CDMA, a frequency is divided into a number of codes.
SWOT An Options Analysis process. The SWOT methodology allows the strengths, weaknesses, opportunities and threats to be listed and then compared.
Energy density The energy density of a battery is the amount of energy a kilogram weight of a battery could deliver, it is expressed in watt-hours per kilogram (Whr/Kg).
Discharge rate The discharge rate of a battery is often expressed in terms of the C-rate.  This is the current drain that would discharge a battery in one hour.  This would, usually, be a very high load to impose on a battery and effects characteristics such as the discharge curve so most battery manufacturers provide data for a reduced discharge rate of 0.2C or 0.1 C.  Consequently care is needed when comparing data from different manufacturers.

Document Structure

This document comprises of 3 volumes as described below:
Outputs from the project:
Volumes I, II, and III
Pilot Catchment Assessment report
Telecoms Site Selection Tool: Configuration Document  
together with electronic version of Telecoms Strategy Model (excel) and Telecoms Site Selection Tool (software and model)
are available from the Foundation in electronic format on CDRom at £20.00 + VAT or hard copy set (with electronic outputs) at £75.00, less 20% to FWR members.

N.B. The outputs are available for download from the SNIFFER Website