BACKGROUND
EFlows are defined as the quantity, frequency, timing, and quality of water and sediment flows necessary to sustain freshwater and estuarine ecosystems and the human livelihoods and well-being that depend on these ecosystems (Amended from Brisbane Declaration (2007).
DRIFT was developed for use in the environmental flows assessments for the Lesotho Highlands Water Project. The Building Block Methodology had been approved for use in the assessments but it became clear early on that a single recommended flow would be useful in the process of negotiating the environmental flow releases, and the decision was made to rather follow a scenario approach. This proved a wise decision, as during negotiations over 30 scenarios were generated using DRIFT before a environmental flow releases could be agreed on by all of the parties. This process is outlined in BROWN, C.A. and WATSON, P. 2007. Decision Support Systems for Environmental Flows: Lessons from Southern Africa. Journal of River Basin Management. Volume 5, Issue 3. 169–178.
DRIFT was developed almost 30 years ago and has been used and applied in approximately more than 50 projects to date in 20 countries. It was first used on the Lesotho Highlands Water Project, a major inter-basin water transfer project that supplies water to South Africa from Lesotho. It was initially developed as an Excel based decision support tool but in 2006 was moved over to a Dephi platform.
DRIFT has been used on ~60 projects on three continents, mainly southern and central Africa and Asia. Countries in Africa where it has been used include: Angola, Botswana, Lesotho, Malawi, Mozambique, Namibia, Tanzania, Zambia, and Zimbabwe. Countries in Asia include Nepal, Pakistan, and in the Mekong Basin (Laos, Myanmar, Cambodia, Thailand and Vietnam). It has also been used in Peru.
Yes, the use of DRIFT has been documented in ~20 peer reviewed papers including journals such as The International Journal of River Basin Management; African Journal of Aquatic Scientists; Hydrological Sciences Journal; Freshwater Biology; Rivers Research and Application; and Water SA.
DRIFT is widely recognised as a robust environmental flow assessment tool by aquatic scientists and conservation organisations (e.g., World Wildlife Fund (WWF); International Union for the Conservation of Nature (IUCN)); donor organisations such as DFID; GIZ, and funders of basin planning and hydropower projects (e.g. Asian Development Bank (ADB), International Finance Corporation (IFC), World Bank (WB). DRIFT has also been used on several large transboundary water projects and is therefore familiar to water commissions such as the Okavango Water Commission (OKACOM); Kunene River Joint Permanent Technical Committee (Angola/Namibia);Indus Water Commission (Pakistan/India); Zambezi Water Commission (Zimbabwe/Zambia) and the Mekong River Committee (MRC).

APPLICATION
This depends on the experience of the users – with both holistic environmental flows assessments and computer software – and the complexity of the study. An experience EF practitioner should be able to apply DRIFT in a simple assessment for the first time with minimal training and use of the information on the website. As with all software, practice is recommended embarking on more complex applications.
Specialists facing DRIFT for the first time usually require some explanations of the concepts of DRIFT and response curves, and some guidance in navigating the software for the purposes of populating specialist information. That said, hundreds of specialists have used DRIFT successfully with minimal on-project training.
Yes. DRIFT has been applied successfully for the Pangani Estuary (Tanzania), the St Lucia Estuary (South Africa) and the Mekong Delta (Vietnam). It is worth noting however, that the quality of an environmental flows assessment for an estuary is highly dependent on the quality of the hydrodynamic modelling, which must be done outside of DRIFT.
Yes. DRIFT has been applied successfully for the Lake Sibaya and the Pongola Floodplains (South Africa), the Okavango Delta (Botswana) and for the Tonle Sap (Cambodia). It is worth noting however, that the quality of an environmental flows assessment for a large complex wetland or lake is highly dependent on the quality of the hydrodynamic modelling, which must be done outside of DRIFT.
Yes, DRIFT can be run at a daily or an hourly-time step. The latter is required for the evaluation of peaking power operations.
DRIFT uses surface expression of water. Groundwater contributions would need to be factored in by the hydrologist or hydraulics modellers that provide the data to DRIFT.
DRIFT can used to evaluate ecosystem response to scenarios that capture changes in the distribution and volumes of water or sediment flows or water levels, in the levels of utilisation of natural resources and/or the barrier and operational effects of water resource developments.
DRIFT DSS outputs are exported to MSExcel and from there can be used to in reporting.
Yes. DRIFT has been used successfully on almost all types of streams.
No. Modelling of the effects on climate change on flow requires rainfall runoff modelling.
DATA NEEDS
DRIFT requires daily or monthly time-series data for hydrology or hydraulic parameters. The recommended minimum length dataset is 10 years, but the longer the better and DRIFT can be run with a shorter time-series
DRIFT is not optimal using monthly data.
Yes. DRIFT has a dedicated social module.
Social considerations are incorporated into DRIFT in a similar way as ecosystem considerations, through the use of indicators, composite indicators and response curves. The process for this is covered in the User Manual.


SPECIFICATIONS
Operating system: Windows 7 or 8.
Minimum RAM: 4 GB.
Recommended specification: Intel I5 2 GHz.
Disk space required: 10 MB for software, and a minimum of 600 MB for the data files.
Other software required: In order to view the maps in the SETUP section of the DSS, Google Earth must be installed on your computer.
DRIFT currently does not run on Apple computers.
DRIFT does not automatically generate response curves. These are created by the user, and the computer cannot be used for other things while this is being done. However, the computer can be used for other things when DRIFT is analysing flow scenarios. This will, however, slow down the analysis process.
The results are readily exported to MS Excel, and sample files are provided along with the DRIFT software.
Yes. A deliberate decision was taken not to include hydrological modelling as part of DRIFT, but rather to specify what hydrological data would be needed. This allows the hydrologists to work with hydrological models already set up for the basin of interest, or ones that they feel are best suited to the work at hand.
RESOURCES
Recommended skills include a familiarity with modelling software and a working knowledge of the field of environmental flows.
This is entirely dependent on level of experience with both holistic environmental flows assessments and with computer models. An experience EF practitioner should be able to apply DRIFT in a simple assessment for the first time with minimal training and use of the information on the website. As with all software, practice is recommended embarking on more complex applications.
The DRIFT website has several video tutorials that explain key aspects of DRIFT. The annual subscription includes participation for two people in two on-hour online DRIFT Q and A sessions. Please check the website for the dates of upcoming sessions. EFlows and DRIFT training courses are also offered online from time to time, please check the website for the dates of upcoming courses. Additional personalised training and support is available at a cost of $100 per hour for individuals and US$150 per hour for groups up to 4.
Yes. DRIFT training courses for various levels are offered on-line. Please check the website for the prices and dates of upcoming courses.
OBTAINING & USING DRIFT
2018 is DRIFT’s launch year. We accept that there may be some challenges and teething problems, if you are prepared to meet us half way, then DRIFT launch special subscription costs for 2018 are:
International commercial users:
o US$ 400.00 for an annual license for installation on a single computer
o US$ 750.00 for annual licenses for installation on five different computers
SADC citizen commercial users:
o US$ 200.00 for an annual license for installation on a single computer, subject to verification of SADC citizenship
Bona fide academics: Free
Bona fide students: Free.
Applicants wishing to obtain DRIFT should submit proof of payment. Thereafter a ‘login key’ and the DRIFT interface software will be sent to you via email. Academic users should complete the online application form, and submit it for approval. Once approval is obtained, a ‘login key’ and the DRIFT interface software will be sent to you via email.
A user manual and various tutorials on using DRIFT are available under the Resources tab on the DRIFT website. Commercial subscription also includes two SKYPE sessions of up to 1 hour. Users can also purchase additional assistance at $100 per hour by contacting us via email and we will respond directly?
For more information
Feel free to send us a message and we will get back to you.