In arid Namibia, farms depend on water pumped from underground aquifers into surface reservoir holding tanks, from which it can be distributed for the wellbeing of livestock and humans. Given the large, rural nature of many farms in the region, landowners often have to rely on unskilled staff to monitor and control this key aspect of running an estate. This was the challenge facing Aloegrove, a safari lodge and cattle farm located close to Otjiwarongo, South East of the famed Etosha National Park.
Land owner Johan Doman demanded a high degree of confidence that ‘all is well’ at the borehole reservoir and outlying game waterholes. This meant that staff had to to visit the borehole three times per week to monitor water levels or provide necessary maintenance.
Doman commissioned Wood & Douglas and Namibian-based Desert Technical Solutions (DTS) to design and install remote electronic monitoring which would provide a flexible, reliable and cost-effective solution to maintaining Aloegrove’s water supplies. Aloegrove’s single borehole and open-top reservoir required that an ultrasonic sensor be installed to provide continuous readings of the water level. This still left the problem of a lack of communications or AC power at the borehole.
With no GSM coverage at the borehole site, direct alarm signalling to a mobile phone is not possible. Wood & Douglas therefore installed a local radio network from the borehole to the base station located at the lodge 6.4km away, which does have good GSM coverage. Data is transmitted between the borehole and the lodge using Wood & Douglas Orion modems, and as this link is in the 450MHz range it does not require clear line of sight.
AC power at the reservoir is provisioned by a 12V DC solar-based battery system, with additional circuitry provided by Wood & Douglas to reduce the standby power consumption of the monitoring electronics and radio. All this hardware has been housed in a rugged IP66-rated enclosure, important at Aloegrove where the local baboon troop can be destructive. To minimise power consumption from the solar supply, the outstation only reports once per hour to the base station. This status message sent via the UHF radio link gives the current water level in the storage tank as a percentage value, and also reports the solar battery status. The base station listens to the outstation message, interprets the data, and displays it for the lodge staff. If the outstation sees that the water level has fallen below a user-preset level, or the electricity supply is running low, it sends an alert status message to the base station. If the base station sees an alert status message, or fails to receive the hourly report message from an out station, it sends a warning cellphone text message to the land owner, allowing the problem to be investigated immediately.
Remote, rugged, low-power installation for constant monitoring
Instant alerts via radio and GSM
Reduces maintenance, improves stock management and lowers operational costs
Quote: “The Wood & Douglas and DTS team understand radio and can rapidly interpret a need into a radio-based reality. With the greater efficiency afforded to the team, we are able to spend more time addressing the other needs of the estate and farm, not least the care of our guests.”
Johan Doman, Land Owner, Aloegrove Lodge and Ranch