This episode feels like an end of season finale, as at that time, it pretty much was. The next episode wouldn't be made for another 4 years, on the 10th anniversary of the series.
Dibley potentially being evacuated to make way for the new reservoir is reminiscent of the Welsh village of Capel Celyn, which was flooded in 1965 when the Llyn Celyn reservoir was created to supply water to Liverpool and the Wirral.
It takes around 25 seconds for the protesters to sing the first verse of '100,000 Green Bottles Hanging on the Wall'. At that rate, the whole song would take about a month to finish.