Dam!

The dam burst.  The one that supplies our electricity (via a water turbine) and our domestic water.  It's still a bit of a mess up there but with a concerted bit of cobbling I've now got both domestic water and electricity working.  In fact the electricity is working better then before.  This is mainly due to the strong steady rain we've had for the past 3 days but a wee bit of it is because the water intake has improved.  The dam was too big for requirements (part of why it eventually collapsed) and the water inlet was 1m under the surface of the water.  The inlet is constructed from 4" pipe (the pipe down to the turbine is 6").  In an attempt to allow a filter to be placed in the inlet it was constructed using a t-junction with the inlet pointing vertically up (the horizontal portion was blocked off).  A motley collection of pipes and netting was then placed in the inlet to try and stop leaves, twigs and frogs getting into the turbine.  The effect of all this was a reduction in water flow and continual blocking of the inlet.  Any benefit produced by the extra-large dam was lost in the convoluted inlet.

I've now unblocked the horizontal inlet which is still below the reduced level of the dam and tried out a couple of filters.  My first attempt used an old scallop net and it kept out the leaves but, since the flow rate at the inlet is so high, the net was sucked tight against the inlet and the small surface area was blocked by the leaves it was filtering within 48 hours.  The next attempt was a 1m tall dunce's cap fashioned out of a rusty but just-about-pliable metal grill.  This fits over the inlet and stands proud providing a much greater surface area for filtering.  It seems to be working and we've been getting a steady 3A for the past 24 hours.  There are no photographs of the new filter because it was installed in the middle of the strong steady rain and everything was just too damn wet.