Week 5
Highest water level in 10 years
A lock in the Afsluitdijk was emptied in preparation for the new "hole in the dyke" (for the fish). The 90 year old concrete was found to be in (surprisingly) outstanding condition.
I have called Friesland a "sponge" over the years, little realising that I was so very close to the truth. They call it the Friese Boezem (bosom?) - really a water storage basin.
The Frisian bosom
I tried to read this...but just a bit too technical, I think (even if it was in English).
It gives an historical view of the Friese Boezem - comparing 1876 with 1976 in part and discusses the effect on fish,vegetation, biodiversity and quality of the water.
The level is now maintained at -0.52 metres below NAP (Nieuw Amsterdams Peil - the base line for water measurements).
The Green is average level of the water in 1876 - the Blue is the average in 1976 (maintained at - 0.52 metres NAP).
We studied a bit of this in the Boating Course - in relation to varying water levels and the calculations required if there was some doubt about the boat getting under a bridge if the water level had risen. It is rarely needed in Friesland because of the controlled water level but there is also a Fries Zomer Peil (FZP) of 0.14 metres - which lowers the water level to -0.66m. (Again, no problem for getting under bridges).(Zomer = Summer)
Pumping the water out
This week saw the first operation of "fish-friendly" screws (augers) to try to reduce the water level, which is 100mm higher than normal at the moment in Friesland and even higher in some places "down South".
The steam pumping station at Lemmer is often used to reduce the water level. This new system in Marrum is not yet finished - the screws need to have a cover.

















Can water be sent to other countries that need it? Does your surplus get used?
ReplyDeleteI’ve heard in relation to the type of people that are against Mask wearing etc that it is possibly low intelligence or low socio economic background. Unsure about that.
Always enjoy ready your weekly musings Ken
ReplyDeleteRon’s offering to knit you a beanie to keep you warm
A big thank you for keeping an eye out for Houtrib
Much appreciated
Stay safe greetings to Janny and Ben
Annette and Ron