I’m sorry but I’m not going to be able to give you much good news.
The fact that you may have bought the property 13 years ago and this problem existed at that time, is not relevant. You buy the property inheriting its problems.
If this were to have drained across the car park for 20 years, there were, then you could claim an easement for drainage under the Prescription Act.
However it has changed direction for whatever reason, it is your pond and you are responsible for debating the nuisance.
However even though you may be able to claim an easement, it must not cause nuisance which is what they are suggesting.
You would also be responsible for any damage caused by the water drainage or for the removal of any algae for any injury if anyone slips on the algae.
I don’t know what they are asking you to contribute one third towards.
Can I clarify anything else for you?
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