There's always an excitement at seeing kingfishers, perhaps because of their very exotic appearance and their particular lifestyle. Because of this we tend to assume that they're rare and shy. I think their apparent shyness is because of the way they operate, either moving at high speed or spending quite a lot of time sitting still, and of course they live where fish are plentiful, which is isn't always where we live.
Their numbers are governed by the fact that their habitat is mainly linear, either rivers or pond and lake margins so, as they are not flocking or social birds, their territories dictate that they will be fairly thinly spread. However, where there is food and suitable nest sites, there is no reason to assume that they will not live amongst us. Urban waters such as yours, Rose, provided they are unpolluted and have plenty of food (which is quite likely these days) are likely to attract all sorts of birds and give us the fantastic opportunity to watch how they live.
Enjoy them!
Joe