Whose responsibility?

If you've been in touch with the news in Alberta at all you will know that we have been getting lots of rain. Thankfully, there has been minimal impact in Edmonton and our basement is staying dry(ish). Our front yard is a different story. Our neighbours had told us that there was a low spot in the front yard and that the previous owners used to pump water out to the street on days of heavy rain. We have had a few really heavy thundershowers and hadn't noticed any standing water, so we weren't too worried about it. Well, after a solid day of rain earlier this week, this is what the front lawn looked like.

Not really a big deal in our opinion, since it is well away from the house and only on our grass. Our neighbour seems to feel otherwise, as she was out there using a juice pitcher and a bucket to move the water onto the street. I understand that her plants could drown if the water stays there for a while, but things usually dry up pretty fast around here.

With the previous owner of our house setting the precedent on pumping out the water, we got the feeling that maybe we were expected to keep doing it. Is this really our responsibility? The low spot is on both of our properties and it's the uneven sidewalk that is really holding the water in. Should we take steps to fix it? Let the neighbour deal with it? Or can we call the city to fix the sidewalk? For now, I think we are just going to hope that the precipitation stays to a minimum.