Why some Halifax-area beaches keep closing — and what's being done to keep them open

A Dartmouth, N.S., councillor says work is underway to keep city beaches safe for swimming, including discouraging pigeons from roosting nearby and collecting storm water so it doesn't run into the lakes.

But Coun. Sam Austin admits the amount of development around some lakes, such as Lake Banook in Dartmouth, poses significant challenges to water quality this time of year.

Several lakes are currently closed in the Halifax Regional Municipality due to high levels of bacteria, while many others have warnings for blue-green algae. The beaches that are closed include Papermill Lake Beach in Bedford and Kearney Lake Beach and Chocolate Lake Beach in Halifax. 

People are also being asked to avoid contact with water in the Halifax Harbour because a pump failure is causing wastewater to flow into the harbour.

CBC Radio's Information Morning spoke with Austin, who represents District 5, to hear why some beaches seem to close more than others and what's being done about it.

His conversation with guest host Bob Murphy has been edited for clarity and length.

Listen to the full interview here:

It certainly seems that lake closures are becoming more frequent in the HRM. Where could these issues be coming from? 

Urban lakes face a lot of different pressures. If you think about a lake out in nature, you've got a large riparian zone around it, full of trees and understory vegetation, and you get a lot of filtering through there. In the urban areas, a lot of that natural system is removed and been built on and a lot of your wetlands that are filters are gone.

You get a lot more of a rapid transfer of whatever is on the land directly into the lakes, and for us that's a lot of extra nutrients and it can be pollutants and those can cause bacteria blooms and also feed blue-green algae. Those are the challenges that you have with urban lakes. 

This has been on the radar for a little while, hasn't it? Because the city commissioned a report back in 2019, a pollution source control study, for Lake Banook and Lake Micmac. What did that study find? 

So Banook and MicMac … if you looked at it over a several year span, you could see an uptick in the number of closure days at both lakes. The study basically came back and said, yeah, you do have some nutrient loading, a lot of it's coming off of our roadways actually. It gave a couple of specific recommendations for the municipality as what we could do, several of which have been acted upon, some of which are still in process, and some of which are going to be long-term things.

The measures included putting netting on the bridge [on Highway 111] to keep the pigeon flock that was there from roosting directly over the water. We had changes in how we do street sweeping so that we're gathering up more of the nutrients off the road rather than allowing them to be flushed down into the lake, changing how we manage storm water. We had a pilot rain garden project there on Prince Albert Road to direct storm water into the rain garden and let it do some natural filtration before going into the lake. 

The ones that you have been working on and actually have implemented, are you confident that they're making any difference? 

I think they do make a difference. It's a question of degree. We can't change that the lakes' drainage area has been so heavily developed. If you go down on Lake Banook, looking at the shoreline you've got a road on one side with piled up rocks to support that roadway and then you've got lots of manicured lawns all around the lake as well. There's not much of a natural system to try and buffer the challenges we're throwing at the lake. So that means we really have to pay a lot of attention to these other things that we can control more easily. 

How much are you considering these implications when you're approving development in the city? 

A lot of what's along Lake Banook wouldn't be allowed today. We have a 20-metre setback buffer from watercourses when it comes to new development so a lot of what was built on Banook would just not be allowed today. The hope is that those kind of measures preserve enough of the natural system so that you have less of this sort of issue.