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Boston Public Garden lagoon update

On Wednesday, August 19, the Boston Parks and Recreation Department began draining the Boston Public Garden Lagoon because the water has become unsafe for wildlife who inhabit the pond, particularly the ducks.

The drainage process took about 2-3 days, and the lagoon has been fully drained and sediment removal has begun. The sediment removal process will be completed by the middle of next week. Once all the sediment has been removed, our maintenance staff, supported by a lake and pond management company, will begin refilling the lagoon. We expect that the lagoon will be refilled by next weekend (the weekend of August 28 - 30).


The unusually hot, dry summer has encouraged bacteria and algae growth in the lagoon. We believe one contributing factor to this bacteria growth is the fact that the Swan Boats are not in operation this year due to public health precautions. The Swan Boat paddle wheels typically introduce oxygen into the lagoon and create turbulence that discourages unwanted growth. 

The Parks Department engaged a lake and pond management company to treat the lagoon throughout the month of July. When we saw little improvement after weeks of testing and treatment, we made the decision to fully drain the lagoon, remove sediment at the bottom, and refill it.

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