Poway's lake adjoins a city park, and is free for Poway residents.
I think they allow free access to non-residents on weekdays, but charge on weekends.
It's a bit more park/less lake for my taste, but then I'm not a resident.
We were astonished to see so many birds. Not just ducks, but vultures,
osprey and a bald eagle.
We walked around the lake in April 2024 and found it to be beautiful at 8-11 am.
But I'd advise caution, carrying water, and sun protection later in the day.