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pat_k

(14,473 posts)

7. And of course, painting it a dark color added heat.

Tue Jun 16, 2026, 05:17 PM

Tuesday

A bonus from the algae's perspective.
https://www.yahoo.com/news/us/articles/american-flag-blue-pipes-4-133546018.html

The timing—just days after the pool was refilled—has prompted debate over whether the darker coating could be playing a role.

Darker surfaces absorb more sunlight and heat than lighter ones, which in shallow water can raise temperatures and increase the energy available for algae growth—potentially accelerating reproduction rates.

Lowe said this effect could be significant, as darker surfaces effectively act as a heat source. "The darker an object the more light it absorbs and the warmer it gets," he said, adding that this can create "perfect conditions for algae to bloom" in shallow, sunlit water.

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Emrys Talitha

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Just want to break this out as a question, what was the water source that filled the reflecting pool? [View all] 31j20b3 Tuesday OP

Its basically a tidal basin Potomac brackish water Lochloosa Tuesday #1

Well that's an answer that accounts for what was seen 31j20b3 Tuesday #3

Both the tidal basin and city water. Here's a really good explanation of how the whole system works, Ocelot II Tuesday #2

Filtration wouldn't rid the water of nutrients it would require biological consumption 31j20b3 Tuesday #5

;-{) Water is pumped from the Tidal Basin, an inlet of the Potomac River, to the treatment plant....... Goonch Tuesday #4

With all the water fowl Jerry2144 Tuesday #6

And of course, painting it a dark color added heat. pat_k Tuesday #7