Sale on Fire hydrants?

Over the past few months, there has been a lot of construction on the Eastern Parkway service road between Washington and GAP. In a few years, it will be done and we have a bikeway/walkway median that links to GAP.

Meanwhile, it is just me, or it it unusual to see fire hydrants placed this close together?

Was there a sale on hydrants?

I'm willing to accept that two hydrants are better than one and that it is a densely populated area, but my dog only has so much pee to go around.

My guess is...

The water mains are being replaced in the area. Hydrants need to be switched from the old mains to the new mains. In order to keep hydrants functioning at all times it is necessary to install a new set of hydrants to the new main and then remove the old hydrants when the old main is put out of service. I would guess that the hydrant with the spray painted bonnett is the old one and will be removed eventually.

Thanks. I will pass this good news on to my dog.