Water Storage Tank Location?

Here on Whidbey Island, WA, we get lots of winter rain and bone-dry summers.  We're installing 2 x 2500 gal water storage tanks in which to collect rainwater for summer irrigation of our slowly evolving one-acre forest garden.  The water is initially gathered from our roof in IBCs, then moved via garden hose and transfer pump up a small hill to the tanks, which will be next to our barn.  See photos.

We can put the tanks on the shady cool north side or warm sunny south side of our barn.  Our IBCs do not freeze in the winter, so freezing is probably not an issue for the larger tanks.

The south side, with all that all that solar-warmed water, gives us the opportunity to create an interesting small microclimate.  Has anyone done this with their tanks?  We have quite cool springs, so a little radiative warming at night could be quite useful to encourage earlyish and reliable blossoms and fruit set.  Or we may spend our summers trying to hide the tanks from the blazing sun.

Thoughts?

Photo 1: Shady north (right) side of the barn
Photo 2: Sunny south side
Photo 3: 2 tanks ready for installation. 8' diameter, 8' tall.

Wow - that's a tough call! Personally, I would worry that with weather weirding, a frozen tank is not beyond possibility on a "bad year". However, I also feel that plastic tanks should be protected from UV, and they aren't the prettiest things, so I also approve of hiding/disguising them.

If you decide on the sunny side for solar gain, I would build a trellis around/over them and grow runner beans up them for the summer. That would give it some shade in the heat.

A couple of points from somebody with lots of tanks;
- beauty is in the eye of the beholder.
- a tank full of water on a hot day will look better than no tank at all on a cold day!

- I am sure heat from the  sun will have little effect on the water temperature.
- These tanks are usually UV resistant, I have 5000 Gal tanks sitting in the Australian sun for 30 years with no ill effect.
- Only freezing issue may be at the outlet, but if you have protection around that point and get it underground below the freeze level as soon as is needed it may be OK.
- If you have an electric heater just where it is freezing, if it happens you should be OK.

Those are both MUCH appreciated responses.  Thanks so much!  My wife and I have been discussing both at great length, inspiring new realizations as we "war-game" the two options.

One issue we did not mention:  The prevailing winter winds here are from the south.  Our southern neighbor just clear-cut their forested land two years ago.  That's why we have the sun resources to fuel a forest garden, but now we also have horrendous winds much of the winter.  We lost 22 trees last winter just along a 300' front adjacent to our house (see pic).  The water tanks may help wind-protect that now highly exposed 40 year old barn.  Or they could create a chaotic vortex that channels the wind and tears the roof off.  Too complex for us to know!

No one bit on the idea of creating a water tank-fueled warm microclimate, nor have we been able to find such references on the web.  Our guess is that because such large tanks require a pretty good foundation plus some ease of access, that limits one's options for employing the immediately adjacent space as a microclimate.  And as John noted, the temperature difference for such large tanks may not be enough to create a significant microclimate.

We also did a little geometry, and figure that the two tanks need roughly 3x their footprint for foundation and access.  That uses up some pretty valuable sunny space that could otherwise accommodate a rather fortunate guild.  Cherries, we're thinking.

We definitely did not appreciate that the tanks were so UV resistant.  That 30-years-in-Australian-sun comment was priceless.

Given the microclimate option is so limited, we're now inclined to put the tanks on the shady side, both for architectural balance and to preserve the valuable sunny planting space.  But for the immediate future, we'll probably hedge for one year:  Use one tank in a temporary location while we learn how to use it, e.g., how much access does it require, how the plumbing operates, plus the 100 things we don't know we don't know.

Thanks again John and Jay!  Your experiences are so, so valuable us!