Will you receive any compensation for the use of your pool?
What do you mean "able to write off the pool" - as tax deduction? as charitable contribution? other?
Assuming you want to deduct the use of pool as charitable contribution...
Please see for reference the IRS publication 526 - http://www.irs.gov/pub/irs-pdf/p526.pdf
Generally, you cannot deduct a contribution of less than your entire interest in property. A contribution of the right to use property is a contribution of less than your entire interest in that property and is not deductible.
Exceptions. You can deduct a charitable contribution of a partial interest in property only if that interest represents one of the following listed items.
A remainder interest in your personal home or farm. A remainder interest is one that passes to a beneficiary after the end of an earlier interest in the property.
Example. You keep the right to live in your home during your lifetime and give your church a remainder interest that begins upon your death.
An undivided part of your entire interest. This must consist of a part of every substantial interest or right you own in the property and must last as long as your interest in the property lasts.
Example. You contribute voting stock to a qualified organization but keep the right to vote the stock. The right to vote is a substantial right in the stock. You have not contributed an undivided part of your entire interest and cannot deduct your contribution.
A partial interest that would be deductible if transferred to certain types of trusts.
A qualified conservation contribution.
A qualified conservation contribution is a contribution of a qualified real property interest to a qualified organization to be used only for conservation purposes.
Qualified real property interest. This is any of the following interests in real property.
Your entire interest in real estate other than a mineral interest (subsurface oil, gas, or other minerals, and the right of access to these minerals).
A remainder interest.
A restriction (granted in perpetuity) on the use that may be made of the real property.
Conservation purposes. Your contribution must be made only for one of the following conservation purposes.
Preserving land areas for outdoor recreation by, or for the education of, the general public.
Protecting a relatively natural habitat of fish, wildlife, or plants, or a similar ecosystem.
Preserving open space, including farmland and forest land, if it yields a significant public benefit. It must be either for the scenic enjoyment of the general public or under a clearly defined federal, state, or local governmental conservation policy.
Preserving a historically important land area or a certified historic structure.
If all qualifications are met - you may deduct the charitable contribution, but
For information about how to figure the value of a contribution of a partial interest in property, see Partial Interest in Property Not in Trust in Publication 561 - http://www.irs.gov/pub/irs-pdf/p561.pd f
I suggest to provide the information above to your tax preparer for considerations.
Sorry for confusion, but that is relatevely complex area of the tax law...
Generally - the answer is yes - you may take a deduction,
but please see above the list of requirements you should met.
In additional - you may not deduct the total value of the pool - because you contributed a partial interest in the property.
also - I noticed that the link is broken - here is corrected link Publication 561 - http://www.irs.gov/pub/irs-pdf/p561.pdf
Let me know if you need any help.