Juan

Thanks for your email. I am posting this reply to the list because I am not qualified to opine on this matter.

My difficulty is that I reside in an area where these matters are covered by regulations established by local, provincial and federal governments, who have benefitted from experts with long accrued experience. Capacity of storage tanks supplied by pumps seems to be dependent on local experience, e.g. of reliability of primary and back-up energy sources, provision of reserve pumps, availability of water, available finances to provide good security (wealth), and on the consequences of supply failure (insurance). In my area we are blessed with comparatively good and reliable energy and mechanical systems, and abundant water, but large costs and insurance claims in the event of rare disasters such as inadequate storage during fires and accidents. In Ontario, standards are available from the Ontario Ministry of Environment and Energy, and for higher education, we seem to use conservative approaches such as those espoused by Terrence McGhee in his book "Water Supply and Sewerage".

Please let me know if you find fresh approaches of practical value.
Thanks again for your question and I hope that the list can help you.
Regards.
bill james