Information

Dr. William James

I read your e-mail in the epanet users list about the several books of hydraulic, hydrology, urban hydraulic etc.

I work in Empresas Publicas of Medellin in the Water Planning Division and in this moment I am working in a study that object is planning capacity of water storage tanks in distribution networks.

In our case normally use the 40% of the demand mean in a day to calculate the storage volume, this criteria include the variations in the demand and reserve storage for emergencies. I think that technical advances on this subject have been modest.

My question is if you know some papers of journals or books about this theme.

I like to know, What is the situation when the water storage tank is supply from pumps. What reserve do I need.

Thanks, best regards
Juan Carlos Herrera Arciniegas
jherrera@epm.com.co

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

Juan,

There are a lot of rules used for storage tank sizing and many
interpretations of those rules. In general they can be summarized as: A
storage tank should have volume equal to the sum of:

1. equalization storage (depends on how you operate system),
2. fire flow (depends on supply capacity compared with max fire demand
plus max day demand),
3. emergency storage (depends on reliability of source of supply).

Tom Walski