I'm looking for good references and information on sizing and designing gravity fed water systems. 

Can you share info on your favorite and most useful references or experiences on this subject.

particularly pertaining to dealing with too much pressure (surge tanks/pressure breaks/integrating microhydro), warm water issues (hot and thermal springs), freezing, constant flow, sediment loads and filtering, domestic use, avoiding air locks.

any anecdotes or recommendations are welcome.

currently, here's some links and articles I've found.
I consider them supplemental to the Keyline design system of farm layout for use when you have developed water resources at head pressure.

a link to several articles and gravity flow system calculators
http://www.itacanet.org/itaca/sections/water/gravity-flow-water-systems/

gravity fed water system links
http://www.itacanet.org/doc-archive-eng/water/Gravity_Fed_Water_System.pdf
http://www.rwssp.com/Publication/TAN%204.9%20Water%20Supply%20-%20Gravity%20Fed%20Systems.pdf
http://www.scribd.com/doc/35189494/How-to-design-a-Gravity-Flow-Water-System
http://www.lifewater.org/resources/rws4/rws4d1.pdf
http://www.agf.gov.bc.ca/resmgmt/publist/500Series/590304-5.pdf
http://www.calctool.org/CALC/eng/civil/hazen-williams_g
http://watershapes.com/images/archives/indexed/WaterShapes200301-steve-gutai-surge-tanks-hydraulics-water-in-transit-capacity-plumbing.pdf


micro hydro power links
http://www.homepower.com/articles/microhydro-power/basics/what-microhydro-power
http://www.level.org.nz/energy/renewable-electricity-generation/micro-hydro-systems/
http://pioneer-sys.net/microhydro.htm
http://en.wikipedia.org/wiki/Micro_hydro
http://www.pumpfundamentals.com/micro-hydro.htm

also a book title reference from Art Ludwig's Water Storage
A Handbook of Gravity Flow Water Systems by Thomas D. Jordan, Jr. Intermediate Technology Development Group. 1980
http://books.google.com/books?vid=ISBN0946688508

How to design a gravity flow water system by Santiago, Santiago
http://books.google.com/books?id=IpIO36NMKNYC&printsec=frontcover#v=onepage&q&f=false

Slightly off topic mother earth news article on off-grid water systems
http://www.motherearthnews.com/nature-and-environment/off-grid-water-systems-zmaz00jjzgoe.aspx#axzz2fSABSJAF

Here's a few additional references specific to springs.

I encourage people to always consider the impacts of withdrawal on any riparian systems fed by the spring. for example, in the western US, you could initiate some severe erosion issues by starving a channel or slope wetland of it's supply during the growing season. The takehome message is be thoughtful, do your due dilligence, monitor for feedback and adapt/iterate based on this info.

http://www.fs.fed.us/eng/pubs/pdf/waterguide/hi_res/springs.pdf http://www.lifewater.org/resources/rws1/rws1m.htm
http://www.nrcs.usda.gov/Internet/FSE_DOCUMENTS/nrcs144p2_030354.pdf http://www.wellwater.bse.vt.edu/files/WF4%20spring%20devt%20and%20prot.PDF alternative to spring boxes
http://www.lboro.ac.uk/well/resources/technical-briefs/34-protecting-springs.pdf

a video option http://www.youtube.com/watch?v=3jz0m3HFjgs
cheers,
Neil