Engineers Without Borders

4-14-08 Project Meeting

May 1, 2008 at 5:22 pm | In Meeting Minutes | Comments Off

General:

Sunday afternoon is the deadline for summer trip design plans.

Trip will leave right after exams.  3-4 students will go for at least two weeks.

Questions:

How much water needs to be supplied to each tank?

·         15L per person per day hauled up already with buckets.

o   Only used for drinking, cooking, household cleaning (not laundry)

o   We want to supply water for laundry as well to prevent stream pollution

·         We will go with 50L/person/day to be safe

·         Tanks must be sized for water to be used over a 12hour period.

Limitations

·         38L/person/day maximum from Don Rojelio’s spring during the dry season.

 

Other issues to consider:

·         Concrete tanks were asked for instead of plastic.  How do we build them?

o   Foundation:

§  Cinderblocks(cheaper) vs concrete(stronger)

§  Filling cinderblocks (gravel or low density concrete)

o   Waterproof coating inside?

o   How much rebar do we use?

o   How do we cap the tank yet let it remain open to the atmosphere?

·         Should we include a viewing window so people can see the tank level?

o   Clear PVC? Might get brittle and break with UV exposure (drain tank)

o   Float with weight outside the tank? (used on city tanks here)

·         How do we deal with overflow? Shutoff valve? Just let it drain once full?

·         Shutoff valves?

o   Maximum of 81psi, so a regular (toilet style) shutoff valve is fine.

·         Shower for landowner to attain permission to use her land.

o   Use a small pipe for her shower, build a tank big enough for 2 showers to limit usage

(25 gal or more, 55gal drum).

·         Polyducto vs PVC

o   Polyducto: 125psi rating, 100yrd sections, cheaper, will use this

o   PVC: more confident about pressure, 6m sections, more expensive

·         Should we wrap metal fittings with a moisture barrier?

·         Should we use two pipelines? (pipe is so far our largest expense, so it would be best to avoid this)

·         Should we use handpumps to get water out of tanks (because they will be so low to the ground).  Do we need a siphon?

·         How do we design the wash station?

Things to be determined by Sunday:

·         Hydralic design for piping

·         Tank specs

·         Wash station design