must...

be

constructed

using

local

labor.

be

constructed

using

locally

available

materials.

use

generic

suppliers

rather

than

specialized

components.

operate

without

electricity.

minimize

use

of

valves

to

reduce

costs.

minimize

use

of

moving

parts.

be

robust

and

resilient.

be

optimized

for

low-cost

and

high-performance.

be easy to construct using low precision construction techniques
use high rate processes to minimize construction costs and facility footprint

use

unit

processes

that

are

observable

whenever

possible

(no

sealed

reactors).

be

possible

to

operate

without

doing

math.

use

chemical

dosages

that

are

set

directly.

be

maintainable

by

one

person.

have

a

direct-reading

indicator

of

plant

flow

rate.

have

a

chemical

dosing

control

point

close

to

flocculator.

have

no

small

parts

that

can

be

easily

lost.

have

removable

parts

for

inspection

and

maintenance.

be

enclosed

in

a

building

to

provide

protection

from

sun

and

rain.

be

sized

so

that

all

tanks

are

accessible

by

a

human

for

inspection.

include

provisions

so

that

the

operator

can

receive

appropriate

feedback

for

every

step

of

the

treatment

process