Planning the system

Plan from behavior

List people, pets, drinking/cooking, dishwashing, showers, toilet use and cleaning. Record normal and conservation-day consumption. Weekend users can refill often; full-timers need resilient storage, filtration, access and spare parts.

Travel changes the design

Heat raises drinking and shower use. Cold demands freeze protection. International travel makes refill quality, adapters and source verification critical. City-water campers need regulated inlet pressure; dispersed campers need tank autonomy.

Space, weight and service

Water weighs about 8.34 lb/US gal (1 kg/L). A 40 gal fill is about 334 lb (151 kg) before tank and hardware. Keep mass low, secure and within axle/payload limits. Leave room to reach every filter, valve, clamp and pump.

Complexity budget

Every filter stage, valve and hidden fitting adds cost, restriction and another failure point. Buy reliability and service access first. Leave capped manifold ports and physical clearance for future changes.

Use

Conservation

Normal

Drinking + cooking

1.5-2.5 gal/person/day

2-3+ gal/person/day

Dishes

1-2 gal/day

2-4 gal/day

Shower

1.5-3 gal/person

5-10+ gal/person

Pet

0.25-1+ gal/day

climate/size dependent

CHAPTER CHECK

• I can explain the purpose and failure mode of each item in this chapter. • I know which manufacturer limit or water-quality claim controls my choice. • I added the valve, access, drain, measurement or maintenance task to my drawing/checklist.