# Sovereignty Module: Hold the Water

## Complete Cistern and Water Storage Construction: From Pit to Reservoir

Reliable water storage is essential for survival. This campaign covers cistern types, construction methods, waterproofing, and rainwater collection systems.

### Chapter 1: Water Storage Types

| Type | Capacity | Material | Difficulty | Durability |
|---|---|---|---|---|
| Clay-lined pit | 100-500 gallons | Excavation + clay lining | Low | Moderate |
| Ferrocement tank | 500-5,000 gallons | Wire mesh + cement mortar | Moderate | Very high |
| Stone cistern | 500-10,000 gallons | Cut or dry-laid stone + plaster | High | Excellent |
| Brick cistern | 500-5,000 gallons | Brick + cement plaster | Moderate-high | Very high |
| Wooden tank (barrel) | 50-500 gallons | Cooperage (staves and hoops) | High | Good |
| Earthbag tank | 200-2,000 gallons | Filled bags + plaster | Low-moderate | Good |

### Chapter 2: Ferrocement Cistern Construction

Ferrocement cistern (most practical): 1) Excavate hole or build on level ground. 2) Build form: cylindrical (easiest) using plywood or sheet metal. 3) Typical size: 4 feet diameter x 4 feet tall = ~375 gallons. 4) Wrap form with chicken wire (2-3 layers). 5) Add reinforcing wire (tie wire or rebar) vertically and horizontally. 6) Mix mortar: 1 part Portland cement, 3 parts sand, water to thick paste. 7) Plaster mortar onto wire mesh (1/2-3/4 inch thick). 8) Apply from inside and outside simultaneously. 9) Work mortar through mesh (encapsulate all wire). 10) Smooth interior surface (water-tight finish). 11) Cure: keep moist for 7 days minimum. 12) Seal interior with cement slurry or food-grade sealant.

| Dimension | Capacity | Wire Mesh | Mortar Volume | Construction Time |
|---|---|---|---|---|
| 3 ft dia x 3 ft tall | ~160 gallons | 50 sq ft | 3 cubic feet | 1-2 days |
| 4 ft dia x 4 ft tall | ~375 gallons | 80 sq ft | 5 cubic feet | 2-3 days |
| 6 ft dia x 4 ft tall | ~845 gallons | 120 sq ft | 8 cubic feet | 3-4 days |
| 6 ft dia x 6 ft tall | ~1,270 gallons | 150 sq ft | 10 cubic feet | 4-5 days |

### Chapter 3: Rainwater Collection

| Component | Material | Purpose | Specification |
|---|---|---|---|
| Roof (catchment) | Any impervious roofing | Collect rain | 1 inch rain on 1,000 sq ft roof = 623 gallons |
| Gutters | Wood, metal, or bamboo | Channel water from roof | Slope 1/4 inch per foot toward downspout |
| Downspout | Pipe or channel | Direct water to cistern | 2-4 inch diameter |
| First flush diverter | Pipe with valve | Discard first dirty water | Diverts first 1 gallon per 100 sq ft of roof |
| Screen/filter | Wire mesh | Remove leaves, debris | 1/4 inch mesh at gutter and inlet |
| Cistern | Any type above | Store water | Size for local rainfall and usage |
| Overflow | Pipe at top of cistern | Prevent overfilling | Direct overflow away from foundation |

Rainfall calculation: 1) Measure roof area (length x width in feet). 2) Multiply by annual rainfall (inches). 3) Multiply by 0.623 (converts to gallons). 4) Multiply by 0.85 (collection efficiency). 5) Result: annual collectable rainfall in gallons. 6) Example: 1,000 sq ft roof x 40 inches rain x 0.623 x 0.85 = 21,182 gallons per year.

### Chapter 4: Underground Cistern

| Advantage | Disadvantage | Mitigation |
|---|---|---|
| Temperature stable (cool in summer) | Excavation required | Use backhoe or hand labor |
| Protected from freezing | Difficult to inspect | Install access hatch |
| No space above ground | Pumping required | Hand pump or gravity feed from hillside |
| Protected from sunlight (no algae) | Waterproofing critical | Cement plaster interior |
| Hidden from view | Structural load from soil | Arched roof or reinforced concrete |

Underground cistern construction: 1) Excavate hole (larger than cistern by 2 feet on all sides). 2) Lay gravel base (4 inches, compacted). 3) Build cistern walls (brick, stone, or ferrocement). 4) Build arched or reinforced roof. 5) Plaster interior with cement (waterproof). 6) Install inlet pipe (from roof collection). 7) Install outlet pipe (to hand pump or gravity feed). 8) Install overflow pipe. 9) Install access hatch (for cleaning). 10) Backfill around cistern. 11) Grade surface to direct runoff away.

### Chapter 5: Water Treatment

| Method | Removes | Effectiveness | Difficulty | Cost |
|---|---|---|---|---|
| Settling (24 hours) | Sediment, some bacteria | Moderate | None | Free |
| Sand filter (slow) | Bacteria, sediment, some chemicals | Very high | Moderate to build | Low |
| Boiling (1 minute rolling boil) | All pathogens | Very high | Low | Fuel cost |
| Solar disinfection (SODIS) | Most pathogens | High | Very low | Free |
| Chlorination (bleach) | All pathogens | Very high | Very low | Very low |
| Ceramic filter | Bacteria, sediment | High | Low | Low |

### Reference Card

1. One inch of rain on 1,000 square feet yields 623 gallons (this is the fundamental calculation for rainwater harvesting; know your roof area and local rainfall to size your cistern). 2. First flush is dirty (the first rain washes dust, bird droppings, and debris from the roof; a first flush diverter discards this dirty water before it enters the cistern). 3. Ferrocement is the best DIY cistern material (wire mesh plastered with cement mortar creates a strong, waterproof, and long-lasting tank that anyone can build with basic skills). 4. Keep cisterns dark (sunlight promotes algae growth in stored water; underground cisterns or opaque above-ground tanks prevent algae). 5. Always treat stored rainwater before drinking (rainwater is not sterile; boiling, filtering, or chlorinating removes pathogens and makes water safe). 6. Overflow prevents damage (a cistern without an overflow pipe will flood the surrounding area when full; always install an overflow that directs excess water away from buildings). 7. Screen all inlets (a 1/4 inch mesh screen at every inlet prevents leaves, insects, and debris from entering the cistern; this is the simplest and most important maintenance step). 8. Water storage is the foundation of settlement (without reliable water storage, a community cannot survive drought; a cistern sized for the dry season is the most important infrastructure investment).