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Task 3: Build Water Storage Structures - Project Template

Part of: Plan Section (Vision → Plan → Reality)
Type: Template/Playbook for Small Plot Restoration
Status: Template - Customize for Your Project

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Purpose​

Water storage structures bridge the gap between when rain falls and when water is needed. By capturing and holding water during surplus periods, you ensure availability during dry seasons and droughts.

This is a template. Customize storage types, sizes, and designs based on your specific water needs, site conditions, and budget.

🎯 Non-Negotiables (Science Consensus)​

These must be followed - they are based on scientific and practical consensus:

  1. Overflow Management Required: All water storage systems must have overflow management. Uncontrolled overflow can cause erosion and flooding.

  2. Water Quality Protection: Storage systems must protect water quality. Contaminated water can harm plants, soil, and ecosystem health.

  3. Legal Compliance: All water storage structures must comply with local regulations. Permits may be required for larger structures.

  4. Safety: Storage structures must be safe. Dams and large structures require proper engineering and safety measures.

  5. Maintenance: Storage systems require maintenance to function effectively. Plan for ongoing maintenance.

🔀 Options & Pathways​

Pathway A: Professional Engineering and Construction​

When to use: Large structures, dams, when safety is critical, have budget, want professional validation

Approach:

  • Professional engineer design
  • Professional construction
  • Comprehensive permits and approvals
  • Professional inspection
  • Higher cost but safe and reliable

Pros:

  • Most safe and reliable
  • Professional validation
  • Meets all regulations
  • Suitable for large structures

Cons:

  • Higher cost (€10,000-100,000+)
  • Requires professional expertise
  • Longer timeline
  • More complex

Pathway B: DIY with Expert Consultation​

When to use: Smaller structures, limited budget, want to learn, have some skills

Approach:

  • Expert consultation on design
  • DIY construction with guidance
  • Simple structures (tanks, small ponds)
  • Community involvement
  • Lower cost

Pros:

  • Lower cost (€500-10,000)
  • Educational value
  • Community engagement
  • Accessible

Cons:

  • May need expert review
  • Requires skills
  • More time investment
  • Limited to simpler structures

Pathway C: Simple Tank Systems​

When to use: Small projects, limited budget, want simple solution, immediate needs

Approach:

  • Pre-fabricated tanks
  • Simple installation
  • Minimal infrastructure
  • Quick deployment
  • Lowest cost

Pros:

  • Lowest cost (€200-2,000)
  • Simple and quick
  • Accessible
  • Flexible

Cons:

  • Limited capacity
  • May need multiple units
  • Less integrated

Pathway D: Hybrid Approach​

When to use: Most projects - balance of professional and DIY methods

Approach:

  • Professional design for critical aspects
  • DIY for simpler components
  • Expert consultation as needed
  • Mix of professional and community work

Pros:

  • Good balance
  • Cost-effective
  • Flexible
  • Engages community

Cons:

  • Requires coordination
  • May need ongoing consultation

📋 Implementation Steps​

Step 1: Determine Storage Needs​

Review water budget:

  • Refer to Assess Water Needs
  • Identify monthly deficits requiring irrigation
  • Calculate total volume needed
  • Consider peak demand periods

Storage capacity calculation:

  • Sum of deficit months = minimum storage
  • Add 20-30% buffer for variability
  • Consider multiple years of drought
  • Balance need vs. cost

Other factors:

  • Fire suppression requirements
  • Wildlife watering needs
  • Multiple use benefits
  • Future expansion plans

Step 2: Choose Storage Type​

Above-ground tanks/cisterns:

  • Capacity: 50-50,000+ gallons
  • Best for: Active rainwater harvesting, near buildings
  • Advantages: Easy installation, movable, various sizes
  • Disadvantages: Visual impact, freeze risk, space requirements
  • Cost: €0.50-3 per gallon

Below-ground cisterns:

  • Capacity: 500-50,000+ gallons
  • Best for: Large storage, freeze-prone areas, aesthetics
  • Advantages: Temperature stable, hidden, no freeze risk
  • Disadvantages: High installation cost, difficult to inspect/maintain
  • Cost: €2-5 per gallon installed

Ponds:

  • Capacity: 50,000-1,000,000+ gallons
  • Best for: Large sites, wildlife habitat, multiple uses
  • Advantages: Lowest cost per gallon, habitat creation, aesthetics
  • Disadvantages: Evaporation, requires space, permitting
  • Cost: €0.10-0.50 per gallon

Bladder tanks:

  • Capacity: 100-10,000 gallons
  • Best for: Temporary or mobile storage
  • Advantages: Collapsible, portable, quick deployment
  • Disadvantages: Limited lifespan, potential punctures
  • Cost: €1-2 per gallon

Natural features (enhanced):

  • Examples: Springs, seeps, natural depressions
  • Best for: Existing water sources that can be developed
  • Advantages: Work with nature, minimal construction
  • Disadvantages: Limited control, variable yield

Step 3: Site Selection for Storage​

Above-ground tanks:

  • Level, stable foundation required
  • Near rainwater collection points
  • Accessible for filling and distribution
  • Adequate drainage away from foundation
  • Adequate clearance for maintenance
  • Consider visual impact

Ponds:

  • Natural low points or areas easy to dam
  • Clay soils best (or liner required)
  • Adequate watershed to fill pond
  • Not in floodplain or creek channel
  • Soil percolation test if liner questionable
  • Permit requirements met
  • Safe distance from buildings

General site criteria:

  • Gravity flow to irrigation areas if possible
  • Avoid contamination sources
  • Stable ground (no settling or sliding)
  • Access for construction equipment
  • Future expansion potential

Step 4: Design Storage Structure​

Tank/cistern specifications:

  • Material: Polyethylene, fiberglass, concrete, steel
  • Color: Dark colors for UV protection, light colors stay cooler
  • Inlet size: Match to supply pipe
  • Outlet: Bottom drain preferred, multiple heights useful
  • Overflow: 2× inlet size, directed appropriately
  • Vent: Screened to prevent mosquitoes
  • Access hatch: For cleaning and inspection
  • Level indicator: Visual gauge

Foundation for tanks:

  • Gravel pad (compacted)
  • Concrete slab for large tanks
  • Blocking/piers to elevate for gravity flow
  • Account for full weight (8.3 lbs/gallon + tank)

Pond design elements:

  • Dam: If creating reservoir
    • Core: Impermeable clay
    • Shell: Compacted soil
    • Spillway: For overflow management
    • Emergency spillway: For extreme events
  • Liner: If soil too permeable
    • EPDM or PVC rubber (45-60 mil)
    • Underlayment to protect from punctures
    • Anchor in trench around perimeter
  • Depth:
    • Minimum: 4-6 feet to prevent freezing
    • Optimal: 8-12 feet for cool water, less evaporation
    • Shallow shelf: 6-18 inches for habitat
  • Shape:
    • Irregular more natural-looking
    • 3:1 slope for stability and safety
    • Islands for wildlife if large enough
  • Inlet: Diffused to prevent erosion
  • Outlet: Screen to prevent clogging, fish escape

Plumbing system:

  • Pipes sized for flow requirements
  • Valves for control and isolation
  • Filters to protect irrigation system
  • Backflow prevention if needed
  • Drain valves at low points
  • Unions for maintenance access

Step 5: Obtain Permits and Approvals​

Common permit requirements:

  • Water storage over certain size
  • Dams over certain height
  • Work near waterways
  • Grading/excavation permits
  • Building permits for large structures

Agencies to contact:

  • Local building department
  • Water resources board/district
  • Environmental protection agency (wetlands)
  • Army Corps of Engineers (if applicable)
  • County planning department
  • Homeowners association (if applicable)

Documentation needed:

  • Site plan showing structure location
  • Engineering drawings
  • Hydrology report (for dams)
  • Environmental review (NEPA/CEQA)
  • Water rights documentation

Timeline:

  • Small tanks: Often no permit needed
  • Medium structures: 2-6 months
  • Large ponds/dams: 6-18 months
  • Plan early and budget accordingly

Step 6: Construction​

Tank installation:

  1. Prepare level, compacted base
  2. Install foundation (gravel pad or concrete)
  3. Position tank
  4. Connect plumbing
  5. Test system
  6. Secure and protect

Pond construction:

  1. Mark boundaries
  2. Excavate or build dam
  3. Install liner if needed
  4. Create inlet/outlet structures
  5. Test and fill
  6. Establish vegetation

Step 7: Maintain System​

Regular maintenance:

  • Inspect structures regularly
  • Clean filters and screens
  • Check for leaks
  • Maintain overflow systems
  • Monitor water quality
  • Document maintenance

💡 Customization Notes​

When using this template for your project:

  1. Water Needs: Size storage based on your actual water needs

  2. Site Conditions: Adapt design to your site (soil, topography, etc.)

  3. Budget: Choose storage type based on available resources

  4. Legal Context: Research and comply with local regulations

  5. Maintenance: Plan for ongoing maintenance - systems require care

  6. Local Resources: Use local materials, contractors, and expertise

Remember: This is a template. Your actual project will have specific water needs, site conditions, and budget constraints that make it unique.

Next Steps​

Once water storage is built: → Task 4: Efficient Irrigation

Remember: Water storage bridges the gap between when rain falls and when water is needed. Design for your specific needs and site conditions.

This is a template. Customize it for your project.