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Task 1: Assess Water Needs - 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​

Understanding your site's water needs and availability is the foundation of effective water management. This assessment reveals the gap between natural water supply and plant requirements, identifies opportunities for water harvesting and conservation, and guides decisions about irrigation, storage, and drought preparedness.

This is a template. Customize assessment methods, data sources, and calculations based on your specific climate, site conditions, and water availability.

🎯 Non-Negotiables (Science Consensus)​

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

  1. Water Assessment Required: Before designing water systems, you must assess water needs, availability, and patterns. You cannot manage what you don't understand.

  2. Match Plants to Water: Plant selection must match available water. Planting water-demanding species in arid conditions without adequate water supply will fail.

  3. Water Budget Required: A water budget (supply vs. demand) must be calculated. This is essential for sustainable water management.

  4. Climate Data: Historical precipitation and climate data must be used in assessment. Current year data alone is insufficient.

  5. Documentation: All water assessment data, calculations, and assumptions must be documented. This is essential for adaptive management.

🔀 Options & Pathways​

Pathway A: Professional Hydrological Assessment​

When to use: Complex sites, when water is critical limiting factor, larger projects, grant requirements

Approach:

  • Hire professional hydrologist or water resources specialist
  • Comprehensive water budget analysis
  • Climate data analysis and projections
  • Site-specific measurements
  • Professional recommendations

Pros:

  • Most thorough and accurate
  • Professional validation
  • Credible for grants
  • Comprehensive analysis

Cons:

  • Higher cost (€1,000-5,000)
  • Requires professional expertise
  • May take longer

Pathway B: Extension Service Assessment​

When to use: Standard projects, moderate budget, want professional guidance at lower cost

Approach:

  • Use university extension service or government resources
  • Standard water budget calculations
  • Extension interpretation and recommendations
  • Use available climate data
  • DIY site measurements with expert review

Pros:

  • Lower cost (€100-500)
  • Professional guidance
  • Extension support
  • Good balance

Cons:

  • Less comprehensive
  • Standard approaches only
  • May need additional analysis

Pathway C: DIY Assessment with Expert Review​

When to use: Limited budget, want to learn, have access to basic tools

Approach:

  • Research climate data online
  • Basic water budget calculations
  • Simple field measurements
  • Expert review of results
  • Community science approaches

Pros:

  • Lowest cost (€0-200)
  • Educational value
  • Hands-on learning
  • Accessible

Cons:

  • Less accurate
  • May miss issues
  • Requires learning
  • May need validation

Pathway D: Hybrid Approach​

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

Approach:

  • Professional assessment for critical aspects
  • DIY for basic calculations
  • Expert consultation as needed
  • Mix of professional and field methods

Pros:

  • Good balance
  • Cost-effective
  • Flexible
  • Professional validation

Cons:

  • Requires coordination
  • May need ongoing consultation

📋 Implementation Steps​

Step 1: Research Climate and Precipitation Data​

Gather historical precipitation data:

  • Average annual rainfall for your location
  • Monthly distribution of rainfall (seasonal patterns)
  • Rainfall variability (drought vs. wet years)
  • Snow accumulation if applicable
  • Recent trends (last 10-20 years)
  • Climate change projections for your region

Data sources:

  • National weather services
  • State climatology offices
  • Local weather stations
  • Agricultural extension services
  • Online climate databases

Key metrics to collect:

  • Average annual precipitation (inches or mm)
  • Wettest and driest months
  • Number of rain days per year
  • Intensity patterns (gentle rains vs. downpours)
  • Frost-free growing season length
  • Humidity levels

Step 2: Calculate Evapotranspiration (ET)​

What is ET:

  • Water lost through plant transpiration + soil evaporation
  • Critical for understanding how much water plants actually need
  • Varies by temperature, humidity, wind, and plant type

How to calculate:

  • Use reference ET (ETo) data from weather stations or services
  • Multiply ETo by crop coefficient for your vegetation type
  • Account for seasonal variation

Find ETo data:

  • Weather station networks
  • Extension service calculators
  • Online ET calculators
  • Climate databases

Crop coefficients (Kc):

  • Native grassland: 0.6-0.8
  • Forest/woodland: 0.8-1.0
  • Agricultural crops: 0.3-1.2 depending on type
  • Newly planted areas: 0.5-0.7 during establishment

Step 3: Assess Soil Water-Holding Capacity​

Why it matters:

  • Soil acts as water storage between rain events
  • Different soils hold vastly different amounts
  • Determines irrigation frequency and drought vulnerability

How to assess:

  • Use soil texture to estimate capacity
  • Test infiltration rate
  • Measure field capacity
  • Consider organic matter content (increases capacity)

Soil water-holding capacity (approximate):

  • Sand: 0.5-1.0 inches per foot
  • Loam: 1.5-2.5 inches per foot
  • Clay: 2.0-3.0 inches per foot
  • Organic matter: Each 1% adds ~0.2 inches per foot

Step 4: Determine Plant Water Requirements​

Factors affecting requirements:

  • Species type (drought-tolerant vs. water-demanding)
  • Plant age (establishment vs. mature)
  • Season (growing season vs. dormant)
  • Climate (temperature, humidity, wind)

Calculate for your target vegetation:

  • Research water needs for each species
  • Account for establishment period (higher needs)
  • Consider seasonal variation
  • Plan for mature vs. establishment needs

Step 5: Create Water Budget​

Water Budget = Supply - Demand

Supply (Inputs):

  • Annual precipitation
  • Runoff capture potential
  • Groundwater (if accessible)
  • Surface water (streams, springs)
  • Imported water (if available)

Demand (Outputs):

  • Plant evapotranspiration
  • Soil evaporation
  • Deep percolation
  • Runoff (unavoidable)
  • Other uses

Calculate gap:

  • If Supply > Demand: Water is adequate
  • If Supply < Demand: Need to increase supply or reduce demand

Plan for variability:

  • Drought year scenario
  • Wet year scenario
  • Seasonal variations

Step 6: Identify Water Management Needs​

Based on water budget, determine:

  • Do you need irrigation? (If yes, how much?)
  • Do you need water storage? (If yes, how much?)
  • Do you need water harvesting? (If yes, what type?)
  • Can you work within natural water budget? (If yes, select appropriate species)

Prioritize strategies:

  • Most critical needs first
  • Most cost-effective approaches
  • Long-term sustainability
  • Integration with other restoration activities

💡 Customization Notes​

When using this template for your project:

  1. Climate: Adapt methods to your specific climate (arid, Mediterranean, humid, etc.)

  2. Data Sources: Use local climate data sources available in your region

  3. Site Conditions: Factor in your specific site conditions (topography, soil, etc.)

  4. Species Selection: Match plant water needs to available water

  5. Budget: Choose assessment pathway based on available resources

  6. Local Resources: Use local extension services, weather stations, and experts

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

Next Steps​

Once water needs are assessed: → Task 2: Rainwater Harvesting

Remember: You cannot manage what you don't understand. A thorough water assessment is the foundation of sustainable water management.

This is a template. Customize it for your project.