Water Tanks Northland: Complete Guide to Tank Systems & Water Management

Managing tank water across Northland's diverse landscape - from coastal Whangarei to the remote Far North - requires understanding the unique challenges and opportunities of the region. Whether you're installing your first tank on a new lifestyle block or optimizing an existing system on a Far North farm, this comprehensive guide covers everything Northland property owners need to know.

Understanding Northland's Water Tank Landscape

Northland has one of the highest rates of tank water dependency in New Zealand, with approximately 60% of rural properties relying primarily on rainwater collection and tank storage, according to the Northland Regional Council.

Why Northland Relies on Tanks:

• Limited reticulated water infrastructure outside main centers

• Rural and coastal property locations

• High annual rainfall (but seasonal variations)

• Independence and self-sufficiency values

• Growing population in rural areas

• Lifestyle block popularity

Northland's Rainfall Patterns and Tank Sizing

Regional Rainfall Variations

Northland experiences significant rainfall variation across the region:

Whangarei District:

• Annual average: 1,400-1,600mm

• Wettest: June-August (600-700mm)

• Driest: December-February (200-350mm)

• Summer dry spells: Common

Far North District:

• Annual average: 1,600-2,000mm (east coast higher)

• Wettest: June-August (700-900mm)

• Driest: December-February (250-400mm)

• Microclimates: Significant variation east to west

Kaipara District:

• Annual average: 1,200-1,500mm

• Wettest: June-August (500-600mm)

• Driest: December-February (200-300mm)

• More variable: Western exposure patterns

Calculating Collection Potential in Northland

Formula: Annual Collection = Roof Area (m²) × Rainfall (mm) × Efficiency (0.8)

Example: Whangarei Property

• Roof area: 150 sqm

• Rainfall: 1,500mm

• Collection: 150 × 1.5 × 0.8 = 180,000L/year

• Covers ~70% of 4-person household needs

Example: Far North Property

• Roof area: 200 sqm

• Rainfall: 1,800mm

• Collection: 200 × 1.8 × 0.8 = 288,000L/year

• Covers ~100% of 4-person household needs

The Challenge: Despite high annual rainfall, summer dry periods mean tank storage capacity is critical for year-round supply.

Tank Sizing for Different Northland Properties

Whangarei Urban/Suburban Properties

2-Person Household:

• Minimum: 10,000L (requires frequent deliveries)

• Recommended: 20,000-30,000L

• Optimal: 30,000-40,000L

• Expected deliveries: 4-8 per year

4-Person Household:

• Minimum: 20,000L (high delivery frequency)

• Recommended: 40,000-60,000L

• Optimal: 60,000-80,000L

• Expected deliveries: 3-6 per year

6-Person Household:

• Minimum: 30,000L

• Recommended: 60,000-100,000L

• Optimal: 100,000-120,000L

• Expected deliveries: 2-5 per year

Far North Rural Properties

Considerations:

• Longer delivery times (24-48 hours)

• Higher delivery costs (distance)

• Greater need for self-sufficiency

• Weather-dependent access

Recommended Sizing (30% larger than Whangarei):

• 2-person: 30,000-50,000L minimum

• 4-person: 60,000-100,000L minimum

• 6-person: 100,000-150,000L minimum

Farm Properties:

• Domestic: As above plus

• Stock water: 20,000-50,000L per 50 cattle

• Total: 100,000-200,000L+ typical farm setup

Kaipara District Properties

Similar to Whangarei but consider:

• More variable rainfall

• Some areas more remote

• Access challenges during wet weather

• Size 20% larger than Whangarei minimum

Coastal Kaipara Properties:

• Often more remote

• Salt spray considerations

• Size as per Far North recommendations

Tank Types and Materials for Northland

Plastic/Polyethylene Tanks

Advantages for Northland:

• UV stabilized for Northland sun

• Lightweight (easier installation on remote sites)

• Cost-effective

• Available 2,000L-30,000L

• No rust (coastal areas)

• Easy transport to Far North

Considerations:

• Check UV rating (Northland sun is intense)

• Color matters: Dark colors heat water (algae), light colors better

• Wind resistance: Secure properly (Northland storms)

Cost:

• 10,000L: $1,200-1,800

• 20,000L: $2,200-3,500

• 30,000L: $3,500-5,000

Concrete Tanks

Advantages for Northland:

• Cool water (important in Northland heat)

• Very durable

• Stable in high winds

• No UV degradation

• Long lifespan (50+ years)

Considerations:

• Heavy (challenging Far North installation)

• Higher initial cost

• Require proper foundation

• Limited to accessible sites

Cost:

• 10,000L: $3,500-5,500

• 20,000L: $6,000-9,000

• 30,000L: $9,000-14,000

Steel Tanks

Advantages:

• Large capacity options (50,000-100,000L+)

• Suitable for farms

• Strong and durable

• Available corrugated or stainless

Considerations:

• Rust in coastal Northland (use stainless or well-coated)

• Requires maintenance

• Installation requires crane

• Best for rural properties

Cost:

• 30,000L: $4,000-7,000

• 50,000L: $7,000-12,000

• 100,000L: $15,000-25,000

Installation Considerations Across Northland

Site Selection

Universal Requirements:

• Level ground or proper stand

• Close to house (shorter pipe runs)

• Higher than house if gravity-fed

• Accessible for delivery trucks

Northland-Specific:

• Shade in Whangarei/Far North summer heat

• Wind protection (especially coastal)

• Away from large trees (leaf debris, root damage)

• Flood-free location (some Northland areas prone)

• Access despite wet weather (Far North, Kaipara rural roads)

Foundation Requirements

Small Tanks (up to 10,000L):

• Compacted gravel base

• Level concrete pad (optional but recommended)

• Minimum cost: $200-500

Medium Tanks (10,000-30,000L):

• Reinforced concrete pad essential

• Proper drainage

• Engineering for stability

• Cost: $800-2,000

Large Tanks (30,000L+):

• Engineered concrete pad

• Geotechnical assessment may be needed

• Consider Northland soil conditions

• Cost: $2,000-5,000+

Access for Installation

Whangarei Urban:

• Usually good truck access

• Crane available if needed

• Standard installation

Far North/Remote:

• Verify access before ordering

• May need smaller tanks (transport limits)

• Crane availability limited

• Consider helicopter delivery for very remote ($$$)

Catchment Optimization for Northland

Roof Catchment Areas

Maximize Collection:

• Connect all roofs (house, garage, sheds)

• Calculate total catchment area

• Install proper guttering throughout

Example: Far North Lifestyle Block

• Main house: 180 sqm

• Garage: 60 sqm

• Garden shed: 30 sqm

• Barn: 100 sqm

• Total: 370 sqm

• At 1,800mm rainfall: 532,800L potential

• Exceeds typical household needs!

Guttering for Northland Conditions

Sizing:

• Minimum: 150mm wide gutters

• Recommended: 175mm for Northland's intense rainfall

• Downpipes: 100mm minimum

Leaf Guard Essential:

• Pohutukawa, kauri, native trees

• Coastal debris

• High bird activity

• Options: $15-60 per metre

Maintenance Schedule:

• Quarterly cleaning minimum

• After storms

• Before winter (maximize collection)

• Post-summer (clear dry debris)

First Flush Systems for Northland

Why Essential in Northland:

• Long dry summers = roof contamination buildup

• Dust from rural areas

• Salt spray in coastal areas

• Bird droppings

• Insect debris

System Types

Basic Pipe Diverter ($100-200):

• Suitable for small roofs

• Manual emptying

• Good for single downpipe

Ball Valve System ($200-400):

• Automatic operation

• Self-draining

• Better for multiple downpipes

Professional System ($400-800):

• Best for Northland conditions

• Handles intense rain

• Multiple catchment capability

Recommended Diversion Volume:

• Northland standard: 25L per 50 sqm roof

• Coastal: 30L per 50 sqm (salt spray)

• After long dry period: First significant rain = manual diversion

Water Quality in Northland Tanks

Testing and Treatment

When to Test:

• New tank installation

• After long dry period

• If taste/odor changes

• Annually recommended

• If health concerns

Testing Options:

Home Test Kit ($40-80):

• pH, chlorine, basic bacteria

• Quick results

• Good for routine checks

Laboratory Testing ($150-350):

• Comprehensive analysis

• E. coli, bacteria, chemicals

• Definitive results

• Use NRC-approved labs

Common Northland Issues

Tannin Staining:

• Source: Kauri, native trees

• Effect: Brown tint (safe but unappealing)

• Solution: Filtration, more first flush diversion

Algae Growth:

• Source: Light + nutrients

• Prevention: Dark tanks, covered, clean

• Treatment: Shock chlorination if severe

Salt Contamination:

• Coastal properties

• Storm surge spray

• Regular gutter cleaning essential

Tank Maintenance Across Northland

Cleaning Schedule

Whangarei Urban:

• Professional cleaning: Every 2-3 years

• Cost: $250-400

• Quick access for services

Far North/Remote:

• Professional cleaning: Every 2-3 years but plan ahead

• Cost: $350-600 (includes travel)

• May need to DIY due to access

• Book during dry season

DIY Cleaning:

• Save $200-300

• Requires safety equipment

• Confined space risks

• Time: 4-8 hours

• Best in summer/autumn

Inspection Schedule

Monthly (5 minutes):

• Check tank level

• Inspect for leaks

• Check overflow working

• Look for damage

Quarterly (30 minutes):

• Clean gutters

• Check first flush

• Inspect roof

• Clear vegetation near tank

• Check pump operation

Annual (2-3 hours):

• Detailed inspection

• Professional pump service

• Check all connections

• Consider water quality test

• Plan any upgrades

Pump Systems for Northland

Pump Selection

Household Requirements:

• Minimum: 35-45 PSI

• Comfortable: 45-55 PSI

• Optimal: 50-60 PSI

• Flow rate: 15-25 L/min minimum

Pump Types:

Surface Pumps ($300-800):

• Suitable for smaller homes

• Easy maintenance

• Noisier

• Good for Whangarei urban

Submersible Pumps ($800-1,500):

• Better for larger properties

• Quieter

• More reliable

• Ideal for Far North farms

Pressure Pumps ($600-1,200):

• Automatic control

• Consistent pressure

• Best user experience

• Recommended for all new installs

Solar Power Considerations

Advantages in Northland:

• Abundant sunshine

• Reduces power costs

• Good for remote properties

• Environmental benefits

System Cost:

• Basic solar + pump: $2,000-4,000

• Medium system: $4,000-8,000

• Large property: $8,000-15,000

Best For:

• Far North remote properties

• Off-grid lifestyle blocks

• Reducing running costs

• Environmental focus

Multiple Tank Strategies

Series Configuration

Method: Tanks connected, first fills then overflows to second

Advantages:

• Simple

• Maximizes first tank collection

• Good for sequential installation

Best For:

• Gradual expansion

• Budget-conscious approach

Parallel Configuration

Method: Both tanks fill simultaneously from same source

Advantages:

• Even distribution

• Better for different tank types

• More complex but flexible

Best For:

• Planned systems

• Large properties

• Commercial/farm use

Dedicated Purpose Tanks

Strategy: Separate tanks for different uses

Example: Northland Farm

• Tank 1: 50,000L domestic (best quality)

• Tank 2: 30,000L garden/washing (lower quality OK)

• Tank 3: 50,000L stock water (separate system)

Advantages:

• Prioritize water quality

• Optimize maintenance

• Backup if one system fails

Regional Water Delivery Integration

Whangarei District

Strategy:

• Size tanks for 80% rainfall collection

• Accept 4-6 deliveries/year

• Delivery cost: $1,200-2,000/year

• Fast response: 2-5 days

• Competitive pricing

Recommended:

• 60,000L for family of 4

• Monitor at 40%

• Book delivery at 35%

Far North District

Strategy:

• Size tanks for 90% rainfall collection

• Accept 2-4 deliveries/year

• Delivery cost: $1,500-2,500/year

• Slower response: 1-2 weeks

• Higher costs (distance)

Recommended:

• 80,000-100,000L for family of 4

• Monitor at 50%

• Book delivery at 45%

• Maintain relationships with multiple carriers

Kaipara District

Strategy:

• Size tanks for 85% rainfall collection

• Accept 3-5 deliveries/year

• Delivery cost: $1,300-2,200/year

• Variable response depending on location

Recommended:

• 70,000L for family of 4

• Monitor at 45%

• Confirm carrier services your area

Cost Analysis: Tank Investment vs. Delivery Costs

Example: Whangarei 4-Person Household

Option A: Small Tank (20,000L)

• Tank cost: $2,500

• Installation: $500

• Total: $3,000

• Annual deliveries: 12 × $320 = $3,840

• Total Year 1: $6,840

• Annual ongoing: $3,840

Option B: Optimal Tank (60,000L)

• Tank cost: $8,000

• Installation: $1,500

• Total: $9,500

• Annual deliveries: 5 × $320 = $1,600

• Total Year 1: $11,100

• Annual ongoing: $1,600

ROI Analysis:

• Extra investment: $5,500

• Annual savings: $2,240

• Payback: 2.5 years

• 10-year savings: $22,400

• 20-year savings: $44,800

Winner: Larger tank by far!

Example: Far North Farm

Option A: Minimal (60,000L)

• Tank cost: $8,000

• Installation: $2,000

• Total: $10,000

• Annual deliveries: 8 × $550 = $4,400

• Total Year 1: $14,400

• Annual ongoing: $4,400

Option B: Optimal (120,000L)

• Tank cost: $20,000

• Installation: $4,000

• Total: $24,000

• Annual deliveries: 3 × $550 = $1,650

• Total Year 1: $25,650

• Annual ongoing: $1,650

ROI Analysis:

• Extra investment: $14,000

• Annual savings: $2,750

• Payback: 5.1 years

• 10-year savings: $27,500

• 20-year savings: $55,000

• Plus: Reduced stress, better self-sufficiency

Regulations and Consents in Northland

Building Consent Requirements

When Required:

• Tanks over 35,000L capacity

• Structural installations

• Earthworks for large tanks

• Commercial installations

District-Specific:

Whangarei District Council:

• Building Consents

• Standard process

• Fees: $200-500 for tank consent

Far North District Council:

• Similar requirements

• May be more flexible for rural properties

• Contact: fndc.govt.nz

Kaipara District Council:

• Rural-focused approach

• Check specific requirements

• Contact: kaipara.govt.nz

Plumbing Requirements

Licensed Plumber Required:

• Connection to household plumbing

• Backflow prevention

• Compliance certificate

• Cost: $500-1,500 depending on complexity

Resource Consents

Usually Not Required:

• Rainwater collection

• Domestic-scale tanks

• Standard installations

May Be Required:

• Very large commercial systems

• Significant earthworks

• Coastal hazard zones

• Check with Northland Regional Council

Seasonal Management in Northland

Summer Strategy (December-February)

Tank Management:

• Monitor twice weekly

• Maximum conservation

• Book deliveries at 40% (Whangarei) or 50% (Far North)

• Expect 2-4 deliveries this season

Actions:

• Install shade cloth if tank exposed

• Check for leaks (expensive in summer)

• Clear gutters before any rain

• Have carrier contact details ready

Autumn Approach (March-May)

Tank Management:

• Relax monitoring to weekly

• Moderate conservation

• Catch rainfall to refill

• Book one fill if needed

Actions:

• Deep clean gutters

• Service pump

• Inspect roof

• Plan any upgrades

• Prepare for winter collection

Winter Collection (June-August)

Tank Management:

• Minimal monitoring

• Normal water use

• Abundant rainfall

• Tanks should fill naturally

Actions:

• Enjoy savings period!

• Catch up on maintenance

• Professional tank cleaning

• Plan summer preparations

Spring Preparation (September-November)

Tank Management:

• Resume weekly monitoring

• Start conservation mindset

• Consider pre-emptive fill

• Prepare for summer

Actions:

• Check all systems functioning

• Repair any issues

• Test first flush

• Book early summer fill if tank not 100%

Technology for Northland Tank Management

Smart Monitoring Systems

Benefits:

• Real-time levels via smartphone

• Alerts at custom thresholds

• Usage tracking

• "Days remaining" calculations

• Historical data

Recommended Systems:

For Whangarei (WiFi available):

• Tank Utility: $399

• WiFi-based

• Good app

• Alert at 40%, 30%, 20%

For Far North (Remote):

• GSM Monitor: $550

• Cellular connectivity

• Works anywhere

• Critical for long delivery lead times

• Alert at 50%, 40%, 30%

ROI: One avoided emergency delivery ($150-300 premium saved) + better planning = system pays for itself in 1-2 years.

Weather Integration

Advanced Systems:

• Link to local weather forecasts

• Adjust "days remaining" based on forecast rain

• Delay delivery requests if significant rain predicted

• Useful for Northland's variable patterns

Water Conservation for Northland Properties

Bathroom Savings

Low-Flow Showerheads:

• Cost: $60-150

• Savings: 40,000-60,000L/year (family of 4)

• Payback: <1 year in avoided deliveries

Shorter Showers:

• Target: 5 minutes

• Use timer or music

• Savings: 50,000L/year for family of 4

Dual-Flush Toilets:

• Cost: $250-450

• Savings: 25,000L/year

• Payback: 1-2 years

Garden Strategies for Northland

Drought-Tolerant Natives:

• Pohutukawa

• Coprosma

• Pittosporum

• Flax (Phormium)

• Carex species

Water-Wise Practices:

• Mulch heavily (7-10cm)

• Water early morning or evening

• Deep watering less often

• Drip irrigation

• Group plants by water needs

Savings: Reduce garden water by 50-70%

Collecting Greywater

Legal in Northland: Greywater reuse allowed with restrictions

Sources:

• Bathroom sinks

• Showers

• Washing machine

Uses:

• Garden watering (not vegetables)

• Ornamental plants

• Lawn

System Cost:

• Simple: $200-500

• Professional: $2,000-5,000

Emergency Backup Strategies

Bore Water

Northland Bore Viability:

• Variable by location

• Generally good in coastal areas

• Check with NRC for requirements

• Consent required

Cost:

• Drilling: $8,000-15,000

• Pump and equipment: $3,000-6,000

• Total: $11,000-21,000

Advantages:

• Backup for summer

• Reduces delivery dependency

• Good for farms

• Can supply garden/stock separate from drinking water

Reciprocal Arrangements

Community Strategy:

• Neighboring properties with excess capacity

• Mutual assistance agreements

• Especially valuable Far North/remote

• Reduces emergency delivery needs

Emergency Water Storage

Strategy: Small emergency reserve separate from main tank

Example:

• Main: 60,000L household tank

• Emergency: 2,000L separate storage

• Filled when main at 100%

• Untouched unless emergency

• Gives 4-5 days buffer

Future-Proofing Northland Tank Systems

Climate Change Considerations

Northland Projections (2025-2050):

• More intense rainfall events (good for collection)

• Longer dry periods between rain (harder on tanks)

• Hotter summers (more evaporation, higher use)

• More variable patterns (harder to predict)

Adaptation Strategies:

• Increase storage capacity

• Better monitoring systems

• Enhanced conservation

• Multiple water sources

• Community water sharing

Expansion Planning

Start Medium, Plan Large:

• Install 60,000L tank now

• Prepare site for second tank

• Add second tank later (80,000L)

• Total: 140,000L system

• Lower initial cost, good final capacity

Choosing Tank Suppliers and Installers in Northland

Questions to Ask Suppliers

Essential Questions:

• Tank warranty period?

• UV rating suitable for Northland?

• Installation included or extra?

• Delivery cost to your location?

• Lead time for your size?

• After-sales support?

Installation Considerations

Get Multiple Quotes:

• Tank supply and delivery

• Site preparation

• Installation

• Plumbing connection

• Pump and electrics

• Total turnkey price

For Far North:

• Confirm installer serves your area

• Understand travel costs

• Lead time may be longer

• Consider local installers for ongoing support

Working with Water Carriers

When You Need Water Delivery Northland Services:

Whangarei Region: Gracies Cartage provides reliable water delivery Northland services:

• Phone: 0800 42 2278

• Mobile: 021 279 6757

• Website: graciescartage.co.nz

• Regular and emergency delivery

• Health board approved water

Building Relationships:

• Pay promptly

• Maintain clear access

• Provide accurate tank information

• Book in advance when possible

• Regular customers get priority

Conclusion: Thriving with Water Tanks Northland

Water tanks Northland properties rely on represent both challenge and opportunity - the challenge of managing supply through summer dry periods, and the opportunity for self-sufficiency and connection to natural water cycles.

Key Success Factors:

✓ Right-size from the start - Larger is almost always better ✓ Maximize catchment - Connect every roof surface ✓ Monitor actively - Smart systems worth investment ✓ Maintain regularly - Prevention cheaper than emergency ✓ Conserve wisely - Especially in summer ✓ Plan by region - Far North needs more capacity ✓ Build relationships - With water carriers for when you need them ✓ Think long-term - Upfront investment pays off over decades

Regional Approach:

• Whangarei: 60,000L+, monitor at 40%, fast delivery available

• Far North: 80,000L+, monitor at 50%, plan ahead for delivery

• Kaipara: 70,000L+, monitor at 45%, confirm carrier availability

With proper planning, adequate capacity, and smart management, water tanks Northland properties depend on can provide reliable, cost-effective, and environmentally sustainable water supply for generations.

For water delivery Northland services when your tank needs refilling, contact Gracies Cartage at 0800 42 2278.

For regional water management information, visit Northland Regional Council.

Last updated: October 2025