24/04/2025

Zero Net Water: What We Must Do

Introduction

We all learned early in school that 75% of our planet is covered in water, while only 25% is land. But here's the catch—97% of that water is salty and found in oceans. Only 3% is freshwater, and even then, two-thirds of it is locked away in glaciers. That leaves us with just 1% of accessible freshwater for all of humanity. Water isn’t just abundant—it’s essential. It regulates the Earth’s temperature and sustains every living being through a natural process we know as the water cycle.

The Water Crisis at Our Doorstep

Despite this divine arrangement, our current way of life and rapid urbanization are disturbing the water cycle:

Cities like Dhaka’s Uttara are covered in concrete and asphalt, leaving no room for rainwater to seep into the ground.
Impervious surfaces prevent groundwater recharge.
Over-extraction of groundwater has become alarmingly unsustainable.

In 1970, groundwater was found at 6 meters in Dhaka. By 2025, it has dropped to 75 meters—and is projected to reach 120 meters by 2050.

Meanwhile, climate change is melting glaciers, raising sea levels, and causing saltwater intrusion in coastal regions—putting the freshwater supply of 40 million Bangladeshis at risk.

What Is Net Zero Water?

Net Zero Water means balancing water consumption with local water availability and returning used water safely back to the environment. To achieve this, we must reduce dependence on groundwater and prioritize surface water and rainwater through smart design, policies, and daily habits.

What We Can Do—A Multi-Level Approach

✅ Government-Level Actions

Implement and enforce the Net Zero Water concept.
Protect rivers and water bodies.
Resolve international river water disputes (especially with India).
Introduce more water-related content in education.
Promote water-focused research and development.

✅ Personal-Level Actions

Avoid water wastage—make it a lifestyle.
Use modern, water-efficient fixtures, like:
Sensor-based taps
- Dual-flush toilets
- Smart meters

“Eat and drink, but do not waste.Surely, He does not like the wasteful.” (Qur’an, Surah Al-A’raf 7:31)

✅ Community & Organizational Roles

Don’t use potable water for all tasks (e.g., car washing, gardening).
Use rainwater harvesting systems and treat lake water for non-drinking uses.
Utilize greywater (non-toilet wastewater) for gardening or cleaning.
Set up centralized car wash stations to reduce waste.
Develop a city hydrant system using lake water for fire safety.

Uttara Case Study – Rainwater Potential

Uttara’s population: 250,000
Water need: 180 liters/person/day = 45 million liters/day
Rainwater potential:
- Uttara’s area: 2,500 acres
- Avg. rainfall: 85mm/hour
- Rainwater catchment: 8 million m³/hour

Just one hour of rainfall can supply enough water for 15 days!

This opens the door for a local blue economy, with potential for clean water entrepreneurship and sustainable community practices.

Conclusion

Water is life—and our actions today will determine our tomorrow. Let us join hands in embracing the Zero Net Water movement, conserve our resources, and protect future generations.

Md. Shahjahan Alam

BSc in Mechanical Engineering (BUET)

MSc in Environmental Science, MBA

Fellow – IEB, LEED Green Associate

Chairman – Axis Triangle Group, Uttara, Dhaka, Bangladesh