Feasibility study @ Walmart to become ‘Net Water Positive’

As a Total Water Management company our aim was to decrease freshwater buy for Walmart and to create 150% water positive footprints (the amount of water reused/recharge is 1.5 times of demand) through our standardized analytical approach. The reduction in intake of fresh water will be economically beneficial for the client, fulfill all the regulatory requirements & a positive step towards environmental sustainability.

Wapp’s Solution: Total Water Management
Total Water Management (TWM) is an approach based on a holistic view of the water resources system and principles of sustainability. TWM can be utilized to increase water resources efficiently and enhance overall benefits. It examines water systems in a more interconnected manner, focusing on reducing water demands for fresh water, increasing water recycling and reuse and creating water supply assets from rainwater. The major components of TWM applied to achieve net water positive at Walmart Ludhiana –
1. Weather Mapping (for variation in temperature, humidity & rainfall for calculating the seasonal variation of water consumption in horticulture, cooling tower & rainwater storage/recharge)
2. Architectural Mapping (for variation in horticulture water demand & rainwater potential)
3. Water Mapping (for quantity & quality of water, water sourcing for different usage through benchmarking data)
4. Water Conservation Technique (Rainwater harvesting, AC condensate recovery, Demand-side management, horticulture techniques to conserve water & Cooling tower management to decrease blowdown)
5. Real-Time Monitoring (Water IoT, Weather Station & water quality alerts)

The fresh Water Consumption in a building is given as –

Fresh Water Consumption = Cooling Tower Evaporation+ Horticulture+ Apparent Losses+ Hidden Losses+ Excess Water.
Results

a) The total Water consumption decreases significant ally from 25352 ltrs to 13307 ltrs.
b) Total Wastewater generation based on consumption would be 6850 liters/day.
c) The freshwater demand would decrease from 6456.95 liters to 5996.95 liters/day.
d) Total Rainwater Harvesting Potential would be 9010.412 liters/day (as per seasonal variation & average.)
e) As per the current Walmart Ludhiana site, the store is air cooled which will produce a considerable amount of condensate water. The condensate can be collected and reused. As per our experience, seasonal variation & data available the current system at Walmart Ludhiana can produce about 460 liters of water per day on an average yearly basis.
f) Hence, the Total water positive footprint would climb up to 150.25%.