The cannabis industry is booming. Increased awareness of cannabidiol (CBD) products in particular has led to a lucrative market with high demands.
While sourcing good quality cannabis in Europe can still be a challenge, more and more European countries are easing cannabis restrictions and conducting research into the benefits of this plant as a medical supplement.
But the proliferation of cannabis farming to meet this increased demand can come at a cost — an environmental one.
The cannabis industry is particularly susceptible to the impact of water shortages and drought. Plus, the environmental effects of unsustainable grow operations can put heavy pressure on the local environment — causing permanent damage to the natural resources available.
And this is bad news, not just for the earth, but for business as well.
This article will take a look at the environmental impacts of cannabis cultivation, especially in terms of water consumption. Further, it will also go over some exciting new developments in cannabis cultivation technology, highlighting companies that offer innovative approaches to improving water usage in cannabis farming.
Environmental impacts of cannabis
With cannabis cultivation and distribution becoming legal in the United States and much of Europe, the industry is truly on the rise. Demands for CBD have increased dramatically in the last three years, with the market for CBD expected to increase to almost $2 billion by 2022.
As the market balloons, growers must adapt to the heavier pressures caused by an increased demand for product. Environmental concerns can easily get lost in that constant pressure, but it is vital — and not difficult — to set up a more sustainable infrastructure within each grow operation.
First, let’s investigate the causes and effects of water waste in cannabis cultivation.
For an indoor cannabis production at any scale, water is sourced, usually from a municipal water supply, and then processed through a filtration system and used for cooling and dehumidification. Operations without sustainable tools generate huge amounts of water and energy waste during the filtration process alone, with saline byproducts typically being directly disposed of and not repurposed.
Next, the filtered water is stored in a reservoir or fertigation system, which is then pumped into an irrigation system that waters the plants. The runoff from this stage of the process also flows directly into waste disposal, resulting in a huge water footprint from wasted and unusable water resources.
In areas with arid climates where water shortage is a top-priority concern, this is a huge detriment to companies with long-term goals — and a big problem in terms of the environment.
Luckily, there are a host of innovative approaches to bettering water consumption methods in the cannabis industry.
New tech solutions for cannabis watering
Rather than wasting water during the filtration process, some companies have turned to processes of water reclamation, through which they capture and recycle wastewater that would be headed straight for the sewage drain. The water can be re-filtered and re-used, contributing to a significant cut in wastewater production and lowering a cannabis cultivator’s overall demand for water resources, as well as reducing operational costs.
Various water reclamation strategies can be employed to make the best use of this precious resource. One of the promising options out there seems to be the Automated Reclaimed Condensate System produced by Hydrologic.
Hydrologic was awarded the 2019 Cannabis & Tech Today Sustainable Leadership Award for Water Usage for this system, which allows companies to automatically reclaim up to 80 percent of their irrigation water volume.
The Automated Reclaimed Condensate System, or ARCS, is designed to reduce water demand by claiming and repurposing HVAC condensate runoff — a natural fit for cannabis cultivation, which necessitates a tightly controlled temperature in the growing environment.
The system also automatically filters the repurposed water, removing heavy metals and biological waste, and balancing the water’s pH for ideal cannabis growth conditions. Hydrologic has stated that its ultimate goal is to create a large-scale zero wastewater production facility and then spread that model, reducing the general wastewater percentage to nothing.
While Hydrologic offers one of the most popular technologies for water reclamation, other small operations are following suit, employing various tools to collect condensate from air conditioning and dehumidification units.
Harvest Foundation, for example, relies on reclaimed runoff water for one-half to two-thirds of its water use, while Garden Remedies uses a custom reverse osmosis system to filter its HVAC runoff water.
Meanwhile, Sense, a cannabis cultivator with a 2,000-sq-ft grow in San Francisco, has converted its operation so that it now runs off of 100 percent renewable energy, thus dramatically reducing its ecological impact.
In addition to powering a grow using modern sustainable technologies like solar and wind energy, it is important to look at best usages of limited resources, like water. Irrigation is the most obvious direct use of water in any grow, and while it may seem like irrigation methods are limited, there are actually many options to choose from.
Besides the standard surface, drip and overhead irrigation methods, cannabis cultivators can now utilise sprinkling irrigation systems, mist irrigation, sub-irrigation, intra-soil irrigation and aquaponics.
Green Relief, in Ontario, Canada, is the first licensed cannabis grower in North America to adopt a commercial-scale aquaponics system. This sustainable closed-system technology utilises fish faeces to fertilise the water in which plants will grow.
The waste from the fish circulates through the root systems of the plants, allowing them to absorb extra nutrients, while the plants serve as a natural filtration system to keep the fish habitat clean. Drawing on this natural symbiotic relationship, aquaponics, when done correctly, presents a zero waste, renewable, sustainable option for growing cannabis.
Old ideas, new uses
Strategies like purifying reclaimed wastewater and reaping the benefit of natural symbiotic relationships, as in aquaponics systems, have been around for a long time. The same aquaponics style of farming has been used in traditional rice paddy cultivation as well as by ancient Aztec people.
Now, though, cutting edge technological innovations allow us to maximise these traditional approaches to farming, utilising them in large, commercial-scale contexts.
As global warming and ecological catastrophe loom large, steering the flourishing cannabis industry towards sustainable practices is essential, so that the environment and the plants can both continue to grow.