Marijuana cultivation is, at its core, an agricultural endeavor, requiring large amounts of energy and water to nurture and grow the raw product. Through this series of blog posts, I have considered some of the environmental regulatory issues that may arise with respect to this growing industry. But what about the environmental impacts of marijuana cultivation? This blog post will explore – in general terms – some of the known environmental impacts of the recreational marijuana industry, drawing from the lessons learned in the states that have led the way.
There is no way around it: marijuana is a plant, and plants need water to grow and thrive. Whether a cultivator operates an indoor or outdoor grow operation, the data is clear that water consumption is high in the industry. By some estimates, plants grown outdoors require at least one gallon per pound of marijuana per day during the growing season, which amounts to a total of roughly 150 gallons of water per pound of weed. For marijuana grown in an indoor setting, the rate of consumption is much, much higher. In California, for example, indoor growers estimate that they use as much as 450 gallons of water per pound of marijuana grown. While those numbers compare favorably to other crops commonly grown in New York and New Jersey – such as strawberries and tomatoes – it is still anticipated that the recreational marijuana industry will make new, appreciable demands on local water supply systems. Accordingly, water utilities and market entrants alike can be expected to pay significant attention to a proposed cultivator’s expected water use and the local water system’s firm capacity to ensure proper siting.
Energy Use and Carbon Footprint
Based on current New Jersey’s medical cannabis cultivation trends, we can anticipate that much of the recreational cannabis cultivated in New Jersey and New York will be grown entirely indoors. That method can provide cultivators with a minute level of control over their growing environments, but it comes at a cost. Marijuana plants need a lot of sunlight to thrive, meaning that indoor growing options must resort to intense artificial light to replicate sunshine, as well as sophisticated environmental control systems, which promote adequate air circulation, temperature and humidity control, and ensure appropriate carbon-dioxide levels to accelerate plant growth. These systems generally require significant amounts of electricity or natural gas to operate. Given the prevalence of fossil-fuel-based electric generation, this leads to a large carbon footprint. Moreover, the introduction of additional carbon dioxide to promote photosynthesis accounts for as much as 25% of the carbon emissions from indoor operations, further enlarging the industry’s carbon footprint. That said, New York and New Jersey produce significant levels of electricity from renewable sources, with both states having committed to expanding those levels over time. In addition, the industry writ large is aware of its carbon footprint and has begun exploring the use of LED grow lights and other, more ecologically conscious means of environmental control. Given that, by some estimates, the energy costs of environmental control systems can account for roughly 60% of the cannabis industry’s carbon footprint, there is significant room for progress in that regard.
While it may be surprising to some, marijuana cultivation – if not done carefully – can create negative environmental impacts. Many of these impacts are likely to be addressed as New York and New Jersey create the rules governing this new industry. Nevertheless, it is important to learn from those who went before us and work toward growing a sustainable industry, to the extent feasible, from the ground up.