Tag Archives: well

November 8, 2022

The 3-Legged Stool of Successful Grow Operations: Climate, Cultivation & Genetics – Part 2

By Phil Gibson

This is Part 2 in The 3-Legged Stool of Successful Grow Operations series. Click here to read Part 1 and stay tuned for Part 3 coming next week.

Aeroponic and hydroponic systems use zero-soil, so water is effectively our media and our transport mechanism for nutrition. Ideally, you start with clean, fresh water with “nothing” in it. Nothing in this case means no heavy metals, pesticides, bacteria or pathogens. There are some scary words in there so let’s talk through the best ways to get to “nothing.”

The first place to start is by testing your source water, whether it is surface, well or municipal water. This will give you an initial idea of how “empty” your water is. Water supplies shift over time, so it is also a very important input to monitor over time with annual or bi-annual testing. Clean water is the essence of success for aeroponics and a great way to lower your cost of production. With proper design and management, you can recycle and reuse 95%+ of the water you draw into your facility.

Reverse Osmosis (RO)

RO is the most common way to clear your incoming water. The process uses pressure filtration by forcing your water through a series of filters or meshes that block or extract large particles, organics and metals. Normally this is 98%-99% efficient. These systems do require attention and maintenance as they do have filters that are required to be changed regularly depending on the clarity of your original water source and the type of material filtered. This accomplishes a lot of your water clearing process to empty the balloon, but it does not clear the pesky biologicals or pathogens. RO is covered in detail in our “You are what you drink” webinar so look that over for a deeper explanation. There are a wide range of relatively low-cost suppliers based on capacity and filtration efficiency. From an operations standpoint, the key is to understand the filter replacement cycle and cost of replacement.

Ultraviolet Light (UV)

UV light can be used to clear organics and pathogens from water. The primary use is to clear origin water but it is also especially important for recovered water that you save from the humidity in your grow rooms. More on this below. One has to be cautious about the use of UV light. It will cause sunburn and eye damage with exposure so handle this resource with care. After RO & UV treatment, input water should be an empty balloon ready for the addition of your perfect nutrient salt recipe. There are a wide range of low-cost UV lighting solution suppliers from which to choose and they are easy to find.

Dehumidification & Recovery (DEHU)

Early root follicles: Reaching for first nutrients

The number one way to conserve water in an accelerated growth aeroponic grow room is to recapture the humidity that is transpired into the air as the plants grow. While DEHU water is effectively distilled water (or clear of particulates), it can be full of healthy little bacteria or pathogens than may be transported through air or residing in the equipment filters. Clearing these with UV light normally makes this water directly reusable in your fertigation systems. Not all dehumidifiers are perfect. Some metals used in their construction can leach into the recovered water, so this is worth a deeper look as you create your complete water system. Air treatment suppliers are covered in Part 1 of this series.

Used Fertigation Water, or “Flush”

At the start of the flower cycle, take your clean water (the empty balloon) and add your perfect nutrient salt flower recipe and deliver it to your plants. Over the grow cycle from flower to harvest, your plants will use portions of your nutrients and your balloon contents will drift from your target recipe you’re your desired cycle, clear or flush your reservoirs and reset your recipe by refilling your balloon to your exact targets. The exiting nutrient-rich “flush” water can also be recycled into your source water feed since the salts and metals present can be cleared from the mixture through the same RO process that your source water goes through. The end result is perfectly good recycled water savings.

Oxygen Reduction Potential (ORP)

Healthy roots reach for water: Early veg when plants get rolling

ORP is a measurement of an oxidizing agent. Oxidizing solutions are a common and inexpensive method of disinfecting water before and during use in hydroponic systems. Oxidizers can be used to monitor and deal with the “cleanliness” of a nutrient water solution while it is in use. Several oxidizing agents exist with the most common being: hydrogen peroxide, chlorine, ozone and chlorine dioxide. The characteristics of each of these agents and how they interact with the organic matter in solutions is different. The ideal concentrations to use in each situation to kill or control pathogens is unique and one of the topics covered by our “Letters from the AEssenseGrows plant science team” on our website. That deep dive is the subject of another paper.

When you take all of these subjects together and they are done right, you should be able to recycle 95% of your source water with a professional water treatment & recycling system.

Here, I would like highlight the ultimate water hero: Ashley Hubbard, director of cultivation at RAIR Cannabis. For a quick tour of her water treatment and recovery room, see here. No one that I know manages water better than RAIR Cannabis and Ashley leads the team there.

To download the complete guide and get to the beef quickly, please request the complete white paper Top Quality Cultivation Facilities here.

Stay tuned for Part 3 coming next week where we’ll discuss The Right Build Out.

December 17, 2018

Seven Steps To Avoid the Green Rush Blues: Investigate Water Supplies Before Planting Cannabis

By Amy M. Steinfeld

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A clean, reliable water supply lies at the heart of every successful cannabis farm. It’s no surprise that the stakes for finding land with ideal growing conditions, including adequate water, are high. But new buyers (and lessees) caught up in the green rush often gloss over water rights or are unaware of California’s byzantine rules governing the irrigation of cannabis.

Water rights are complex. Water regulations applicable to cannabis cultivation are even more complex. And our new climate reality convolutes things further. Longer droughts, more volatile weather, political uncertainties, increased groundwater regulation and water quality concerns are exacerbating tensions over local and statewide water supplies. In many areas of California, landowners can no longer rely on local water districts to meet their needs.

A robust investigation of the property must consider water supplies. Because a property’s water supply is dependent on water rights, local ordinances, state regulations, politics and hydrology, it’s important to consult a water lawyer (and in some instances a hydrologist) before closing. A bit of foresight can prevent a grower from being left high and dry.

The following checklist provides a roadmap to conduct water rights’ due diligence. While many of these details are California-specific, this type of due diligence applies throughout the West.

Step 1: Identify Available Water Supplies and Consider Potential Limitations On Irrigation, Including Potential Future Changes

Conduct a site visit to identify existing water infrastructure, natural water features and existing or potential water service options. Next, determine if the property is served by a public water supplier. If that’s the case, the California State Water Resources Control Board (“State Water Board”) does not require any specific documentation to irrigate cannabis, but the water supply must be disclosed in the CalCannabis license application.

Groundwater is generally the best supply for cannabis, but the era of unregulated groundwater pumping is over. Many groundwater basins in California are now governed by the Sustainable Groundwater Management Act (“SGMA”), which requires water agencies to halt overdraft and restore balanced levels of groundwater pumping from certain basins. As a result, SGMA may result in future pumping cutbacks or pumping assessments. It’s imperative to identify the local groundwater basin via the Department of Water Resources’ Bulletin 118, and determine whether the groundwater basin is adjudicated or governed by a groundwater sustainability agency. Growers should also test the local water supply’s pH and salt levels because cannabis plants are finicky and water treatment can be cost prohibitive. If a new well is needed, growers should consult with their local county before drilling a new well. In some areas, moratoriums and restrictions on drilling new wells are on the rise.

As a rule of thumb, cannabis cultivators should avoid using surface water to irrigate cannabis. Surface diversions are subject to the California Department of Fish and Wildlife’s permitting authority. And under the interim State Water Board Cannabis Policy, commercial cannabis cultivators cannot divert anysurface water during the dry season (April 1 through Oct. 31), even if they have a riparian right that can be used to irrigate other crops. During the dry season, cultivators may only irrigate using water that has been stored off-stream. And even during the wet season, cannabis cultivators must comply with instream flow requirements and check in with the state daily to ensure adequate water supplies are available. Cannabis cultivators are also required to install measuring devices and track surface water diversions daily. And buyer beware, a groundwater well that extracts water from a subterranean stream may be considered a surface-water diversion. So be especially cautious if the well is located close to a creek or river.Develop a water use plan to optimize water efficiency

Step 2: Identify Water Supplies Used On the Property, Including the Basis of Right, and Quantify Historical Use

Review information on historic and existing water use. This may include past water bills and assessments. If there is a well on the property, the seller or lessor may have metering data, electrical records and crop data that can establish historic groundwater use. Cultivators must submit a well log to CalCannabis as part of the cannabis cultivation application. If surface water is available, the purchaser should review the State Water Board eWRIMs database for water rights permits, licenses, stock pond registrations and certificates, decisions and orders. The purchaser should also identify surface water diversion structures and review annual filings to determine compliance with all terms and conditions of the water right. Lastly, the purchaser should request all documents and contracts pertaining to water rights.

Realistically estimate water demand for irrigation and other on-site purposes.Step 3: Confirm Ownership of Right and Assess Any Limitations On Water Right

Determine whether the right has been abandoned, lost to prescription or forfeited. Evaluate the seniority of the water right, availability of the right, adequacy of place of use, purpose of use (must include irrigation), season of use, and quantity of any permitted or licensed post-1914 right. Determine whether historical diversions pursuant to an appropriative right support the full amount of the claimed right, and whether any changes to the water right are needed to support the proposed new use. Cultivators in California who plan to utilize surface water also need to file for a “Cannabis Small Irrigation Use Registration” to store water during the wet season for use during the dry season.

Step 4: Reconcile Water Demand With Available Supply

Realistically estimate water demand for irrigation and other on-site purposes. Develop a water use plan to optimize water efficiency (drip irrigation, rainwater harvesting, water monitoring, hoop structures) regardless of supply sufficiency. Many counties, such as Santa Barbara County, require that cannabis growers meet certain irrigation efficiency standards. Determine whether available supplies can meet all proposed demands, including plans for full buildout. If not, consider whether additional supplies are available for use on the property.

Step 5: Determine Water Supply Compliance Obligations

The rights associated with water supplies are defined by their source, the time frame during which supplies can be taken, the quantity of water to which the right attaches, and any limitations on the purpose of use of the water supply. There may also be reporting requirements associated with taking and using the supply—these can include requirements to report the quantity of water used as well as information regarding the end use of the water. Failure to timely report can have serious consequences. Cannabis cultivators are also subject to additional water quality regulations and restrictions, including waste discharge requirements pursuant to the State Water Board’s Cannabis General Order.

Step 6: Negotiate Deal and Draft Conveyance Documents

After obtaining an understanding of the water supply associated with the property, the property conveyance documents may be drafted to incorporate the transfer of rights associated with the property’s water supplies. These may include the assignment of contracts pursuant to which water supplies are obtained, the transfer of permits or licenses as to the water supplies, or the transfer of water rights arising out of a judgment or decree.

Step 7: Consider Unused Water Supply Assets That Could Be Monetized

To the extent the water supply rights associated with the property exceed the cannabis plants’ water demand, it may be possible to monetize unused or excess water supply assets through transfer of the rights to a third party.

If you have any questions about water rights related to cannabis cultivation it’s always in your best interest to contact an experienced water attorney early on in the process.

July 17, 2018

Food Safety: Do You Know What Is In Your Water?

By Radojka Barycki

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Water is essential for life and it is an important part of agriculture and food manufacturing. Water has many uses in the cannabis industry. Among the most common uses are irrigation, ingredient/product processing and cleaning processes.

Water can be the carrier of pathogenic microorganisms and chemicals that can be transferred to food through agriculture and manufacturing practices. Poor quality water may have a negative impact in food processing and potentially on public health. Therefore, development and implementation of risk management plans that ensure the safety of water through the controls of hazardous constituents is essential to maintain the safety of agricultural and manufactured food or cannabis products.

Chemicals can enter the water stream through several sources such as storm water, direct discharge into fields and city water treatment plans.Although there no current regulations regarding the water used in cannabis cultivation and processing, it is highly recommended that the industry uses potable water as standard practice. Potable water is water that is safe for drinking and therefore for use in agriculture and food manufacturing. In the United States, the Environmental Protection Agency (EPA) sets the standards for water systems under the Safe Drinking Water Act (SDWA.)The regulations include the mandatory levels defined as Maximum Contaminant Levels (MCLs) for each contaminant that can be found in water. Federal Drinking Water Standards are organized into six groups: Microorganisms, Disinfectants, Disinfection Byproducts, Inorganic Chemicals, Organic Chemicals and Radionuclides. The agriculture and food manufacturing industry use the SDWA as a standard to determine water potability. Therefore, water testing forms part of their routine programs. Sampling points for water sources are identified, and samples are taken and sent to a reputable laboratory to determine its quality and safety.

Microbiological Testing

Petri dish containing the fungus Aspergillus flavus.
Photo courtesy of USDA ARS & Peggy Greb.

Determining the safety of the water through microbiological testing is very important. Pathogens of concern such as E. coli, Salmonella, Cryptosporidium parvum and Cyclospora sp. can be transmitted to food through water. These pathogens have been known to be lethal to humans, especially when a consumer’s immune system is compromised (e.g. cancer patients, elderly, etc.) If your water source is well, the local state agency may come to your facility and test the water regularly for indicator organisms such as coliforms. If the levels are outside the limit, a warning will be given to your company. If your water source is the city, regular testing at the facility for indicator microorganisms is recommended. In each case, an action plan must be in place if results are unfavorable to ensure that only potable water is used in the operations.

Chemical Testing (Disinfectants, Disinfection Byproducts, Inorganic Chemicals, Organic Chemicals and Radionuclides)

Chemicals can enter the water stream through several sources such as storm water, direct discharge into fields and city water treatment plans. Although, there are several regulations governing the discharge of chemicals into storm water, fields and even into city water treatment plants, it is important that you test your incoming water for these chemicals on a regular basis. In addition, it is important that a risk assessment of your water source is conducted since you may be at a higher risk for certain components that require testing. For example, if your manufacturing facility is near an agricultural area, pesticides may enter the surface water (lakes, streams, and rivers) or the aquifer (ground water) through absorption into the ground or pollution. In this case, you may be at higher risk for Tetrahalomethanes (THMs), which are a byproduct of pesticides. Therefore, you should increase the testing for these components in comparison to other less likely to occur chemicals in this situation. Also, if your agriculture operation is near a nuclear plant, then radionuclides may become a higher risk than any of the other components.

Finally, in addition to the implementation of risk management plans to ensure the safety of water, it is highly recommended that companies working in food manufacturing facilities become familiar with their water source to ensure adequate supply to carry on their operations, which is one of the requirements under the 21 CFR 117. Subpart B – Current Good Manufacturing Practices (cGMPs) for food manufacturers under the Preventive Controls for Human Foods Rule that was enacted under the Food Safety Modernization Act in 2015. Also, adequate supply is part of the Good Agricultural Practices (GAP) The EPA has created a program that allows you to conduct a risk assessment on your water source. This program is called Source Water Protection. It has six steps that are followed to develop a plan that not only protect sourcing but also ensures safety by identifying threats for the water supply. These six steps are:

Delineate the Source Water Protection Area (SWPA): In this step a map of the land area that could contribute pollutants to the water is created. States are required to create these maps, so you should check with local and/or state offices for these.
Inventory known and potential sources of contamination: Operations within the area may contribute contaminants into the water source. States usually delineates these operations in their maps as part of their efforts to ensure public safety. Some examples of operations that may contribute to contaminants into the water are: landfill, mining operations, nuclear plants, residential septic systems, golf courses, etc. When looking at these maps, be sure that you verify the identified sources by conducting your own survey. Some agencies may not have the resources to update the maps on a regular basis.
Determine the susceptibility of the Public Water Source (PWS) to contaminate sources or activities within the SWPA: This is basically a risk assessment. In here you will characterize the risk based on the severity of the threat and the likelihood of the source water contamination. There are risk matrices that are used as tools for this purpose.
Notify the public about threats identified in the contaminant source inventory and what they mean to the PWS: Create a communication plan to make the State and local agencies aware of any findings or accidents in your operation that may lead to contamination of the PWS.
Implement management measures to prevent, reduce or eliminate risks to your water supply: Once risks are characterized, a plan must be developed and implemented to keep risks under control and ensure the safety of your water.
Develop contingency planning strategies that address water supply contamination or service interruption emergencies: OSHA requires you to have an Emergency Preparedness Plan (EPP). This plans outlines what to do in case of an emergency to ensure the safety of the people working in the operation and the continuity of the business. This same approach should be taken when it comes to water supply. The main questions to ask are: a) What would we do if we find out the water has been contaminated? b) What plan is in place to keep the business running while ensure the safety of the products? c) How can we get the operation back up and running on site once the water source is re-stablished?

The main goal of all these programs is having safe water for the operations while keeping continuity of the business in case of water contamination.