Growing or Processing Facility Wastewater FAQs

Is there a specific wastewater permit or authorization required for cannabis wastewater discharge?

No, there is not a specific wastewater permit or authorization required for cannabis at this time. However, see below for additional information on wastewater discharges to public utility sanitary systems and engineering plan review.

Is there anything special I need for my wastewater system to support a cannabis growing or processing facility?

There is nothing of specific concern about the growing or processing of cannabis for your wastewater system that is not already applicable for similar agricultural activities. Examples could include commercial greenhouses, farms, agricultural product processing facilities, etc.

If I want to begin growing or processing cannabis, what steps should I take regarding wastewater?

It is important to understand that wastewater generated in the production of cannabis, both commercially and privately, is considered non-domestic wastewater according to state regulations Alaska Administrative Code (AAC) 18 AAC 72, Wastewater Disposal:

• 18 AAC 72 (PDF)

On-site septic systems and public sanitary systems are designed to treat domestic wastewater, which is wastewater generally derived from toilets, sinks, showers and laundry use.

If your intended facility will be or is connected to a public sanitary sewer, and you intend to dispose of the non-domestic wastewater to that sewer, you should contact the owner and/or operator of the sewer. The owner and/or operator will likely ask you to explain how much wastewater you will be generating and the expected chemical characteristics of the wastewater such as fertilizers, pesticides, solid material, etc. The owner and/or operator of the system will inform you if your connection is acceptable or if additional treatment of your wastewater is required prior to disposing of it in the public sewer system. The owner and/or operator also may elect not to accept non-domestic wastewater since it could adversely impact their treatment works.

If your intended facility has an onsite septic system or other on-site wastewater system such as a holding tank that you propose to receive wastewater from your operations, you will need to have the system reviewed by a professional engineer licensed by the State of Alaska prior to disposing of the non-domestic wastewater into the existing system. The existing on-site system was likely not designed to accommodate a non-domestic wastewater. A licensed professional engineer can evaluate your existing system and determine if the system can accept a non-domestic wastewater and still function in a manner that protects public health and the environment. Your engineer would submit a plan to the Alaska Department of Environmental Conservation (Department) Wastewater Discharge Authorization Program, with an appropriate plan review fee, for approval to modify the use of the system, along with any necessary system modification needed to accommodate the new waste stream.

Note discharge of the wastewater directly to surface water (e.g., marine waters, lakes, ponds, rivers, streams, wetlands, etc.) is discouraged and may only be done after obtaining an Alaska Pollutant Discharge Elimination System (APDES) permit from the Department’s Wastewater Discharge Authorization Program. APDES permits can take several months to issue and contain routine monitoring and reporting requirements to be conducted and paid for by the permittee to verify the discharge is not adversely impacting surface water quality.

What are the fees for an on-site wastewater plan review?

The plan review fees are located in 18 AAC 72.955, Table C. The fees are determined by the design daily flow of the system under review.

Are there other options besides modifying the existing on-site system?

Yes. Your engineer could elect to completely segregate the non-domestic wastewater and treat or store it separately from the domestic wastewater. You can discuss these, and other options with your licensed professional engineer.

Can you recommend an engineer?

The Department does not provide a recommendation of engineers in the interest of being fair and impartial. Any professional engineer in civil or environmental engineering licensed by the State of Alaska may submit sealed wastewater plans to the Department for review. The internet, telephone book and talking with local contractors are all sources of information for locating licensed professional engineers.

How long will a plan review take?

Once the Department receives a complete plan submittal, we issue a response within 30 days.

What if I grow or process cannabis in my home or don’t do it commercially?

From a wastewater perspective, the location or commercial activity doesn’t change the fact that wastewater from that activity is non-domestic.

Is there a certain threshold where it’s just too small to worry about?

The Department has not established a certain size of agricultural activity below which there is no concern. If you have questions, you should consult with a licensed professional engineer to evaluate your operation and the specifics of your on-site wastewater system.

What if I simply do not generate any wastewater requiring disposal from my growing or processing operation (i.e., closed loop, recycled system; zero disposal)?

Approval of wastewater discharge or disposal is only required when the wastewater is intentionally released to lands or waters (surface water and groundwater) of the State. If disposal or discharge is not planned, then approval from the Department’s Wastewater Discharge Authorization Program is unnecessary.

What could happen if I don’t evaluate my on-site system and just put my non-domestic wastewater in it?

First, the system could cease to operate as it was designed to. You could overload the system with too much water and cause it to fail. Failed systems can “daylight”, which means the partially treated wastewater would be above ground and become a public health hazard. Additionally, any non-domestic wastes present in the wastewater (e.g., pesticides, fertilizers, etc.) would now be disposed of in the ground. These chemicals could enter the groundwater and potentially contaminate public or private drinking water systems threatening public health.