Idaho Legislature Makes Changes Regarding The Domestic Use Exemption and Irrigating From a Well: Senate Bill 1222

On February 18th, 2026, Governor Little signed into law Senate bill 1222 which updates Idaho code regarding the domestic use exemption for wells and specifically focuses on the ability to irrigate a lawn or garden from a domestic well. These updates come in response to issues relating to the previous update to that section of Idaho code that took place during the 2025 legislative session. Last year I wrote an article detailing the 2025 changes and their implications, but for those that missed that article, here is a brief synopsis: On March 20, 2025 Governor Little signed into law Senate Bill 1083a that changed how the domestic use exemption for groundwater wells applies in Idaho subdivisions located in areas with groundwater development restrictions. Prior to that point, homeowners could drill a domestic well and use up to 13,000 gallons per day, including irrigating up to half an acre without obtaining a recorded water right. Under the Idaho Department of Water Resources’ June 25th Administrator’s Memorandum interpreting that new law, domestic wells used for the first time on or after July 1st 2025 in qualifying subdivisions would be limited to “in-home use” only (such as cooking, cleaning, and bathing), ultimately blocking irrigation for lawns, gardens, or landscaping without obtaining a formal groundwater right. This interpretation applied to all affected subdivisions regardless of when they were originally developed and to wells first used on or after July 1, 2025—even if the well was drilled earlier but not yet used. This legislative taking left many property owners unable to irrigate or have a lawn at all unless they were somehow able to secure increasingly scarce groundwater rights. Some stakeholders, including the Idaho Water Users Association, argued that the interpretation went beyond the bill’s original intent, which they say was meant to apply only to new developments.

Disclaimer: This article is meant to be purely informative in nature and should not be taken as legal advice or a legal interpretation IN ANY WAY. The views and opinions expressed here are those of the author and represent the author's personal understanding and opinions of the changes that have taken place.

How does Senate Bill 1222 change the the standards that were put in place last year?

The first and in my opinion most important piece of Senate bill 1222 is that it makes the restrictions on being able to irrigate a lawn from a well in our area apply ONLY TO NEW DEVELOPMENTS platted on or after July 1st, 2025. Lots in subdivisions platted PRIOR to July 1st 2025 are now able irrigate a lawn off of a private well even if that well was drilled after the July 1st deadline. In the wake of last year's legislation, many stakeholders argued that this was the intention of that original piece of legislation and that the Idaho Department of Water Resources interpretation released as an Administrator's Memorandum last June was an example executive branch overreach. I tend to be of this same opinion. What IDWR did last year amounted to a legislative taking and was a SERIOUS misstep that had immense negative impacts on private property rights. It greatly disrupted the vacant land market in our area making vacant land prices go up significantly for properties that had another means of irrigation and reducing the values of those properties whose only means of irrigation was a domestic well.

Secondly, Senate bill 1222 clarifies that a subdivision is classified as being a partitioning of land into 5 or more lots. If a new project or development is 4 or less lots, than the rest of the restrictions barring owners from being able to irrigate a lawn off of their private well does not apply and the owners of said lots would be permitted to irrigate up to a half acre under the domestic use exemption similar to how things were before the original changes happened in 2025. To simplify, divisions of 5 or more you cannot water off of a well in our area, 4 or less and you are good to go. Please note that these restrictions only apply if properties are within an area where ground water development is restricted (moratorium area, groundwater management area, critical groundwater area). As you will see on the map I have attached below though, essentially the entire upper snake river plain is within these restricted areas.

Map of moratorium areas, groundwater management area, and critical groundwater areas in southern Idaho

What does this mean moving forward?

1. Vacant land prices will continue to climb. I believe that most people are not going to want to buy a building lot unless they know that they can have water for irrigation to that building lot. Because of this, developers will be required to put in some sort of delivery system to provide irrigation water to the lots. In most cases, these will be pressurized irrigation systems which are quite costly to install. Additionally, the developer will almost have to acquire surface water rights when purchasing the land where previously the farmer or seller may have been able to retain those water rights. If sellers are parting with those water rights, they will certainly want to be paid a premium for them by the developer which will lead to higher acquisition costs that then gets passed onto the end consumer.

2. HOA's will become increasingly more common. Think about it, if there is a $100,000 pressurized water system put in place to service a subdivision, there has to be someone in place to manage that system including sending out assessments for repairs to the system as needed. In fact, Idaho code requires that if a system has been provided then the entity in charge of that system has to have been set up in such a way that sufficient capital will be provided to maintain that system. If a developer has not designed or set things up in such a way as to meet this requirement, then they are guilty of a misdemeanor subject to the provisions of Idaho Code section 50-1329. Even from a practicality standpoint alone though, seeking to get 20 landowners to all agree and pay their fair share when repairs are needed is an exercise in futility. Additionally, it has been my experience when talking with watermasters and canal company presidents that their preference is for the HOA to own the canal shares/water rights as then the canal company only has 1 person to deal with rather than numerous property owners occupying a development. Due to these practicalities, I believe that HOA's will be formed for virtually every new development in our area.

3. Owners of lots in subdivisions platted on or after July 1st, 2025 will still not be able to irrigate a lawn or garden off of their private well that they paid for if that well was drilled and first used after July 1st, 2025. Most divisions will have some sort of water system provided given these new restrictions but buyers should beware of buying a property in a division platted after this date if no other means of irrigation has been provided.

If you have questions regarding what this means for you and how it affects all things real estate in Southeast Idaho, then give me a call at (208) 281-7258. Or to receive future similar articles, text SUBSCRIBE to (208) 281 - 7258.

You can read the full text of the bill by clicking the link here: https://legislature.idaho.gov/wp-content/uploads/sessioninfo/2026/legislation/S1222.pdf