Missoula Water Rights
Water is Montana’s lifeblood, and as a result, we Montanans take it pretty seriously.
Snowy winters lead to great skiing, full reservoirs, and flowing streams. Rainy summers can mean (generally) fewer wildfires and clear skies. Cold water translates into happy trout (and happy outfitters). Full rivers mean great floating, great irrigation for ranchers, and serve as a draw for tourists.
People are drawn to water, and often want to live as close as they can to it. Whether your dream property is near a river or not, chances are you’ll still have to learn how different rules and regulations having to do with water might impact you.
So let’s navigate a few things …
Surface Water: Lakes, Rivers, Streams, and Creeks
The term “surface water” refers to any body of water above ground, including streams, rivers, lakes, wetlands, reservoirs, and creeks. There are several iconic lakes in western Montana (think Flathead Lake), and hundreds of rivers and creeks.
If your property is located near a river or creek, chances are your property boundary might be part of (or adjacent to) a floodplain. The actual expanse of a floodplain varies widely, but generally stretches from the outer edges of the bank to the edge of the river valley.
So what are some best practices to follow when living near surface water, especially rivers and creeks?
Check with your local county planning office for the rules and regulations. From the Missoula County website: “a Floodplain Permit Application must be submitted and approved by the Floodplain Administrator prior to all development activity to assure the County and the property owner that all applicable flood code standards have been met.”
Keep in mind that “development activity” can refer to much more than just a home -- it also refers to outbuildings, bridges, roads, etc. Make sure you (or your builder) have contacted the County and have the right information you need to get started.
Design your structures to be sited on stable soils away from streams. Avoid siting on steeper slopes, to prevent sediment runoff into the stream.
As you consider your landscaping, strive to maintain the floodplain in its natural state. The riverside vegetation provides valuable shade to keep the river temperatures optimal for trout, and the native trees and bushes that have existed along the rivers for decades provide habitat for birds, deer, and other mammals.
The Federal Emergency Management Agency (FEMA) has mapped nearly every inhabitable watershed in the West and sets rules and regulations to ensure that homes are built to standards that reduce (or eliminate entirely) their vulnerability in the event of a flood. And the truth is, in most cases nowadays in Montana, building homes right on the river just simply isn’t allowed anymore due to the potential of flooding.
Now, you might think, “OK, why can’t I build my home here? It’s over 100 yards from the river.” The answer is, sure, it’s 100 yards from the river right now, but that can change in a short period of time. Rivers in western Montana, like the Clark Fork and Bitterroot Rivers, start high in the mountains and gather multiple trickles and streams as they grow and gain force to form one large river. These rivers also flow through broad valleys, which allow the rivers to meander over wide expanses, carving new channels and taking once stable ground with them. So the short answer is -- just because you’re 100 yards from the visible river that you can see with your naked eye, the river is still moving and changing every moment.
Subsurface Groundwater: The Secret Life of Water
Just like it sounds, subsurface groundwater is water that is not visible to you or me, but sits below the surface. In the case of Missoula, we have a large, plentiful aquifer that sits below the valley floor, and this aquifer is the source of our drinking water.
The aquifer is continually recharged by rainfall and winter precipitation and sits just 10 to 100 feet below the surface across the valley floor. While this subsurface groundwater rarely impacts home building, it absolutely impacts your ability to site and place a septic system on your property.
If you’re looking to build a home outside of city limits, and that is not on city sewer, you will need to follow the regulations to site your septic system and well. Make sure to do your research on your property and what the regulations are to ensure you have enough room for a new septic AND a well (with enough distance between), a drainfield, and a replacement drainfield.
More info on septic systems and wells in Missoula County can be found at the Missoula County Health Department website.
Plus, check out this educational video from the Clark Fork Coalition about Missoula’s aquifer, called The Hidden Life of Water.
Montana is still a wild place, where nature is your neighbor. A big winter followed by a warm spring can send water out of the mountains in a hurry. If you’re fortunate to own property alongside a river or stream, do your homework and proactive planning before you build and place your home in a spot that’s safe and secure, as well as beautiful.
Here are a few more resources to help you navigate the rules and regulations that were put in place to keep you and your property safe:
Flood Maps from FEMA:
https://www.fema.gov/flood-maps
Missoula County Floodplain Maps: