Description and History:
Flooding is a significant and potentially catastrophic hazard throughout Larimer County. Flood hazards include riverine flooding, flash flooding, stormwater and urban flooding, rapid snowmelt, ice jams, and dam-related inundation. Flash floods are particularly dangerous because they can develop with little warning and produce fast-moving water capable of sweeping away people, vehicles, and structures. Fort Collins and unincorporated Larimer County have significant to high flood risk, while Estes Park, Loveland, and Wellington are considered to have moderate risk.
Larimer County has a long history of destructive and deadly floods. Major events include the 1976 Big Thompson Flood, which claimed 144 lives and caused approximately $35 million in damage; the 1997 Spring Creek Flood, which caused five deaths, 62 injuries, and more than $250 million in property damage; and the widespread 2013 Colorado floods, which caused significant infrastructure damage and fatalities. More recently, post-wildfire flash flooding and debris flows have caused fatalities in the Poudre and Buckhorn Canyon areas.
Flooding can threaten people, homes, businesses, transportation systems, utilities, agriculture, and critical facilities. An estimated 2,831 residents live within the 1% annual-chance floodplain, with thousands more living within other mapped flood hazard areas. Floodwater can also create serious health hazards through sewage, chemicals, contaminated drinking water, mold, debris, and damaged electrical systems. One of the greatest dangers is attempting to drive or walk through floodwater; even relatively shallow, fast-moving water can knock down a person or carry away a vehicle.
Flooding is considered highly likely to continue in Larimer County, and climate change, population growth, development, and wildfire burn scars may increase future risk. More intense precipitation, earlier snowmelt, and rain-on-snow events could increase runoff and flash flooding, while additional development creates impervious surfaces that increase stormwater runoff. Continued floodplain management, updated flood mapping, responsible development, flood insurance, emergency warnings, and public preparedness will be important for reducing future losses.
Personal Preparedness for Floods:
Residents of Larimer County can reduce their risk from flooding and flash floods by preparing before heavy rain or rapid snowmelt occurs. Because flash floods can develop quickly, receiving warnings and knowing where to go are especially important. Larimer County recommends registering for local emergency notifications and having an evacuation plan in place.
- Know your flood risk. Check whether your home, workplace, or frequently traveled routes are in or near a floodplain, creek, canyon, drainage area, or wildfire burn scar. Larimer County notes that properties outside mapped regulatory floodplains may still have flood risk.
- Sign up for emergency alerts and keep multiple ways to receive warnings, especially at night or when traveling.
- Know where to evacuate. Identify routes to higher ground and have alternate routes in case roads or bridges become flooded.
- Build an emergency kit with water, food, medications, flashlights, batteries, chargers, important documents, pet supplies, and other necessities.
- Protect your property. Keep gutters and drainage areas clear, move valuables and important documents above potential flood levels, and consider flood insurance if your property is at risk.
- Never enter floodwater. Do not walk, swim, or drive through flooded roads. Fast-moving water can sweep away people and vehicles.
- Plan for pets and livestock and determine how you would evacuate them before flooding begins.
- After a flood, use caution. Avoid downed power lines and contaminated water, return only when authorities say it is safe, and have private well water tested if flooding may have contaminated it.
Important Information Resources:
Larimer County also provides a dedicated Flood Ready Larimer County guide as part of its preparedness resources. The following are trusted resources Larimer County residents can use to stay informed before, during, and after floods.
