What does deep snowpack mean for the Carson River? Flood damage, longer recreation season

With this year boasting the most snow water equivalent in decades, it lends to the question, how will this affect the Carson River?

The Carson River is fed through the snowpack each year, with its flows directly tied to the water — or lack thereof — that trickles down the mountain as the pack melts throughout the spring and summer.

However, in addition to the snowpack, this year the Carson River has already received a large amount of precipitation, which led to numerous flooding incidents along the river corridor, especially in the areas of Morgan Mill, Riverview Park and Empire Ranch.

However, flooding of this level isn’t unprecedented according to Open Space Manager Lyndsey Boyer. Large flooding events seem to occur around once every 10 years; however, with the last flooding incident occurring in 2017, those intervals could be changing.

“This has definitely been a huge water year,” Boyer said. “We’re inches away from being the highest snowpack year on record.”

So far though the damage to trail areas has been consistent with what Open Space saw in 2017, Boyer said. What isn’t known, however, is how the increased snowpack may play out over the coming months.

“We don’t know exactly what the flows are going to be because it will depends on temperatures and weather,” Boyer said. “If we get big rain-on-snow events, we could see dramatic immediate flooding, but if there is a gradual warming, the increase will be slower. Only time will tell how high and how long it will be high.”

Even if storm intervals shift from every 10 years to every five years, Boyer said, it’s worth it for the department to repair the trails and put them back in their pre-flood condition.

“People love recreating by the river; it’s a great resource,” Boyer said. “If weather patterns significantly change, that would influence where we’re deciding to put trails. We’re always thinking about trails-resilient infrastructure;
we don’t want to put trials in areas they’re not going to be sustainable.”

In a worst case scenario, where there is a significant amount of erosion in one area, however, localized mitigation efforts can be used, such as planting willows to stabilize river banks and decrease bank scouring, or using rocks to shore up the banks in some locations.

While a higher river means the potential for more flood damage, it also means the potential for a longer recreating season for river aficionados.

“With high flow years, it allows people to run the river into August,” Boyer said. “A lot of people who are really hardcore rafters or kayaking enthusiasts love the high flow years because they can run the river for much longer than in typical years.”

In a typical, low-flow year, by midsummer areas in the river can become ankle deep, but in a high flow year, rafters and boaters could see a continuous experience even into August.

“If you’re more of a novice, or just looking to get out with kiddos or hang along the river, the flows through the early part of the season through May and even into June can lend to more dangerous conditions,” Boyer said. “People need to be aware of that.”

Carson City Parks, Recreation and Open Space provide a free aquatic trail map both online and in their office which is a great resource for learning how to recreate safely on the river, including where put in and take out locations are, as well as important safety information.

They also provide kayak rentals along with necessary equipment such as oars and life vests. First time or novice kayakers are encouraged to test out the river toward the middle to end of the summer season this year.

As far as the trails along the river corridor go, things are more tricky. Because of the recent flooding, some trails, such as Morgan Mill, are still closed, while others have become damaged due to the flowing flood waters.

With more storms incoming, it’s not known when those trails will be reopened or rehabbed.

“We already know there’s going to be some damage; during any high water year, the most impacted areas are along the river,” Boyer said. “When things have receded and the highest flows have gone down, staff already has plans to go into locations where flooding has occurred to mitigate the damage.”

Depending on the size of trails and the scope of the damage, Open Space may need to seek grant opportunities for any large-scale fixes that need to occur and, if heavy storm winters continue, they may even need to reroute trail systems altogether.

“If there are trails that are continually being washed out, we may look at moving it a little higher,” Boyer said. “But if it’s a relatively easy fix, we can go in with equipment and staff we have in house. It depends on the location and trail type, as well as the damage that was sustained to determine how we address those issues, but we know that (damage) is going to be rampant throughout the trails in the river corridor.”

To help mitigate the damage, the public is asked to follow some “trail etiquette” to help protect both the trail systems and the surrounding natural spaces.

For example, the Morgan Mill trail system remains closed, not only for safety issues due to the flood but to keep the public from unintentionally causing more damage.

In other areas where water is receding, trail users are asked to be thoughtful as it relates to recreation.

“We’re asking that, if a trail is super muddy and there are lots of water and puddles on the trail — if the conditions don’t look ideal, please seek other opportunities,” Boyer said. “If it’s decent, we’re asking people to be thoughtful as they’re recreating. If you’re on a bike coming up to a puddle, we don’t want people to go off the trail to avoid the puddle, as it causes resource damage and widens the trail.”

Boyer also warns that users should be cautious, as there is going to be some damage in locations even on the trails that are open.

While most of the trail rehabilitation must be done by machines and skilled laborers, for those who want to help in a hands-on way, there will potentially be volunteer opportunities along river banks to help mitigate erosion once the flows recede and the department can assess the damage.

What is most important right now, Boyer said, is having patience.

“We’re all stir crazy after being cooped up all winter, and people are eager to get out, but we’re asking for patience,” Boyer said. “Some areas may need to remain closed or may be damaged, and it will take us time to put everything back in order.”

To learn more about the Carson River, you can visit Carson City Parks, Recreation and Open Space for more information.