I just took a look at FEMA Flood Profiles for the area… 500yr BFE at Camp Mystic is approximately elevation 1,850’. Right at my “guesstimate” of the July 4 flood elevation.
FEMA’s 500yr Flood Elevation at the Hunt USGS Gage is 1,760’. The High Water Mark measured by USGS after July 4 is 1,760.3’ (37.5’ flood depth + 1,722.8’ elevation at bottom of gage).
That flood was right at the 500-yr elevation based on FEMA’s models. 500-yr storm is more accurately described as a 0.2% annual chance storm event. Low probability, but not zero.
Question everyone faces is, what is an acceptable risk? 1% annual chance? 0.2%? Do we design and build for even less frequent storms, like the 1000yr storm (0.1% annual chance)? The 100yr storm event is typically used as the design event in most places… is it enough?
Good stuff there, I appreciate the insight. I agree the failure was at the local (County) level for Camp Mystic. I hope they make meaningful changes to prevent this from happening again.
And I hope other communities across Texas and the US are looking at their own emergency action plans and notification systems. We’re seeing these catastrophic floods across the country at a pace I don’t recall hearing about in years past. I really do believe the warming climate contributes to the more intense rains and higher overall rainfall depths experienced across the country.
I lived pretty close to where the US record for 24-hour rainfall was set in 1979 (42 inches in Alvin), when Tropical Storm Claudette dumped on us in a way that seemed like it would never end.
Maybe the climate has changed since then, or maybe people have just continued to build in places that were avoided in the past - maybe some of both. I know a fair amount of the parts of Kingwood that flooded during Harvey were once considered swampland that nobody would ever live in. Whatever the case, we for sure have more coverage and video footage of weather events than we’ve ever had before.
Hurricane intensity is the one weather feature that seems to have objectively gotten more extreme, but we also have a greater capacity for more regular measurement and monitoring than we’ve ever had, so even that is kind of questionable.
As far as the Hill Country, this area has been in an historic drought for several years. You might say the area is overdue for flooding rains, which are part of the normal long-term weather cycle. I don’t think arguing over the causes of weather is particularly helpful. We just need people to acknowledge the very real dangers and take steps to protect against them. It seems like our nation (or at least our state) has regressed in that regard.
Good information and Mother nature is always right. If there is one lesson to learn here is that we can’t build in a flood prone area no matter how we want to. These families and their friends need our prayers and our support.
Update on camp Mystuc taking action. Earlier said it was 2:30 am before action was taken. but walked it back a bit.
The information provided by Carr provides one of the first windows into the late-night scramble that took place at the isolated camp, where 27 counselors and campers lost their lives in the flooding.
Carr previously told the Washington Post that the evacuations began at 2:30 a.m. but walked back the timeline when speaking to ABC News. He cautioned that the timeline determined by the family is preliminary and estimated the evacuations began closer to 2 a.m… He said the timeline was pieced together based on the accounts of family members who assisted in the evacuation and Camp Mystic’s night watchman.
Do they do cloud seeding in mainly rural areas? I know it’s a fact they do it and maybe the federal gov needs to ok where they are doing it bc in the end it hits the federal government’s pocket book.
You are correct, going off of HCFCD gages. For Harvey, gages across Cypress area were 1’-1.5’ above the 500yr, and then right at the 500yr across the Spring area.
These are based on the “latest” FEMA models… which date back to 2001 (after TS Allison). They were the state of the art at the time.
HCFCD has new floodplain models based on even newer technology that were completed several years ago and submitted to FEMA for approval. HCFCD has been trying to drag FEMA into the 21st century to get them released, but FEMA can’t figure out how best to represent these new maps. And then losing a lot of FEMA staff hasn’t helped.
The new floodplains also reflect more accurate rainfall statistics. New 100yr rainfall is 16"-18.5" in 24 hrs, where the previous maps assumed a 100yr storm was 12.5"-13.5" in 24 hours.
I’m curious how the new maps (MAAPnext) compare to the old. The data should be more accurate but also likely show some results that property owners won’t be happy with. The old “I’m not in a floodplain, I’ve lived here 30 years and never flooded” argument.
I agree to an extent, but it’s hard to make a “one size fits all” regulation.
For instance, we’ve got different terrains to consider. Flat coastal Houston vs. steep Hill Country. We can “terraform” our land here in Houston relatively easily, cutting and filling to create high ground for developments and creating mitigating storage for floodplain. You can’t do that in the Hill Country – building safely is based strictly on elevation. Don’t build below XXX-year floodplain. But, what’s the right elevation, which floodplain? Best I can tell, the Camp Mystic cabins that flooded were above the 100-yr floodplain elevation…but it was a 500-yr flood.
Same with Cypress Creek 500-yr flooding that Kyle described above. If we build to the 100-yr standard, there are still thousands of homes flooding in a 500-yr event.
Also consider that “the floodplain” isn’t a static condition, it’s subject to change as the terrain changes, as we get better models, as the rainfall statistics change over time (increasing rainfall intensities.) What we build today is intended to last for what, 50-100 years or more? The floodplain 50 years from now won’t look the same as it does today.
You can keep chasing your tail forever, and it comes down to a question of what is an acceptable risk? There’s not a simple answer.
I’m not sure it’s been proven to have caused any floods anywhere. They don’t seed storm clouds, and seeding doesn’t cause severe weather, from what I’ve read. Admittedly, I don’t spend my time reading conspiracy theories because they’re pretty much all the same.
The state regulates and approves whatever cloud seeding activities are going on, at least in Texas. Before the Guadalupe flood, the nearest cloud seeding activity was at least two days earlier in Karnes County, about 150 miles southeast of the areas where the big rain fell. These rains generally developed from the west and southwest, much like they’ve been doing for the last several days.
It’s going to be hard to know exactly what happened and when. From a liability standpoint, I cringed when I saw their initial timing estimates - they should have just said they’re still figuring that out. I can’t imagine the trauma of having to relive that experience over and over.
People are going to continue to build along rivers and coasts. I think that’s mostly manageable, but it clearly requires additional safeguards if those buildings are going to house guests, whether it’s a kids’ camp, hotel, RV park, or a vacation rental. Local governments need to do more to ensure that alerts get to the right people in time to take action, but owners who allow their guests to stay in harm’s way (and a 100 year flood zone definitely qualifies) have to be more proactive and alert.
With all of our technology, it doesn’t make sense for us (as a society) to struggle to get information distributed.
I guess you can address whatever you want. You’re not going to make flooding go away, because it’s always been here. This wasn’t the worst flood on record in Kerrville or several other places downstream, so maybe it’s more productive to focus on prevention and warnings, as these are things that can be controlled and quickly improved.
Today our Rotary guest speaker was a retired FEMA guy.
He told us that The US Geological Survey has an alert system all over our USA that can warn of danger.
He said that Kerrville has 5 such stations on The Guadalupe. Went on to say that you can sign up for their free service and then get text message alerts, such as for rising rivers.
Basically Camp Owners could have received text alerts when that River hit a certain level. As it rose toward flood stage.
He also agreed that a Siren system would be ideal and that a Tower costs $75,000.
Neither Kerr County nor The State of Texas had the $75,000.
