To flood or not to flood – that is the question!
I asked Jeff Lindner, meteorologist for HCFCD, about the Halloween storms (as seen below). I also asked his opinion about how much rain along Cypress Creek in a ~24 hour period will flood the creek. His response:
“The Halloween rainfall event came toward the end of several weeks of wet weather over the area that have maintained a wet to saturated ground state. The event on Halloween produced a basin average rainfall of 2-3 inches across the Cypress Creek watershed and 3-4 inches across the headwaters along the Waller/Harris County line. Additionally much of this rainfall fell in a fairly short period of time of 4-6 hours in the late afternoon and early evening hours of Halloween. The widespread coverage of rainfall on top of already soggy ground led to more run-off than usual for this particular event. One thing to keep in mind is that each rainfall event is different: ground state, rainfall patterns, amounts, ect. And each of these variables will produce differing rises on the watershed. One thing to remember is there is a lot of capacity in the upper part of the channel compared to the lower portion of the channel…so it takes much more rainfall to fill that upper portion capacity than the lower portion.
The 24-hr storm totals that I look for with a normal ground state would be 5-7 inches to get Cypress Creek to bankfull or slightly above across much of the basin (or at least above a certain location).”
There you have it – Cy Creek will probably go out of its banks with a 5-7″ rainfall. During Harvey we had 30+”, Tax Day flood about 10-12″.
The storms which moved through the area on Halloween dropped 2.52″ of rain at the flood gauge station at Cypress Creek and Stuebner-Airline Road over a ~24 hour period. During that time Cypress Creek rose 14′ (fourteen feet). To the west, at the 249 gauge, 2.8″ of rain fell and the creek rose 15′.
True, this left the creek 7′ below top of bank. But it was only 2.52″ of rain. Clearly the situation along Cypress Creek is still critical. We have this large rise in Cy Creek in this area because Cypress Creek is the longest stream in Harris County and gathers a lot of water in its watershed. The amount of runoff is increasing because of increased development in the watershed (more runoff, less soaking in) and because of the increase in frequency and intensity of rain here on the Gulf Coast. We have no significant detention areas on Cy Creek so the water is forced into the creek for drainage, filling the creek easily. The graph below tells the story:
Nowhere can there be a greater argument for the need for a ‘Third Reservoir’ than here on Cypress Creek. Yet that takes money, money only the State of Texas or federal government has. If you are voting on Tuesday and don’t vote for a candidate who has ‘flood control’ at the top of their ‘to do’ list, you are voting against yourself.
HCFCD is “desilting” and cleaning Cypress Creek. This digger had removed a mound of dead trees from the creek at the TC Jester bridge. Kevin Johnson reports he saw the crew remove two automobiles and a wrecked air boat. Lots of trash in there left by the flood last year.
So, what’s next?
Update – Nov. 15, 2018
At the HCFCD meeting in Cypress last night, Matt Zeve, Director of Operations for HCFCD, stated that the contract has been awarded and work begun on the update of the 2003 study of Cypress Creek and its tributaries. Matt has instructed the consultant, Michael Baker, Int’l, to have the work completed in six months.
No dirt will fly at that point. Instead he will call a public meeting to review the findings and prioritize HCFCD’s activities. While HCFCD can begin work immediately on property owned by Harris County, all other work must wait on environmental permits and ROWs (right-of-ways). Unfortunately it will not be easy. Some of the citizenry are not responsive to flood mitigation needs and are uncooperative, necessitating the use of eminent domain lawsuits to obtain property or easements. However, Matt has in hand sufficient funds to complete anticipated detention and channelization needs.
September 20, 2018 flood meeting – Cy Creek Christian Church
In a public meeting sponsored by the Chamber of Commerce to update the public on Cy Creek flood mitigation, the Army Corps of Engineers and Matt Zeve of HCFCD spoke. Results:
- the Corps is involved in several studies around the region to improve flood mitigation. None of these studies directly involve the Cypress Creek area. However, there is the possibility that the Corps study of Buffalo Bayou (read Addicks/Barker dams issue) will recommend some nature of third reservoir to mitigate the flood flow from Cy Creek which flows southward to Addicks. While this may have some impact on downstream Cy Creek the goal is protecting the Addicks/Barker area. In any event these are 3 year studies which just began.
- Matt Zeve, Director of Operations at HCFCD, stated that Commissioners Court has already approved $400 million in bond funds for immediate use. Little of that is coming to Cy Creek. Zeve did state that they have let a contract to update a 2003 study of Cy Creek and its tributaries. He has given the contractor 6 months to complete the work, then he plans to begin work on all 9 tributaries and the Creek. When I asked him where HCFCD will get the $300 million or so to do this work he replied: “We already have it”. Apparently the federal disaster bill recently passed reimbursed HCFCD for previous flood work and he will use that money to work on all 9 streams and the Creek. There are a variety of strategies which can be used to increase channel conveyance of all the streams.
- Zeve also stated that they have begun the process of acquiring flood plain along the Creek, $100 million has been budgeted for this project. While, as a strategy, there is skepticism that this alone will be effective, Zeve indicated that the acquiring of land was but the first step toward creating larger detention areas which can mitigate flooding in the future. Stay tuned on this one.
- Priorities of HCFCD in the funding of projects: 1. Right of way acquisition; 2. home buy outs; 3. projects which have already been designed; 4. projects which help the most people.
It was interesting to have this update. However, a mechanism must be put in place for regular reporting of progress and project initiation as we go forward in flood mitigation. How do we do this?
No more debate – the bond passed by an overwhelming 85%. Unfortunately only about 6% of Harris County bothered to vote. In the Cy Creek area the turnout was better, around 13% of voters made their voice heard.
Harris County Commissioners Court has proposed a $2.5 billion bond for flood mitigation across the 22 watersheds in Harris County. The election, which will affect all Harris County citizens who own property because it is based on property tax, will be held August 25th, the anniversary of the landfall of Hurricane Harvey.
The Cypress Creek area suffered $135,000,000 in direct economic losses due to flooding, according to the Greater Houston Flood Mitigation Consortium’s report. Over 10,000 homes and/or businesses were flooded. Untold economic loss was incurred by business interests from lost sales, spoiled goods, etc. A year later hundreds of homes are still not repaired or habitable. Some businesses, such as HP, left the county due to repeated flooding, taking 3,000 jobs with them. Many home owners have abandoned their homes due to repeated flooding.
The proposed mitigation efforts by Harris County Flood Control, which will be paid for either by the bond funds or federal dollars which must be matched by local funds, are available for inspection at: https://www.hcfcd.org/media/2883/ddd-2018bondproject-tables-and-maps-2018-08-01-1430.pdf
The annual Harris County Flood Control budget is grossly insufficient to begin the necessary mitigation. The State of Texas has over $12 billion in a ‘rainy day fund’ but the governor has no intent, for unstated reasons, to send any to Harris County. Federal funds may be available at a later date but could be years appearing.
Where does that leave us? Patently, based upon repeated flooding over the last 5 years, Cypress Creek cannot handle the water which is coming to it. We need to modify the creek to handle the water or continue to routinely flood. Regardless of whether the County’s proposal is complete or correct, it is a means to begin a local effort to prevent further flooding. It is our view that we would be better off with the flood bond money than without it. The County states the bond will be sold incrementally over several years. The average tax increase will be around $5 the first year, increasing to around $5/month after several years.
It is up to the voters to decide: a small tax hike or repeated flooding of homes and businesses. Both the State of Texas climatologist and the Harris County meteorologist believe more frequent and intense rainfall events are in our future. We can either send the water downstream or send it to our homes. It is up to the voters.