Future of River Grove Boat Launch Discussed at KSA Meeting
6/7/24 – Last night, the Kingwood Service Association (KSA) Parks Committee discussed the future of its River Grove boat launch. As reported previously on ReduceFlooding.com, the boat launch has become seriously blocked by sand and other sediment coming downriver during the May floods, primarily from the West Fork San Jacinto.
After floods in January, boaters complained of difficulty navigating through the sediment to the river. So KSA commissioned a sonar study. It showed that approximately 11,500 cubic yards of sediment needed to be dredged to open the channel. The cost approached $800,000…without any contingency funds built in.
KSA’s board authorized the Parks Committee to spend the money at its April Board Meeting. However, board members also requested the Parks Committee to explore ways to lower the cost first.
During that exploration, May floods deposited even more sand. To avoid surprise overages, a dredging subcommittee asked the low bidder to do another sonar survey. The new survey indicated that the amount of sand needing removal increased about 50 percent.
Budget-Busting Costs
The cost – without any contingency funds for overages – represents 49% of KSA’s current Capital Assets Reserve Fund balance. And that prompted many tough questions from the Parks Committee. Especially since boat dock usage represents only a small part of KSA’s responsibilities. And because a relatively small percentage of Kingwood residents use the boat docks.
Through June 5, KSA has issued 837 boat trailer stickers. Compare that to 23,842 regular vehicle stickers. Only 3.5% of the vehicles using Kingwood parks use the boat launch.
Meanwhile East End Park needs extensive trail restoration after the last storm. And KSA is about to renovate the entry at Kingwood Drive and US59.
Note, however, that the mouth of the Kingwood Diversion Ditch (at the boat docks) also plays a role in flooding. The ditch drains the western third of Kingwood. And when it became blocked during Harvey, hundreds of homes behind the blockage flooded.
Options KSA Considered
Here is a slight revision of the River Grove boat launch presentation that the KSA Parks Committee reviewed last night. The revisions reflect changes discussed in the meeting.
To make it easier to understand, I’ve also shown the individual pages below with some background information.
The title slide shows sediment buildup at the mouth of the Kingwood Diversion Ditch in River Grove. Not only does it affect boating, if sediment continues to build, it could eventually back water up into homes as it did during Harvey.
The next section of the presentation covered developments since the last Parks Committee meeting.
After the first sonar survey of the River Grove Boat Launch in February, the Dredging Subcommittee authorized a second survey to quantify the amount of additional sediment deposited by May storms and the cost impact…even as it looked for ways to reduce costs.
The amount of sediment requiring removal increased 50% during May. The low bidder proposed hydraulic as opposed to mechanical dredging which is much faster. And the sediment would go to a property owner on the south shore of the river, instead of being trucked away.
The slide below shows an estimate of the revised costs and the current balance in KSA’s capital assets reserve fund. The River Grove Boat Launch dredging would consume 49% of KSA’s fund balance. Even though more sand is being dredged, the ability to pump the sand across the river helped to keep direct dredging costs close to the first estimate.
What to Do? Options Considered
With all that as background, the next slides present additional dimensions of the problem. The photo below shows the confluence of Spring Creek (left) and the West Fork (right) at US59. Sediment is now coming downriver from the West Fork after flowing through a mile-long sand pit.
The photo above helps explain the sediment build up at the River Grove Boat Launch: 5+ feet in places at the mouth of the Diversion Ditch and an average of 1.5 feet across the entire dredging area.
The dredging-company representative said he’d never seen anything like it in that short of a period.
And a retired Army Corps representative who helped lead the Emergency West Fork Dredging Project after Harvey said, “After we completed our survey of the area, we predicted sedimentation will be a perpetual problem at this location.”
Hydrologists call the photo below a “difference map. The colors represent the difference between the first and second surveys. It shows the build up between mid-February and mid-May outside the River Grove Boat Launch. The red, orange and yellow areas show the greatest build up. Blue and green show the lesser areas.
Note the options listed on the left. They set up a discussion of the pros and cons for each alternative.
Pros and Cons of Options
For the sake of brevity, I’ll let you read the pros and cons from the visuals in the following slides. They are fairly self explanatory.
In the first option, KSA would seek help with dredging costs. This became a possibility when the Governor and President issued disaster declarations for this area last month. Suddenly, federal money became available for debris removal and flood mitigation. The sand deposits might qualify under either.
Council Members Fred Flickinger and Twila Carter have already reviewed the pre/post surveys and forwarded them to the City’s Chief Resilience Officer, Stephen Costello, for help with developing an application.
However, the outcome won’t be known for a while. So, if that option fails, KSA could make the decision to dredge one more time using its own money. But if a hurricane should come along and fill the sand back in, then KSA would wipe out its capital asset reserves fund. Hence the emphasis on “ONE” below.
Another option the Parks Committee agreed to explore was asking the City to dredge. The City is strapped for cash right now, but if the City could get funds from FEMA to cover the removal, it might be possible. That’s because the City already has a dredge in the river for a separate project between Kings Point and FM1960.
If FEMA covered the sand deposited after the first survey, perhaps a cost-sharing arrangement could be worked out with the City for the rest.
After all, the City owns the lake and the lake is developing a sediment problem. The City also has responsibility for maintaining the outfalls of the ditches around the lake.
While discussing ways to reduce dredging costs, KSA’s low bidder suggested long-term ways to make periodic dredging more affordable and sustainable.
This is not an immediate answer to the problem, but could be considered as a follow-on option if one of the others becomes possible.
Example: the dredging company suggested building a jetty to deflect floodwaters out into the river instead of letting them curl into the gap between the islands.
They also suggested building low underwater rock walls that could catch sand scooting along the riverbed. This could trap sediment behind the walls. And that could help minimize the area needing dredging in the future. Hopefully, that could also make dredging more affordable and sustainable in the future.
However, the permitting and construction costs for those measures would be in addition to any dredging done now.
Some people on the parks committee felt the jetty might work in small floods, but not in larger ones like we just had.
KSA also considered an option to just close the boat dock. However, after discussion, a compromise became clear: just limit its use.
This would let families with smaller watercraft, such as canoes, kayaks and paddle boards, continue to use the facilities if they could portage over the developing sand bar. Large boats would have to seek other places to launch.
Next Steps and Timetable for Decision
The Parks Committee agreed that the options needed to be shared with HOAs and residents. Hopefully, after debate, public comment, and more exploration of the options, consensus may develop around one of the options. The community can then make a decision in the fall when people return from summer vacations about both short- and long-range plans for the River Grove boat launch.
Make Your Feelings Known
If you live in Kingwood, please share this post with friends and neighbors. And make sure you register your opinion with your homeowner association officers.
Even though most residents don’t use the boat launch, many people might like to have the option. And that option could affect home values. For instance, imagine if a potential buyer for your home someday owned a boat.
Posted by Bob Rehak on 6/7/2024
2474 Days since Hurricane Harvey
The thoughts expressed in this post represent opinions on matters of public concern and safety. They are protected by the First Amendment of the US Constitution and the Anti-SLAPP Statute of the Great State of Texas.
