Slow-Go: East Fork Dredging Still at Mouth of Luce Bayou

In July, the City announced it was wrapping up West Fork dredging and starting on East Fork dredging. It took three months for the dredgers to dredge their way through the Royal Shores channel before they could even start on the East Fork. Since then, it’s been a slow-go as round trip travel times to the placement area get longer.

*Dredging Location as of 10/12/2021*. *East Fork at Mouth of Luce Bayou on right.* *From here, pontoons ferry the spoils back to the West Fork opposite Kingwood’s River Grove Park.*

*East Fork Dredging as of 12/3/2021. Photo taken from Huffman side of river looking SW toward Royal Shores and the FM 1960 Bridge in the distance.*

Since then, the dredgers have managed to remove about 300 feet of the tip of one sandbar blocking the mouth of Luce Bayou and Red Gully (on the left in the shot above).

*Looking upstream. Lots of dredging left to do. Between Harvey and Imelda, the sandbars in this area grew approximately 4000 feet.*

Note the sediment plume in the middle of the boat’s wake above. That indicates the shallowness of the river.

According to boater Josh Alberson, the depth through this reach of the river was reduced from 17 feet to about three feet between Harvey and Imelda.

Dredging: A Conveyance Issue

The dredging is far more than a recreational issue. The decreased conveyance of the river creates a sediment dam than backs water up and contributes to the flooding of homes. In fact, I passed by dozens of flooded and abandoned homes while looking for a place to launch my drone.

Mechanical Vs. Hydraulic Dredging

One can only wonder whether the City of Houston is using the right tools for the job. Even Stephen Costello, Houston’s Chief Recovery Officer, called mechanical dredging “unsustainable in the long run” when he addressed a crowd at the Kingwood Community Center on July 9.

But it may come down to a case of slow-go or no-go.

I asked a friend in the dredging business to estimate the costs of mechanical vs. hydraulic dredging. He qualified the discussion by saying that:

To even consider hydraulic dredging you need a pit to pump the material into.
He also suggested that to reduce long-term overhead costs, you want to be able to use the equipment year round and create a perpetual dredging program.

He said the ideal would be to go once around the lake and arrive back at the beginning when it was time to start all over again.

That said, he estimated that hydraulic dredging was 10X faster and one third to one fourth the cost of mechanical dredging.

With hydraulic dredging, the upfront equipment and setup costs are far higher. Mechanical dredging is far slower and more expensive.

This website has an excellent discussion about seven factors that drive dredging costs.

Engineering and permitting costs
Mobilization costs
Depth and type of sediment
Allowable run times
Transport distance
Disposal
Water management

I won’t pretend that I have the answer to the question of which is better in this case: mechanical or hydraulic.

Vendor for Long-Range Dredging Plan Due to Be Selected This Month

The submission deadline for vendors bidding on a long range dredging plan for Lake Houston was 9/23. The Request for Qualifications stated that the City hoped to put contract approval on the City Council Agenda for December and start the contract in January. The selected vendor will have two years to complete the dredging plan.

It could easily take that long to finish the East Fork Mouth Bar at the current rate.

Posted by Bob Rehak on 12/3/2021

1557 Days since Hurricane Harvey and 775 since Imelda