The Harris County Flood Control District closed on the purchase of the Raveneaux Country Club Thursday, a key step toward converting the property into a giant stormwater detention basin.

The county paid $11.5 million, the current appraised value of the property, for the 27.6 acre site, said Matt Zeve, the Flood Control District's deputy executive director. The county would not immediately release its appraisal.

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The acreage includes the club house, driving range, swimming pool and tennis courts at 9415 Cypresswood Drive. The latest Harris County Appraisal District's value of the property is $2.5 million. The deal includes a leaseback, allowing the club to continue operating for up to one year.

The district also wants to buy the more than 200-acre Raveneaux golf course. Officials plan to combine the properties to create one of the county's largest detention basins aimed at flood mitigation in the Cypress Creek watershed. Hundreds of homes in this northwest Harris County area were inundated during Hurricane Harvey and other recent floods.

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Zeve has said the basin would likely hold water as well as provide recreational areas.

Residents of the Champion Forest neighborhood adjacent to the club have been critical of the county's plan. Some believe a flood mitigation project could be done in conjunction with maintaining Raveneaux. To that end, county officials recently met with a real estate broker and a golf course architect to discuss options.

The clubhouse property was owned by Dallas investor Michael Block through entities called Kera Development LP and Cypress/Raveneaux LLC. The golf course is owned by the Cypress Forest Public Utility District. The Flood Control District plans to meet with the Cypress Forest PUD next month to discuss acquiring the golf course land.

Community engagement meetings are being planned for late March. Zeve said details will be forthcoming on the county's web page dedicated to the Raveneaux project.