The Willow Waterhole Greenspace Conservancy was formally established in April 2001 as a non-profit organization of community partners, dedicated to the establishment of a major park in Southwest Houston. Its objective is to assist and nurture the partnership of the Harris County Flood Control District (HCFCD) and the City of Houston Parks and Recreation Department in the development of this park and others like it throughout the City of Houston. The Willow Waterhole will have a series of interconnected permanent lakes suitable for fishing and boating with a variety of recreational amenities and an emphasis on conservation of our natural resources.

In 1996 the idea of a storm-water detention pond adjoining the Willow Water Hold Bayou near Westbury High School was proposed to the Brays Bayou Association as a means of reducing flood risk in the Brays Watershed. With the prospect of a storm water detention site in this area, it was suggested to incorporate a park on the detention site. This idea was proposed to the Brays Bayou Association (BBA) and to the Westbury Area Improvement Corporation (WAIC). In late 1999, the BBA, whose mission was reducing flood risk in the Brays Watershed, decided to sponsor a new organization whose principal purpose was the establishment of a park on this site.

In early 2000, the Texas Parks and Wildlife Department initiated an Urban Parks Grant Program. The city of Houston Parks and Recreation Department prepared an application from the flood control work done by HCFCD as well as the concept drawings of the SWA Group for the BBA. The application was submitted at the end of March 2000 and in early April the City heard they would be awarded a $750,000 grant for the first phase (60 acres of a total of 250) of the project. In November of 2000 a formal launch of the Willow Waterhole Park Project was held on the future park site.

Also, in 2001, the Willow Waterhole Greenspace Conservancy received support from the National Parks Service and the acquisition of more land to increase the size of the park.