By the 1980s, inadequate maintenance and uncoordinated development led Forest Park’s grounds into disrepair. In 1993, St. Louis voters passed a half-cent sales tax to benefit city parks. Half the funds went toward Forest Park’s restoration. Two years later, after extended consultation with community groups, park users and technical experts, the 67-member committee submitted a master plan. The City Council approved it and construction began. During the master plan and schematic design phase, the project team recognized that the now underground River des Peres historically defined the park’s spatial character of bottomlands, bluffs, and upland areas. However, reclaiming the river wasn’t a viable option because it now flowed through sewer pipes running along the northern and eastern park boundaries. CH2M HILL engineers worked with park architect John Hoal of H3 Studio exploring a way to connect the park’s many lakes and lagoons into one continuous waterway. The design team evaluated how the waterway would look and function during ordinary, drought and flood conditions. One of the challenges to the waterway was the park’s limited slope. While the upstream waterway drops 10 feet, the downstream portion only drops four feet. Despite the small slopes, the design team created rippling streams and waterfall features by using recirculation systems to increase the flow and velocity. The design also reduces dependency on city water. Prior to the renovation, park maintenance fed almost 3 million gallons per day of city water into the many separate water bodies. The design process has decreased city water usage to 1.5 mgd.

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Also, the design integrates engineering technology into park aesthetics. Pump facilities blend with the landscape, yet are accessible for maintenance. Extra structural reinforcement enables the natural looking ripples in the streams to withstand heavy flooding. Control structures such as weirs produce picturesque stream ripples and waterfalls. Before renovation a large concrete spillway connected Post-Dispatch Lake to a lagoon. To improve the appearance, the architects split the spillway into two levels of handicapped-accessible footbridges. Long flat rocks serve as weir structures beneath the bridges. CH2M HILL’s work continues although the construction is completed. A team including Cathy Barnett, Mary Lew, Walt Ogburn, and Elise Ibendahl assisted park staff in monitoring the waterway during the 2004 growing season. By the end of the year the team will complete a "Water System Operations Manual" for the City of St. Louis. On the 100th Anniversary of the World’s Fair, St. Louis dedicated the new river and restored park grounds.