Big Dry Creek at South Suburban Golf Course

Stream

Project Overview

Big Dry Creek at the South Suburban Golf Course is a perennial stream system with a 12 square mile highly urbanized watershed. Over several years, the altered hydrology and sediment supply within Big Dry Creek contributed to a highly degradational system. Channel incision and widening, disconnected floodplains, damaged golf course infrastructure and created safety hazards.

Working for the Mile High Flood District (MHFD), Southeast Metro Stormwater Authority (SEMSWA) and the South Suburban Parks and Recreation District (SSPRD), ICON engaged a multi-disciplinary team of engineers, landscape architects and ecologists to assess the stream, develop alternatives and ultimately design and implement improvements. The Stream Restoration improvements utilized a variety of high-tech and low-tech process-based approaches.

Ungrouted boulder step-pool drop structures and riffle structures were strategically implemented to elevate the channel and establish connections with the floodplain. These structures also offered grade control and energy dissipation to manage the altered flow regime. Mechanical grading was employed to soften streambanks and create wetland bench habitat. On-site sourced rootwads were strategically placed in the stream’s outer bend to protect wetland benches from erosion and create diverse habitat conditions. Additionally, channel-spanning logs were introduced to provide intermediate grade control and foster bedform heterogeneity.

Riparian vegetation restoration and biostabilization were also a vital part of the overall restoration plan. Mature cottonwood trees were strategically protected to ensure the existence of a canopy layer. Wetland habitat was expanded along the stream through the creation of low benches. Species richness will enhance the removal of monoculture zones and the reintroduction of complex native planting palettes.

The resulting design, constructed in the Winter of 2023-2024, not only increased the stream and riparian corridor’s functionality but also prioritized human safety and protected infrastructure.