Synthesis of New Methods for Sustainable Roadside Landscapes

Several Texas Department of Transportation (TxDOT) districts have developed innovative landscape efforts specifically seeking to establish sustainable landscapes that require little if any supplemental water and utilize no chemical fertilizers. The concept behind this approach is that as land use intensifies, surface water runoff increases and the soil's ability to absorb runoff diminishes. TxDOT needs creative alternatives that can help soil retain moisture and recycle nutrients to reduce the energy expended in the maintenance of right-of-way landscape development. Techniques that utilize the environmental processes found in natural self-sustaining, and self-sufficient plant communities have been clearly demonstrated to minimize and restore development impacts on soil, reduce peak storm flows, and increase infiltration. These techniques include major soli modifications as part of large-scale highway plantings. This project identifies many of the common non-chemical soil amendments and additives that can be used to create an environment that simulates a naturally occurring sustainable system found in undisturbed landscapes. Alternative management practices used by the public and private sectors were investigated for possible application to urban roadside landscapes for TxDOT and included cost and benefit evaluations, and the analysis of traditional and more sustainable landscaping comparisons of maintenance, water use, erosion control, and pollutant runoff mitigation. As these sustainable landscape development methods evolve, improved maintenance cost savings and public acceptance is anticipated.