Evaluating Riparian Buffers for Nonpoint Source Pollution Control in an Urban Setting Using the Riparian Ecosystem Management Model, Remm

Abstract

Environmental planners recognize the importance of maintaining the integrity of a riparian buffer when land is developed for urban purposes. The state of Delaware requires that 60 percent of the P and 40 percent of the N loadings from new urban land developments be reduced before flowing to surface water. Riparian buffers are effective for treatment of urban storm water runoff, but they are frequently designed using non-specific site criteria for agricultural riparian buffers. The objective of this research was to evaluate the Riparian Ecosystem Management Model (REMM) as a tool for designing urban riparian buffers based on site-specific data. REMM inputs were obtained from published literature and REMM databases. N, P and sediment loadings at the buffer edge were input from SWAT model simulations. A three-zone 15 m and a 30 m riparian buffer were simulated. Results were summarized using five rainfall years (minimum, below average, average, above average and maximum) from the 25-year simulation. Total P was reduced by nearly 60 percent for the 15 m buffer except the low rainfall year. Even though the desired minimum was not reached, the total influx was small and the overall outflow was 0.3 kg P ha-1. Based on these simulation results, the Delaware guidelines for buffer size appear to be too large. Currently, Delaware requires a 30 m forested or vegetation zone for developed areas. Results of this study will be beneficial to individuals who are responsible for nonpoint source permitting and for the control of urban storm water runoff.

Riparian buffer effectiveness as a function of buffer design and input loads

“…Users can specify the width, vegetation, and management practice of each buffer zone. The REMM database includes photosynthesis and growth parameters to represent the average vegetative conditions in the northeastern United States (Allison, Fatula, & Wolanski, 2006). Management practice options in REMM include burning, harvesting, mowing, and fertilizing.…”

“…The Pennsylvania Riparian Forest Buffer Handbook for CREP requires a minimum width of 15 m for landowners to be eligible for payment from the state (Noto & Linsenbigler, 2017). The Pennsylvania Stormwater BMP Manual (Pennsylvania Department of Environmental Protection, 2006) suggests a three‐zone buffer system, with Zone 3 composed of natural grass with a minimum width of 6 m, Zone 2 covered by managed forest with a minimum width of 19 m, and Zone 1 containing undisturbed or native forest with a minimum width of 5 m. The forested zones in REMM are represented using the average photosynthesis and growth parameters of native vegetative conditions in the northeastern United States (Allison et al., 2006).…”

Effectiveness of hydrologically upgraded natural vegetation riparian buffer on stream water quality protection at Uyo municipality cattle market/slaughter, Nigeria

“…Design criteria which determine the effectiveness of riparian buffers are many and are as follows: hydrology, buffer width, type of vegetation and management etc. They are valuable parameters for evaluating how riparian buffers effectively control NPS pollution in an urban setting (Allison et al, 2006). The hydrology design enables run-off flow to spread over the buffer sections' floor, preventing the formation of channels and channelized flow.…”