Riparian seasonal water quality and greenhouse gas dynamics following stream restoration

Recent ecological stream restoration projects have focused on expanding the water-friendly space of streams, promoting the health of aquatic ecosystems, and restoring various habitats, which raise the need for relevant research. Applying integrated environmental analysis, this study quantifies the change in hydraulic characteristics before and after the restoration projects through physical habitat simulation and links the results of physical impacts to estimate benefits of increase in water quality and aquatic ecosystem health due to the implementation of the project. For this, the study area is a 3.3 km long reach of the Anyang-cheon Stream, Korea. Field monitoring revealed that five fish species are dominant and sub-dominant, and account for 76% of the total fish community. To assess the change of before and after ecological stream restoration project, the River2D and Coastal Modelling System (CMS)-Flow 2D models were used for hydraulic and water quality simulations, respectively. For the habitat simulation, the HSI (Habitat Suitability Index) model was used. In addition, the Canadian Council of Ministers of the Environment Water Quality Index (CCME WQI) was used to calculate changes in water quality index and to examine changes in habitat areas with an integrated quantitative index, the methodology of Zingraff-Hamed et al. was adopted. It was found that the ecological stream restoration project significantly increased for the eco-friendly area. In addition, the changes in water quality and habitat suitability grades before the ecological river restoration project were improved to two stages and one stage, respectively. This study applied the integrated analytical framework as a policy/project assessment tool and the results of this study will be useful for the integrated water management policy.

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Stream Restoration for Legacy Sediments at Gramies Run, Maryland: Early Lessons from Implementation, Water Quality Monitoring, and Soil Health

Water ◽

10.3390/w12082164 ◽

2020 ◽

Vol 12 (8) ◽

pp. 2164

Author(s):

Katie Mattern ◽

Alyssa Lutgen ◽

Nathan Sienkiewicz ◽

Grant Jiang ◽

Jinjun Kan ◽

...

Keyword(s):

Water Quality ◽

Riparian Vegetation ◽

Stream Restoration ◽

Soil Health ◽

Water Quality Monitoring ◽

Quality Monitoring ◽

Nutrient Inputs ◽

Nitrogen And Phosphorus ◽

Partial Removal ◽

Riparian Trees

While stream restorations are increasingly being adopted to mitigate sediment and nutrient inputs and to meet water quality regulatory targets, less information is available on the drivers behind the design, implementation, effectiveness, and cost of restorations. We address these issues for a $4.2 million stream restoration for legacy sediments implemented for a rural Piedmont stream in Maryland, USA. A total of 1668 m of stream was restored in three phases, which included the partial removal of legacy sediments, the grading of streambanks, floodplain creation, channel reshaping with meanders and pool-riffle forms, the raising of the stream bed, and the planting of riparian vegetation. The sediment, nitrogen, and phosphorus concentrations and fluxes were monitored before- and during the restoration phases. The sites selected for restoration had legacy sediments vulnerable to erosion and were on state-owned land. The restoration design was based on the need to maintain mature riparian trees and preserve existing sensitive wetland habitats. Water quality monitoring indicated that the sediment and nutrient fluxes increased during the restoration phase and were attributed to disturbance associated with construction activities and increased runoff. We also recommend that soil health needs to be included as an integral component to enhance the effectiveness and resilience of stream restorations.

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