Case study:La Gotera dam removal
Project overview
Status | Complete |
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Project web site | |
Themes | Environmental flows and water resources, Habitat and biodiversity, Hydropower, Hydromorphology |
Country | Spain |
Main contact forename | Rincón Sanz |
Main contact surname | Gonzalo |
Main contact user ID | |
Contact organisation | Duero River Basin District |
Contact organisation web site | |
Partner organisations | |
Parent multi-site project | |
This is a parent project encompassing the following projects |
No |
Project summary
The Works of removal started in September 2011 by the Duero River Basin District and
within the framework of the National Strategy of River Restoration (NSRR).
The slope between the river and the banks required the construction of a ramp so that the machines could access to the river. Due to the impossibility of removing the material from the ramp once the work was finished, material from other restoration activities in other river reaches was used. The native vegetation of the area was respected during the works of removal. In addition, it will serve to fix the ramp that allows the approach of the machines to the river.
Prior to the removal, a capture of the fish specimens located upstream of the dam was performed and subsequently released in the same river away from the intervention. A high abundance of fish was observed.
A volume of 1,068 m3 of debris was removed during the works. The concrete from the bypass channel and the dam was removed in the last phase of the work. All elements that are strange to the river like the concrete or metallic remains were removed from the river and moved to authorized dump sites.
With this removal, 15 kilometers of river that previously were interrupted by the dam has been reconnected. Barely a month after the removal of the obstacle, the river has recovered its natural course
Monitoring surveys and results
The information regarding the monitoring of La Gotera dam removal is very scarce. A
study was carried out prior to the demolition of the dam and another one a year later.
Three points were sampled: a reference point upstream the dam, other near the dam
wall and a third one downstream the dam. The fish samplings yielded no significant
results. However, all macroinvertebrate indices did show an improvement, especially
in the sampling point downstream of the dam.
Lessons learnt
The removal of this dam is an example that the performance of these actions, together
with the availability of an adequate flow, generates good results in a short period of
time.
It will be the river with its high flows that finally does the restoration work. The river mobilizes the sediments naturally the year after the removal
Image gallery
Catchment and subcatchment
Site
Project background
Cost for project phases
Reasons for river restoration
Measures
MonitoringHydromorphological quality elements
Biological quality elements
Physico-chemical quality elements
Any other monitoring, e.g. social, economic
Monitoring documents
Additional documents and videos
Additional links and references
Supplementary InformationEdit Supplementary Information References Headwaters Economics (2016). Dam removal: case studies on the Fiscal, Economic, Social and Environmental benefits of dam removal. Industrial Economics Inc. (2015). Economic & Community Benefits from Stream Barrier Removal Projects in Massachusetts (MA). Massachusetts Department of Fish and Game, Division of Ecological Restoration. Ollero Ojeda, A. (2015). Guía metodológica sobre buenas prácticas en restauración fluvial. Manual para gestores. Rodríguez Muñoz, I., Santillán Ibáñez, JI., Huertas, R. (2011). Excursión del I Congreso Ibérico de Restauración de Ríos. León.
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