Lisa Hauck Stream Restoration May 8 2006 The Effects of Stream Restoration on Habitat Quality Lisa Hauck Abstract Many stream restoration projects do not include a requirement for long term monitoring after the project has been completed resulting in a lack of information about the success or failures of certain restoration techniques This study examines habitat quality of four urban streams Wildcat Creek Baxter Creek Alhambra Creek and Peralta Creek in the East Bay region of California before and after restoration to determine the success of the project The studied streams were restored between one and six years ago using a variety of restoration techniques Habitat quality was assessed in restored reaches of streams using the U S Environmental Protection Agency s Rapid Bio assessment Protocols and compared with information about and photographs of the stream before it was restored Results of this study showed that while some aspects of habitat quality were improved at the studied sites not all aspects of the restoration projects were successful in all cases This study shows the importance of performing long term monitoring after the completion of a restoration project Monitoring can reveal whether or not habitat quality has improved whether or not the goals of the project have been met and guide ongoing restoration efforts p 1 Lisa Hauck Stream Restoration May 8 2006 Introduction As society has become more aware of and more concerned about our impact on the environment the idea that people need to minimize their effect on their surroundings has become more popular One way to reduce or counteract the impact we have on the environment is to perform restoration projects in a degraded area such as a stream Stream restorations have been performed for a variety of reasons including economic improvement aesthetic improvement recreational improvement and habitat improvement It has been found that habitat restorations are not always successful in improving species populations in streams and it can often take multiple projects to detect a significant increase in the density of target organisms House 1996 When a lot of money is put into a large scale project such as restoring a stream it is especially important that results are monitored to ensure that goals have been achieved Kondolf and Micheli 1995 note that post restoration monitoring is extremely important in such a project and recommend a decade long monitoring program that also takes into account the historical conditions of the stream Long term monitoring is important because the conditions of a stream immediately after restoration do not always indicate what conditions of the stream will be like in the future Korsu 2004 While restoration projects often have a goal of increasing the abundance of stream life the effect on populations is rarely monitored Because natural processes of a stream such as increased flow during the rainy season can often interfere with improvements made during restoration and counteract the benefits it is essential to monitor the success of the project in increasing stream life Moerke and Lamberti 2003 Determining that a natural process is contributing to the decreasing life in a stream can lead to the enactment of a new restoration that will help keep high population numbers over time While the importance of monitoring a restoration project over a period of time has been shown it does not often occur A survey of select Washington streams reported that only 18 of restoration projects mandate long term monitoring Additionally only six of nine government projects had a requirement for monitoring Bash and Ryan 2002 Restoration projects meant to improve water and habitat quality are especially important to monitor as their results can help to determine whether or not certain techniques are successful Davis et al 2003 found that most stream restorations that have a goal of improving ecological conditions do not even monitor to see if these conditions are actually achieved In order for a p 2 Lisa Hauck Stream Restoration May 8 2006 restoration project to be successful knowledge of how outside variables affect the stream is required Bohn and Kershner 2002 When a restored stream is monitored over an extended period of time it can be determined which factors have the biggest impact on a stream This information will allow for the evaluation of which restorative techniques produce the most success in achieving the goals of the project Future projects will then be able to use the techniques that are most efficient and achieve the more successful results Roni et al 2002 There are many factors that can be monitored to determine the level of success that a restoration project has Determining what factors should be measured generally depends on the goals of the restoration project Shields et al 2003 studied a stream that had been restored to increase fish population Their monitoring took into account the number of fish present in the stream as well as the quality of the habitat they had This study was able to evaluate the success of the project based on the initial goals Restoration projects often have a goal of returning a stream its natural conditions Nijboer 2004 studied the presence of Agapetus fuscipes Trichoptera Glossomatidae in restored streams Agapetus fuscipes is an indicator of natural conditions and can therefore show how successful a restoration project has been at recreating this The long term monitoring of this project revealed that water quality improvement is a major factor in restoring the natural conditions of a stream The United States Environmental Protection Agency has a standardized way to analyze habitat quality based on Rapid Bioassessment protocols This protocol analyzes a variety of habitat parameters and gives each a number score between 0 and 20 Parameters include th amount of native vegetation percent cover and substrate all of which give an indication of the quality of habitat of a stream Addition of all the scores for each factor gives an overall number for each site with a higher score indicating a higher quality habitat This allows for comparison between sites and using this protocol is especially beneficial because it is the standard method for analyzing habitat quality throughout the nation Purcell 2002 allowing results to be compared to comparable studies This project will study four restored streams in the East Bay region of California based on these protocols Habitat assessments
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