Lisa Hauck Stream Restoration May 8 2006p. 1The Effects of Stream Restoration on Habitat QualityLisa HauckAbstract Many stream restoration projects do not include a requirement for long-termmonitoring after the project has been completed, resulting in a lack of information about thesuccess or failures of certain restoration techniques. This study examines habitat quality of foururban streams – Wildcat Creek, Baxter Creek, Alhambra Creek and Peralta Creek – in the EastBay region of California before and after restoration to determine the success of the project. Thestudied streams were restored between one and six years ago using a variety of restorationtechniques. Habitat quality was assessed in restored reaches of streams using the U.S.Environmental Protection Agency’s Rapid Bio-assessment Protocols and compared withinformation about, and photographs of, the stream before it was restored. Results of this studyshowed that while some aspects of habitat quality were improved at the studied sites, not allaspects of the restoration projects were successful in all cases. This study shows the importanceof performing long-term monitoring after the completion of a restoration project. Monitoringcan reveal whether or not habitat quality has improved, whether or not the goals of the projecthave been met and guide ongoing restoration efforts.Lisa Hauck Stream Restoration May 8 2006p. 2IntroductionAs society has become more aware of, and more concerned about, our impact on theenvironment, the idea that people need to minimize their effect on their surroundings has becomemore popular. One way to reduce, or counteract the impact we have on the environment is toperform restoration projects in a degraded area, such as a stream. Stream restorations have beenperformed 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 speciespopulations in streams, and it can often take multiple projects to detect a significant increase inthe density of target organisms (House 1996). When a lot of money is put into a large-scaleproject, such as restoring a stream, it is especially important that results are monitored to ensurethat goals have been achieved. Kondolf and Micheli (1995) note that post-restoration monitoringis extremely important in such a project, and recommend a decade-long monitoring program thatalso takes into account the historical conditions of the stream. Long-term monitoring isimportant because the conditions of a stream immediately after restoration do not always indicatewhat 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, theeffect on populations is rarely monitored. Because natural processes of a stream, such asincreased flow during the rainy season, can often interfere with improvements made duringrestoration and counteract the benefits, it is essential to monitor the success of the project inincreasing stream life (Moerke and Lamberti 2003). Determining that a natural process iscontributing to the decreasing life in a stream can lead to the enactment of a new restoration thatwill help keep high population numbers over time.While the importance of monitoring a restoration project over a period of time has beenshown, it does not often occur. A survey of select Washington streams reported that only 18% ofrestoration projects mandate long-term monitoring. Additionally, only six of nine governmentprojects had a requirement for monitoring (Bash and Ryan 2002).Restoration projects meant to improve water and habitat quality are especially important tomonitor 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 ecologicalconditions do not even monitor to see if these conditions are actually achieved. In order for aLisa Hauck Stream Restoration May 8 2006p. 3restoration project to be successful, knowledge of how outside variables affect the stream isrequired (Bohn and Kershner 2002). When a restored stream is monitored over an extendedperiod of time, it can be determined which factors have the biggest impact on a stream. Thisinformation will allow for the evaluation of which restorative techniques produce the mostsuccess in achieving the goals of the project. Future projects will then be able to use thetechniques 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 arestoration project has. Determining what factors should be measured generally depends on thegoals of the restoration project. Shields et al. (2003) studied a stream that had been restored toincrease fish population. Their monitoring took into account the number of fish present in thestream as well as the quality of the habitat they had. This study was able to evaluate the successof 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 restoredstreams. Agapetus fuscipes is an indicator of natural conditions, and can therefore show howsuccessful a restoration project has been at recreating this. The long-term monitoring of thisproject revealed that water quality improvement is a major factor in restoring the naturalconditions of a stream.The United States Environmental Protection Agency has a standardized way to analyzehabitat quality based on Rapid Bioassessment protocols. This protocol analyzes a variety ofhabitat parameters and gives each a number score between 0 and 20. Parameters include thamount of native vegetation, percent cover, and substrate, all of which give an indication of thequality of habitat of a stream. Addition of all the scores for each factor gives an overall numberfor each site, with a higher score indicating a higher quality habitat. This allows for comparisonbetween sites, and using this protocol is especially beneficial because it is the standard methodfor analyzing habitat quality throughout the nation (Purcell 2002), allowing results to becompared to comparable studies.This project will study four restored streams in the
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