Restoration Challenges Research Articles

Restoration of urban salt marshes: Lessons from southern California

Extensive restoration efforts in southern California coastal wetlands highlight several challenges for urban salt marsh restoration, including: habitat isolation and fragmentation, impacts from exotic species, the loss of transitional upland habitats, and other alterations to hydrologic and sediment dynamics. Habitat isolation impairs colonization by dispersal-limited plants, so planting becomes essential to achieve diverse salt marshes. Low species richness slows the development of salt marsh functions (e.g., biomass and nitrogen accumulation) in southern California. A variety of exotic species have invaded the upper reaches of salt marshes in southern California, most commonly in marshes with hydrological modifications. The replacement of gradual slopes between wetlands and uplands by sharp transitions abutting urban development limits our ability to restore rare plant and animal populations. Where hydrologic connections are impaired by roads and other structures, the natural migration of channels is constrained, and sediment dynamics often lead to lagoon mouth closure. A case study from Tijuana River National Estuarine Research Reserve (hereafter, Tijuana Estuary) further illustrates a specific lesson for urban salt marsh restoration concerning watershed issues and sediment dynamics. In the south arm of Tijuana Estuary, watershed urbanization, along with local climate, topography, and soils, has resulted in extreme rates of sediment accumulation. Sedimentation rates in a salt marsh in the south arm of the estuary ranged from 10 to 30 cm over a single winter (1994–95), substantially greater than historic sedimentation rates in the estuary or rates from other coastal wetlands with storm sedimentation. Sediment buried salt marsh vegetation in place and is converting intertidal salt marsh to uplands. These impacts illustrate the need to consider watershed issues and sediment control in managing and restoring urban salt marshes.

Eliza's changing face: a restoration challenge in WA

Eliza's changing face: a restoration challenge in WA

Natural resource trustee partnering in the urban river restoration initiative

AbstractMany urban rivers in the United States contain severely contaminated sediments that adversely affect aquatic life and limit recreational and economic uses. The U.S. Environmental Protection Agency (EPA) estimated in 1997 that more than 1.2 billion cubic yards of contaminated sediment exist nationwide. In response to this situation, a new interagency cooperative program to restore rivers affected by contaminated sediments is being undertaken. This program, called the Urban River Restoration Initiative, offers a new opportunity for natural resource trustee agencies to address problems on a watershed basis in partnership with other federal, state, and local entities.On July 2, 2002, the U.S. Army Corps of Engineers (Corps) and EPA signed a Memorandum of Understanding (MOU) entitled “Restoration of Degraded Urban Rivers” to coordinate remedial, water quality, and environmental restoration activities under the Clean Water Act, Comprehensive Environmental Response, Compensation, and Liability Act, Resource Conservation and Recovery Act, and the Water Resources Development Acts. The MOU calls for the identification of eight pilot projects to be announced and undertaken within one year of the date of the MOU.The principal Federal natural resource trustee agencies (Interior and the National Oceanic and Atmospheric Administration [NOAA]) are likely to be heavily involved with the Corps, EPA, and state and local agencies in preparing comprehensive, watershed‐based plans for the eight pilot projects, and in undertaking such plans. A model for such partnering already is evolving in the Passaic River, New Jersey, watershed, where a cooperative study currently is being planned for a project that is likely to be named as one of the eight pilots. The Passaic River, located in the heartland of the U.S. industrial revolution, is one of the most complex riverine restoration challenges in the nation. The Passaic River Restoration Initiative, as the project is called, involves a partnership among four Federal and two state agencies. These are Interior, NOAA, the Corps, EPA, the New Jersey Department of Environmental Protection and the New Jersey Office of Maritime Resources. The U.S. Fish and Wildlife Service has been designated as the administrative trustee for the effort. © 2004 Wiley Periodicals, Inc.

Challenges of Restoration

Challenges of Restoration

Everglades Restoration: Interactions of Population and Environment

The Everglades system has suffered drastic changes to its life-blood, water. Dramatic population increases and intensive drainage efforts have significantly altered water quantity, quality, timing, and distribution through the system. This paper reviews water management alterations to the Everglades system and changes in the region's population and demography documenting the interconnectivity of the human and natural system. Specific ramifications of population and economic growth on land use, water use, and flood control are examined as a backdrop for discussion of the Comprehensive Everglades Restoration efforts now underway. Through discussion of these ramifications and restoration efforts, challenges and opportunities for successful Everglades restoration are identified.

Post-project appraisals in adaptive management of river channel restoration.

Post-project appraisals (PPAs) can evaluate river restoration schemes in relation to their compliance with design, their short-term performance attainment, and their longer-term geomorphological compatibility with the catchment hydrology and sediment transport processes. PPAs provide the basis for communicating the results of one restoration scheme to another, thereby improving future restoration designs. They also supply essential performance feedback needed for adaptive management, in which management actions are treated as experiments. PPAs allow river restoration success to be defined both in terms of the scheme attaining its performance objectives and in providing a significant learning experience. Different levels of investment in PPA, in terms of pre-project data and follow-up information, bring with them different degrees of understanding and tbus different abilities to gauge both types of success. We present four case studies to illustrate how the commitment to PPA has determined the understanding achieved in each case. In Moore's Gulch (California, USA), understanding was severely constrained by the lack of pre-project data and post-implementation monitoring. Pre-project data existed for the Kitswell Brook (Hertfordshire, UK), but the monitoring consisted only of one site visit and thus the understanding achieved is related primarily to design compliance issues. The monitoring undertaken for Deep Run (Maryland, USA) and the River Idle (Nottinghamshire, UK) enabled some understanding of the short-term performance of each scheme. The transferable understanding gained from each case study is used to develop an illustrative five-fold classification of geomorphological PPAs (full, medium-term, short-term, one-shot, and remains) according to their potential as learning experiences. The learning experience is central to adaptive management but rarely articulated in the literature. Here, we gauge the potential via superimposition onto a previous schematic representation of the adaptive management process by Haney and Power (1996). Using PPAs wisely can lead to cutting-edge, complex solutions to river restoration challenges.

Surmounting the engineering challenges of Everglades restoration

The South Florida Water Management District, in partnership with other agencies and stakeholders, is undertaking one of the world's largest ecosystem restoration programs. The foundation of the nutrient control program for the Everglades is a set of six large constructed wetlands, referred to as Stormwater Treatment Areas (STAs). The initial treatment goal is to reduce phosphorus entering the Everglades to 50 parts per billion. The STAs comprise almost 17,000 hectares, with a capital cost of approximately $700 million. Approximately 4,720 hectares are currently operational, another 2,600 hectares are in the start-up phase, and construction is just getting under way on the remaining areas. Throughout the design process, engineers and scientists collaborated to capture the best available information on wetland treatment systems, and to develop the most appropriate design criteria. Some of the more challenging issues included characterizing stormwater inflows and phosphorus loads, determining appropriate nutrient removal performance characteristics, and estimating hydraulic design parameters relating to densely vegetated systems. The design process combined in-house staff with engineering consultants, construction contractors, external review groups and independent peer-review. This paper summarizes major design aspects and key assumptions, and sets the stage for addressing future challenges associated with achieving long-term water quality goals of Everglades restoration.

Biodiversity in Critical Transition Zones between Terrestrial, Freshwater, and Marine Soils and Sediments: Processes, Linkages, and Management Implications

The boundaries between aquatic and terrestrial ecosystems, and particularly the interfaces among soils, freshwater sediments, and marine sediments, are known as “critical transition zones” (CTZs). These interfaces are critically important because they are dynamic habitats that control or influence the movement of organisms, nutrients, materials, and energy within and across landscapes through linked ecosystem processes. They are therefore not only vital to local processes within the transition habitat itself but also have significant effects on adjacent ecosystems. The papers in this volume by Bardgett and others (2001), Levin and others (2001), and Ewel and others (2001) are the results of an international workshop convened by the Committee on Soil and Sediment Biodiversity and Ecosystem Functioning of the Scientific Committee on Problems in the Environment (SCOPE) to address the following topics: (a) biodiversity in the soils and sediments of CTZs, (b) the ecosystem processes that occur within these zones, (c) CTZs as pathways connecting adjacent ecosystems, and (d) the implications for the management for these habitats. Levin and others survey marine interfaces (estuaries, coastal wetlands), whereas Bardgett and others discuss terrestrial interfaces (that is, the zones between land and both fresh and marine waters). Ewel and colleagues offer a consideration of the management and restoration challenges faced by scientists and managers today, with emphasis on the need for greater collaborative efforts by all interested parties. The papers presented here reflect the current thinking on a subset of all existing types of critical transition zones. There are many other types of transition zones that are not covered in this issue (riparian zones, freshwater wetlands, and so on); however, the issues of concern raised by these authors for marine and terrestrial CTZs are analogous. It is our hope that this strict focus on the problems of marine and terrestrial CTZs will serve to stimulate the study of more diverse types of CTZs. It is particularly important that future work address land–water interfaces because of the many urgent environmental problems that are centered there. For example, the recently released National Research Council report Grand Challenges in Environmental Sciences (NRC 2000) cited water resources, land-use dynamics, and biodiversity among its list of the most pressing areas for environmental research today. Of particular concern is our need to understand how changes in the landscape affect water supplies and the flow of sediments to rivers Received 14 March 2001; accepted 16 March 2001. *Corresponding author; e-mail: diana@nrel.colostate.edu Ecosystems (2001) 4: 418–420 DOI: 10.1007/s10021-001-0103-3 ECOSYSTEMS

An improved algorithm to aid in post-heat storm restoration

Utilities strive to have quick restoration after a power outage. Extreme conditions, such as storms, create difficult restoration challenges because of the large number of tasks necessary to restore power to many affected customers. Restoration efforts can be further hindered when outage report escalation algorithms predict the wrong location for affected devices. This paper describes a modified topological based algorithm that associates trouble calls with each other to provide more accurate information about outages during heat storms. The heat storm algorithm was tested and verified on two feeders using test cases that simulated the heat storm conditions experienced at Northern States Power Company in Minneapolis, Minnesota in July 1995.

Inventories, Surveys and Historic Preservation

The civil engineering profession is becoming increasingly involved in technical challenges associated with historic preservation. Inventories, surveys, and recording projects are uncovering more engineering and industrial sites and structures which can be adapted and reconstructed for a variety of uses. National organizations (such as the National Architectural and Engineering Record and the National Trust for Historic Preservation) work with local, state and regional groups in such surveys as well as in adaptive and other commercial studies. The Society for Industrial Archeology and similar organizations provide common meeting grounds for all people interested in such preservation work. Technically, financially, and personally, there are many rewards in meeting the challenges of professional preservation, restoration, rehabilitation, and adaptation.