skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Managing Floods and Resources at the Arroyo Las Positas

Abstract

Engineers and water resource professionals are challenged with protecting facilities from flood events within environmental resource protection, regulatory, and economic constraints. One case in point is the Arroyo Las Positas (ALP), an intermittent stream that traverses the Lawrence Livermore National Laboratory (LLNL) in Livermore, California. Increased runoff from post-drought rainfall, upstream development, and new perennial discharges from LLNL activities have resulted in increased dry weather flows and wetland vegetation. These new conditions have recently begun to provide improved habitat for the federally threatened California red-legged frog (Rana aurora draytonii; CRLF), but the additional vegetation diminishes the channel's drainage capacity and increases flood risk. When LLNL proposed to re-grade the channel to reestablish the 100-year flood capacity, traditional dredging practices were no longer being advocated by environmental regulatory agencies. LLNL therefore designed a desilting maintenance plan to protect LLNL facility areas from flooding, while minimizing impacts to wetland resources and habitat. The result was a combination of structural upland improvements and the ALP Five Year Maintenance Plan (Maintenance Plan), which includes phased desilting in segments so that the entire ALP is desilted after five years. A unique feature of the Maintenance Plan is the variable length of the segments designed tomore » minimize LLNL's impact on CRLF movement. State and federal permits also added monitoring requirements and additional constraints on desilting activities. Two years into the Maintenance Plan, LLNL is examining the lessons learned on the cost-effectiveness of these maintenance measures and restrictions and reevaluating the direction of future maintenance activities.« less

Authors:
; ;
Publication Date:
Research Org.:
Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
15013477
Report Number(s):
UCRL-JC-147519
TRN: US200601%%421
DOE Contract Number:  
W-7405-ENG-48
Resource Type:
Conference
Resource Relation:
Conference: 2002 Water Resources Planning & Management Conference, Roanoke, VA, May 19 - May 22, 2002
Country of Publication:
United States
Language:
English
Subject:
54 ENVIRONMENTAL SCIENCES; CAPACITY; DRAINAGE; DREDGING; ENGINEERS; FLOODS; FROGS; HABITAT; MAINTENANCE; MANAGEMENT; MONITORING; PLANNING; PLANTS; RUNOFF; WATER RESOURCES; WEATHER; WETLANDS

Citation Formats

Sanchez, L, Van Hattem, M, and Mathews, S. Managing Floods and Resources at the Arroyo Las Positas. United States: N. p., 2002. Web.
Sanchez, L, Van Hattem, M, & Mathews, S. Managing Floods and Resources at the Arroyo Las Positas. United States.
Sanchez, L, Van Hattem, M, and Mathews, S. 2002. "Managing Floods and Resources at the Arroyo Las Positas". United States. https://www.osti.gov/servlets/purl/15013477.
@article{osti_15013477,
title = {Managing Floods and Resources at the Arroyo Las Positas},
author = {Sanchez, L and Van Hattem, M and Mathews, S},
abstractNote = {Engineers and water resource professionals are challenged with protecting facilities from flood events within environmental resource protection, regulatory, and economic constraints. One case in point is the Arroyo Las Positas (ALP), an intermittent stream that traverses the Lawrence Livermore National Laboratory (LLNL) in Livermore, California. Increased runoff from post-drought rainfall, upstream development, and new perennial discharges from LLNL activities have resulted in increased dry weather flows and wetland vegetation. These new conditions have recently begun to provide improved habitat for the federally threatened California red-legged frog (Rana aurora draytonii; CRLF), but the additional vegetation diminishes the channel's drainage capacity and increases flood risk. When LLNL proposed to re-grade the channel to reestablish the 100-year flood capacity, traditional dredging practices were no longer being advocated by environmental regulatory agencies. LLNL therefore designed a desilting maintenance plan to protect LLNL facility areas from flooding, while minimizing impacts to wetland resources and habitat. The result was a combination of structural upland improvements and the ALP Five Year Maintenance Plan (Maintenance Plan), which includes phased desilting in segments so that the entire ALP is desilted after five years. A unique feature of the Maintenance Plan is the variable length of the segments designed to minimize LLNL's impact on CRLF movement. State and federal permits also added monitoring requirements and additional constraints on desilting activities. Two years into the Maintenance Plan, LLNL is examining the lessons learned on the cost-effectiveness of these maintenance measures and restrictions and reevaluating the direction of future maintenance activities.},
doi = {},
url = {https://www.osti.gov/biblio/15013477}, journal = {},
number = ,
volume = ,
place = {United States},
year = {Tue Mar 05 00:00:00 EST 2002},
month = {Tue Mar 05 00:00:00 EST 2002}
}

Conference:
Other availability
Please see Document Availability for additional information on obtaining the full-text document. Library patrons may search WorldCat to identify libraries that hold this conference proceeding.

Save / Share: