Herrera Environmental Consultants Inc.

Seattle, WA, United States

Herrera Environmental Consultants Inc.

Seattle, WA, United States
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Knappenberger T.,Auburn University | Jayakaran A.D.,Washington State University | Stark J.D.,Washington State University | Hinman C.H.,Herrera Environmental Consultants Inc.
Journal of Irrigation and Drainage Engineering | Year: 2017

Performance of porous asphalt (PA) was evaluated on a parking lot of the Washington State University Puyallup campus that included three pavement treatments in triplicate: maintained impervious asphalt (MIA), maintained porous asphalt (MPA), and unmaintained porous asphalt (UPA). Maintained treatments were annually swept with a regenerative air street sweeper. Infiltration rates measured annually using an infiltration ring declined over the course of the study (2011-2015) from 118 to 39 mm/min for the MPA, and from 134 to 54 mm/min for UPA, respectively. Lower infiltration rates on maintained cells relative to unmaintained cells are ascribed to the air-blast and suction cycle that characterizes the type of street sweeper used. The authors hypothesize that particulate matter was forced deeper into the porous structure of the pavement wearing course, reducing infiltration rates in the maintained cells. Annual maintenance was shown to be too infrequent and did not prevent infiltration rates from declining, with parts of the pavement cells becoming clogged. However, performance of the pavement as a whole, measured by relating total storm inflow to storm outflow, did not decline over the study period with 99.5% of storm inflow infiltrating into the porous asphalt pavement surface. Time-series analysis showed that peak flow mitigation of stormwater was considerably superior with permeable pavements in comparison with impervious pavement surfaces. ©2017 American Society of Civil Engineers.

Skaugset A.,Oregon State University | Surfleet C.,Oregon State University | Meadows M.,University of the Sierra | Amann J.,Herrera Environmental Consultants Inc.
Transportation Research Record | Year: 2011

Forest roads can be a source of accelerated erosion, which can be detrimental to aquatic habitat, fish, and other aquatic biota. Erosion models are increasingly used to quantify sediment production from forest roads. This project evaluated the efficacy of these models to predict erosion from forest roads. Sediment production was measured from 44 road segments in the humid, temperate rain forests of Oregon and California. Sediment production from these road segments was estimated with four contemporary erosion models: the Washington Road Surface Erosion Model (WARSEM); Sediment Model 2 (SEDMODL2); WEPP: Road, an interface for the Water Erosion Prediction Project Model; and the revised universal soil loss equation (RUSLE). The erosion models consistently overestimated the amount of sediment produced by the road segments by 2 to 8 times. The results were highly variable, and there were considerable differences in erosion estimated by the four models, even for the same road segment. Further, the erosion models could not consistently identify the road segments that were the top sediment producers. It is hypothesized that the regionalized parameters used as inputs for the models do not adequately characterize the hydrology of the individual road segments. In the humid, temperate rain forests of the Pacific Northwest, surface erosion from forest roads is best predicted by the amount of runoff from the road during storms. Thus, research that will better quantify the hydrology of forest roads will provide better information to predict surface erosion from forest roads.

Major J.J.,U.S. Geological Survey | O'Connor J.E.,U.S. Geological Survey | Podolak C.J.,Johns Hopkins University | Keith M.K.,U.S. Geological Survey | And 9 more authors.
US Geological Survey Professional Paper | Year: 2012

The October 2007 breaching of a temporary cofferdam constructed during removal of the 15-meter (m)-tall Marmot Dam on the Sandy River, Oregon, triggered a rapid sequence of fluvial responses as ∼730,000 cubic meters (m3) of sand and gravel filling the former reservoir became available to a high-gradient river. Using direct measurements of sediment transport, photogrammetry, airborne light detection and ranging (lidar) surveys, and, between transport events, repeat ground surveys of the reservoir reach and channel downstream, we monitored the erosion, transport, and deposition of this sediment in the hours, days, and months following breaching of the cofferdam.

Fontaine M.M.,Herrera Environmental Consultants Inc. | Steinemann A.C.,University of California at San Diego | Steinemann A.C.,University of Colorado at Boulder | Hayes M.J.,University of Nebraska - Lincoln
Natural Hazards Review | Year: 2014

Drought preparedness programs are considered a primary defense against drought hazards. This article investigates state drought programs in the western United States, including a review of drought plans and interviews with state drought officials. While nearly all states have developed drought plans and larger drought programs, the scope and depth of these programs vary widely. State programs and plans typically address monitoring, declaration and response, and communication and coordination. Yet few states conduct postdrought assessments or impact and risk assessments. Resources tend to be allocated more for drought response than mitigation. Officials emphasized not only the importance of available monitoring data, but also the need for improved information for monitoring and predicting drought. State drought officials recommended the following: (1) clear and relevant drought indicators and triggers; (2) frequent communication and coordination among state agencies, local governments, and stakeholders; (3) regularly updated drought plans; and (4) strong leadership that includes a full-time state drought coordinator. © 2014 American Society of Civil Engineers.

Lancaster A.,Herrera Environmental Consultants Inc.
Low Impact Development 2010: Redefining Water in the City - Proceedings of the 2010 International Low Impact Development Conference | Year: 2010

As a part of the new NDPES permit requirements, the Washington State Department of Ecology has introduced flow duration standards for creek protection that require the use of continuous simulation hydrologic modeling. The new permit also requires the use of low impact development (LID) best management practices (BMPs) to the maximum extent feasible. To address these complex regulations, a tool was developed to simplify the sizing of pre-designed LID BMPs for jurisdictions in western Washington. This tool allows the designer to size BMPs without extensive calculations or continuous modeling, and can streamline agency review of design submittals by providing "rule of thumb" sizing equations. By providing pre-designed and pre-sized LID BMPs, this tool helps reduce barriers to LID implementation in western Washington. This paper presents the modeling methods and resulting LID BMP sizing tool for Kitsap County, Washington. Similar methods will be used in 2010 and 2011 for a grant-funded effort to develop a regional tool for all lowland areas in western Washington. © 2010 ASCE.

Kirschbaum R.,Herrera Environmental Consultants Inc. | Spencer B.,Seattle Public Utilities
Low Impact Development 2010: Redefining Water in the City - Proceedings of the 2010 International Low Impact Development Conference | Year: 2010

Like many cities in the United States, a large portion of Seattle's underground drainage pipe networks consist of combined stormwater/sewer systems that were designed to convey both sewage and rainfall runoff from paved surfaces, such as rooftops and roadways. These systems were not designed with adequate capacity for the demands placed on them today. With population and development in Seattle already beyond the designed system capacity in many areas, the combined sewer systems are frequently overwhelmed during large rain storms, resulting in combined sewer overflows (CSOs) into local lakes and Puget Sound. Seattle Public Utilities (SPU) is investigating various strategies for controlling these CSO events. Traditionally, large centralized detention facilities have been used to store high flow volumes during the peak of a storm, which are then released back to the system after the storm has subsided. Currently SPU is conducting a pilot project in the Lakewood neighborhood to evaluate the use of decentralized (customer-based) strategies for reducing CSOs to Lake Washington. These strategies include rain gardens and cisterns installed on single family residential sites to capture and control rainwater on-site. Hydrologic and hydraulic modeling performed for this project using InfoWorks Collection System (CS) and Western Washington Hydrology Model (WWHM) indicate that the pilot project alone would not achieve the regulatory goal of one CSO event per year in the basin. However, widespread use of cisterns and rain gardens by Lakewood residents could significantly reduce the required volume of other traditional CSO infrastructure by as much as 25 percent. This paper documents the development and evaluation of alternatives for decentralized strategy pilot studies in the Lakewood neighborhood of Seattle, Washington. To support alternative development, an array of decentralized strategies was evaluated for CSO reduction benefits, as well as potential water quality impacts to Lake Washington. © 2010 ASCE.

Doberstein C.,Herrera Environmental Consultants Inc. | Kirschbaum R.,Herrera Environmental Consultants Inc. | Lancaster A.,Herrera Environmental Consultants Inc.
Low Impact Development 2010: Redefining Water in the City - Proceedings of the 2010 International Low Impact Development Conference | Year: 2010

Low impact development (LID) - design that strives to mimic natural hydrologic processes - continues to grow and evolve as a preferred method of stormwater management. Agencies and jurisdictions across the nation are working to facilitate and promote incorporation of LID approaches into surface water management programs. Key to these efforts is the need to identify and address barriers that impede LID implementation at the local and regional level. Stormwater practitioners in the Pacific Northwest have been at the forefront of technical and policy developments in LID, including direct efforts to identify and remove barriers to widespread implementation. This paper addresses key barriers identified in the state of Washington, their impact, and the steps being taken by local agencies, institutions, and professionals to remove them. The barriers are: 1. Insufficient designer and policymaker familiarity with LID applications and limitations 2. Stormwater regulations lagging behind field performance data 3. Skepticism about LID facility performance and reliability 4. Technical complexity, particularly for parcel/SFR-scale applications 5. Homeowner acceptance, understanding, and willingness to maintain facilities 6. Water rights-related limitations. © 2010 ASCE.

Wadzuk B.M.,Villanova University | Schneider D.,Villanova University | Schneider D.,University of Colorado at Boulder | Feller M.,Villanova University | And 2 more authors.
Journal of Irrigation and Drainage Engineering | Year: 2013

The ability to estimate the components of the hydrologic cycle is the key to the proper design and implementation of storm-water control measures (SCMs). Reuse, infiltration, and evapotranspiration (ET) are used by SCMs to reduce runoff. This study quantifies the ET component of a green-roof SCM water budget using weighing lysimeters for 3 years demonstrating its significance. Each of the years (2009-2011) was different climatologically. The measured ET was compared with potential ET calculated by several methods. Further, the measured ET is analyzed for its dependency on climatological factors and previous rain day. The average daily ETwas observed to range from 1 to 10 mm/day depending on season, temperature, relative humidity, solar radiation, and antecedent moisture condition. © 2013 American Society of Civil Engineers.

Ballek L.J.,Herrera Environmental Consultants Inc. | Dunlap S.,Atlantic Richfield Company
28th Annual Meeting of the American Society of Mining and Reclamation 2011 | Year: 2011

The Opportunity Ponds Wetlands project is a 2.2 km 2 (544 acre) manmade wetland located 5 km (2.4 miles) east of Anaconda, Montana. A 0.9 km 2 (222 acre) area of wetland was planted in 2009, and a 0.65-km 2 (161 acre) area was planted in 2010. Careful design, excavation, site shaping, and diligent quality assurance have resulted in exceptional plant establishment. The area west of the wetland site was used as a repository for tailings from the smelting of copper ore. Remediation of the repository includes capping the tailings with soil material obtained from nearby borrow areas. The Opportunity Ponds Wetlands are being developed on depleted borrow areas. The goal of the Opportunity Ponds Wetlands revegetation is to create functional vegetation communities that reflect natural wetland habitats. Revegetation plans correlate to the topography and hydrology that have been established. Plants utilized are species observed within native wetland areas close to the site, and plant communities are arranged in "planting zones". Seed for plant production is collected locally and plants are grown under contract by a native plant nursery. Stringent specifications for plant production and placement were developed with EPA oversight. Planting and maintenance activities continue at the site, with final planting to be concluded in 2011. The survival of the 2009 and 2010 plantings has been very good and the water fowl and wildlife use is increasing. Preliminary monitoring results indicate that this project will achieve the goals of providing valuable cover material and creating valuable wetlands for habitat and mitigation.

Fleming A.,Herrera Environmental Consultants Inc. | Stutes J.,Marine Ecologist
Pipelines 2011: A Sound Conduit for Sharing Solutions - Proceedings of the Pipelines 2011 Conference | Year: 2011

In 2004, our design team began a four-year project with the City of Bellingham, Washington (City) to design, permit, and construct a replacement for the City's Alternative Outfall. The Alternative Outfall serves as a second outfall for the Post Point Wastewater Treatment Plant (WWTP) when peak flows exceed the capacity of the 1520 mm (60-inch) Primary Outfall. The old 760 mm (30-inch) diameter Alternative Outfall was undersized, had numerous joint failures, and the end of the 150 meter (500 ft) long outfall had become aspirated with sediment due to extended periods of no flow. The design team developed several options to repair the pipeline, including sliplining, pipe ramming, and replacement with a larger pipeline. After careful evaluation, the City decided to replace the existing pipeline with a stronger, higher capacity 1400 mm (54-inch) diameter pipeline outfall protruding farther from the shoreline into Bellingham Bay. To minimize ecological impacts to a large and very healthy eelgrass (Zostera marina) bed, the outfall alignment was shifted to pass through a thinner section of the eelgrass, reducing overall impact. The project team also developed an extensive eelgrass mitigation plan for this alignment. The design team worked closely with the Washington Department of Fish and Wildlife and the Washington State Department of Natural Resources to implement several innovative procedures to aid in eelgrass mitigation, including an experimental clamshell dredge removal method and the first large-scale use on the western U.S. coast of the Transplanting Eelgrass Remotely with Frames (TERFs; developed by Short et al. [2002]) methodology. Divers were also deployed to remove and transplant eelgrass using more traditional methods. During construction, difficulties were encountered sinking the pipeline, sealing the 1400 mm (54-inch) rubber check valve, and stabilizing the marine backfill. This paper discusses some of the design considerations, construction challenges, the lessons learned in working in a sensitive marine environment, and the preliminary results of the experimental eelgrass transplanting methods. © 2011 ASCE.

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