DOCSLIB.ORG

Sediment Discharge in the Upper Arroyo Grande and Santa Rita Creek Basins 23 5

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Sediment Discharge in the Upper Arroyo Grande and Santa Rita Creek Basins 23 5 PB 256 422 Sediment Discharge in the Upper Arroyo Grande and 41,111 anta Rita Creek Basins, tot,:San Luis Obispo County, 1144300,6k California U. S. GEOLOGICAL SURVPFY Water-Resources Investigations 151/4 76-64 101„,14.11kup lemw QE Prepared in cooperation with the 75 .U58w SAN LUIS OBISPO COUNTY no.76-64 1976 ENGINEERING DEPARTMENT lkigtikPHIC DATA I. ReportuNo.Gs 2. 3. Recipient's Accession No. S NRD/WRI-76/053 4. Title and Subtitle 5.keport Date WS14/3610WPOISCHARGE IN THE UPPER ARROYO GRANDE AND SANTA RITA June 1976,/ 6. ben,/ erctFardthf INS, SAN LUIS OBISPO COUNTY, CALIFORNIA (t;"f„ ,, ,/,,,,,,,, °./. Author(s) 8. Performing Organization Rept. .„ J. M. Knott,! N'- USGS/WRI 76-64 9. Performing Organization Name and Address 10. Project/Task/Work Unit No. U.SAeological Survey, Water Resources Division California District )- 11. Contract/Grant No. 345 Middlefield Road Menlo Park, California 94025 12. Sponsoring Organization Name and Address 13. Type of Report & Period U.S. Geological Survey, Water Resources Division Covered California District Final 345 Middlefield Road 14. Menlo Park, California 9409c 15. Supplementary Notes Prepared in cooperation wit igir. .ng Department 16.AbstractsSediment data collected in the upper Arroyo Grande and Santa Rita Creek basins during the 1968-73 water years were analyzed to determine total sediment discharge at four stations in the basins. Water discharge and total sediment discharge at these stations, representative of the 1943-72 period, were estimated from'long-term flow data for nearby gaging stations and water-sediment discharge relations determined for the 1968-73 water years. Most of the total annual sediment discharge at each station occurs during a few days each year. The quantity of sediment transported in a single day often accounts for more than 40 percent of the total annual sediment discharge. Estimated sediment discharge for the upper Arroyo Grande and Santa Rita Creek basins during the 1943-72 water years averaged 53,000 tons (48,000 tonnes) and 23,000 tons (21,000 tonnes) per year. Long-term sediment deposition in Lopez Reservoir, which is in the southern part of the upper Arroyo Grande basin, was estimated to be 35 acre-feet (0.043 cubic hectometres) per year. 17. Key Words and Document Analysis. 17a. Descriptors *Sediment Discharge, Sediment Transport, Bed Load, Suspended Sediment, California 1713. Identifiers/Open-Ended Terms San Luis Obispo County, Lopez Reservoir 17c. COSATI Field /Group 18. Availability Statement 19, Security Class (This 21. No. of Pages Report) UNCLASSIFIED 32 No restriction on distribution 20. Security Class (This 22. Price Page UNCLASSIFIED FORM NTI5-35 (REV. 10-73) ENDORSED BY ANSI AND UNESCO. THIS FORM MAY BE REPRODUCED USCOMM-OC 8265-P74 SEDIMENT DISCHARGE IN THE UPPER ARROYO GRANDE AND SANTA RITA CREEK BASINS, SAN LUIS OBISPO COUNTY, CALIFORNIA By J. M. Knott U.S. GEOLOGICAL SURVEY Water-Resources Investigations 76-64 Prepared in cooperation with the San Luis Obispo County Engineering Department June 1976 UNITED STATES DEPARTMENT OF THE INTERIOR Thomas S. Kleppe, Secretary GEOLOGICAL SURVEY V. E. McKelvey, Director For additional information write to: District Chief Water Resources Division U.S. Geological Survey 345 Middlefield Rd. Menlo Park, Calif. 94025 CONTENTS Page Conversion factors V Abstract 1 Introduction 2 Previous investigations 2 Description of the basins 2 Climate 3 Streamf low 3 Sediment discharge 4 Sediment transport in the basins 4 Data collection 4 Short-term record, 1968-73 6 Estimated bedload discharge, 1968-72 6 Estimated total sediment discharge, 1943-72 6 Selected references 8 Illustrations 11 Tables 21 ILLUSTRATIONS Page Figure 1. Index map showing the location of the study areas 11 2-3. Maps showing selected stream-gaging and sediment-sampling stations in the-- 2. Upper Arroyo Grande basin 12 3. Santa Rita Creek basin 13 4. Graph showing mean monthly precipitation near San Luis Obispo, 1869-1972 13 5. Graphs showing flow duration curves for Arroyo Grande above Phoenix Creek, near Arroyo Grande, Lopez Creek near Arroyo Grande, Santa Rita Creek near Templeton, and Santa Rita Creek tributary near Templeton 14 6. Sketch showing effective sampling zones of various sediment samplers used in the upper Arroyo Grande and Santa Rita Creek basins 15 III IV CONTENTS Page Figure 7. Graphs showing the relation of bedload discharge to water discharge at Lopez Creek near Arroyo Grande, Santa Rita Creek tributary near Templeton, and Santa Rita Creek near Templeton 16 8. Graph showing the relation of total sediment discharge to water discharge at stations in the upper Arroyo Grande and Santa Rita Creek basins, 1968-73 17 TABLES Page Table 1. Water discharge for selected stations in the upper Arroyo Grande basin 21 2. Water discharge for selected stations in the Santa Rita Creek basin 21 3. Water discharge at Salinas River near Pozo 22 4. Available records of sediment discharge in the upper Arroyo Grande and Santa Rita Creek basins 23 5. Bed-material and streamf low data for selected stations in the upper Arroyo Grande and Santa Rita Creek basins 24 6. Bedload discharge in the upper Arroyo Grande and Santa Rita Creek basins, 1968-72 26 7. Runoff and total sediment yields in the upper Arroyo Grande basin, 1943-72 27 8. Runoff and total sediment yields in the Santa Rita Creek basin, 1943-72 28 9. Average annual sediment discharge of upper Arroyo Grande and Santa Rita Creek basins, 1943-72 29 CONVERSION FACTORS Factors for converting English units to metric units are given below to four significant figures. However, in the text the metric equivalents are shown only to the number of significant figures consistent with the values for the English units. English Multiply by Metric acre-ft (acre-feet) 1.233 x 10-3 hm3 (cubic hectometres) acre-ft/mil (acre-feet 4.762 x 102 m3/km2 (cubic metres per per square mile) square kilometre) ft (feet) 3.048 x 10-1 m (metres) ft/s (feet per second) 3.048 x 10-1 m/s (metres per second) ft3/s (cubic feet per 2.832 x 10-2 m3/s (cubic metres per second) second) in (inches) 2.54 x 101 mm (millimetres) lb/ft3 (pounds per 1.602 x 104 g/m3 (grams per cubic cubic foot) metre) mi (miles) 1.609 km (kilometres) mil (square miles) 2.590 km2 (square kilometres) tons (short) 9.072 x 10-1 t (tonnes) ton/d (tons per day) 9.072 x 10-1 t/d (tonnes per day) ton/mil (tons per 3.503 x 10-1 t/km2 (tonnes per square square mile) kilometre) V SEDIMENT DISCHARGE IN THE UPPER ARROYO GRANDE AND SANTA RITA CREEK BASINS, SAN LUIS OBISPO COUNTY, CALIFORNIA By J. M. Knott ABSTRACT Sediment data collected in the upper Arroyo Grande and Santa Rita Creek basins during the 1968-73 water years were analyzed to determine total sediment discharge at four stations in the basins. Water discharge and total sediment discharge at these stations, representative of the 1943-72 period, were estimated from long-term flow data for nearby gaging stations and water- sediment discharge relations determined for the 1968-73 water years. Most of the total annual sediment discharge at each station occurs during a few days each year. The quantity of sediment transported in a single day often accounts for more than 40 percent of the total annual sediment discharge. Estimated sediment discharge for the upper Arroyo Grande and Santa Rita Creek basins during the 1943-72 water years averaged 53,000 tons (48,000 tonnes) and 23,000 tons (21,000 tonnes) per year. Long-term sediment deposition in Lopez Reservoir, which is in the southern part of the upper Arroyo Grande basin, was estimated to be 35 acre-feet (0.043 cubic hectometres) per year. 1 2 SEDIMENT DISCHARGE, UPPER ARROYO GRANDE AND SANTA RITA CREEK BASINS, CALIF. INTRODUCTION This report was prepared in cooperation with the San Luis Obispo County Engineering Department. Sediment data were collected at stations in the upper Arroyo Grande and Santa Rita Creek basins and analyzed to determine the total sediment discharge at each station for the period of data collection and to make long-term estimates of the total sediment discharge. A 30-year period (1943-72) was used to define long-term sediment discharge. Sediment data used in the _study were obtained during the 1968-73 water years.' Most of these data were records of daily suspended-sediment discharge and daily total sediment discharge. Periodic measurements were made at some stations to determine bedload discharge and to obtain data for computing total sediment discharge. Previous Investigations Several investigations of sedimentation in San Luis Obispo County were made prior to and concurrent with this study. The U.S. Department of Agriculture (1953) surveyed the quantity of sediment deposited in several reservoirs in San Luis Obispo County. Fuller and others (1975) discussed various aspects of sediment transport in the Arroyo Grande basin. Much of the basic data available for the study area is in the U.S. Geological Survey Water-Supply Paper series, "Quality of Surface Waters of the United States-- Part 11," (U.S. Geological Survey, 1968-72) and the series, "Water Resources Data for California--Part 2, Water-Quality Records," (U.S. Geological Survey, 1961-72). Description of the Basins The upper Arroyo Grande basin (fig. 1), as referred to in this report, includes the entire drainage upstream from Lopez Dam and Reservoir, a major flood-control and water-supply facility in San Luis Obispo County. The area is mountainous with few inhabitants. Land use is generally limited to cattle ranching and recreation. 1 A water year is the 12-month period October 1 through September 30 and is designated by the calendar year in which it ends.
Load more

Recommended publications
  • LOMR)? for a One-Year Premium Refund
    the Arroyo Chico and Tucson Arroyo a FIRM. You may view this tutorial at: Property owners whose buildings have been watercourses. http://www.fema.gov/media- removed from an SFHA and are now located in library/assets/documents/7984 a Zone X or a Shaded Zone X may be eligible What is a Letter of Map Revision (LOMR)? for a one-year premium refund. Your lender When does a LOMR change a FIRM? must provide you with a letter agreeing to A LOMR is an official revision to the Flood remove the requirement for flood insurance. If Insurance Rate Maps (FIRMs) issued by the LOMRs become effective once the statutory your lender refuses to send you a letter stating Federal Emergency Management Agency Technical Appeal Period is over. The that they will not require flood insurance, you (FEMA). LOMRs reflect changes to the 100- effective date is listed on the LOMR cover will not be eligible for a refund. If you do not year floodplains or Special Flood Hazard letter. have a lender, you will not be eligible for a Areas (SFHA) shown on the FIRMs. In rare refund. To learn if you are eligible, please situations, LOMRs also modify the 500-year Can I drop my flood insurance if my follow these steps: floodplain boundaries. Changes may include residence or business is removed from ARROYO CHICO FLOODPLAIN modifications to Base Flood Elevations, the floodplain by a LOMR? 1. View the revised flood maps to REMAPPING floodplain widths, and floodways. The determine if your property has been re- QUESTIONS AND ANSWERS LOMRs are issued after a floodplain has The Flood Disaster Protection Act of 1973 mapped to a Zone X or Shaded Zone been remapped due to a major flood event, and the National Flood Insurance Reform Act X.
    [Show full text]
  • Drainage Net
    Drainage Net GEOLOGICAL SURVEY PROFESSIONAL f APER 282-A Ephemeral Streams Hydraulic Factors and Their Relation to the Drainage Net By LUNA B. LEOPOLD and JOHN P. MILLER PHYSIOGRAPHIC AND HYDRAULIC STUDIES OF RIVERS GEOLOGICAL SURVEY PROFESSIONAL PAPER 282-A UNITED STATES GOVERNMENT PRINTING OFFICE, WASHINGTON : 1956 UNITED STATES DEPARTMENT OF THE INTERIOR CECIL D. ANDRUS, Secretary GEOLOGICAL SURVEY H. William Menard, Director Fin* printing 19M Second printing 1K9 Third printing 1MB For sale by the Branch of Distribution, U.S. Geological Survey, 1200 South Eads Street, Arlington, VA 22202 CONTENTS Page Page Symbols. __________________________________________ iv Equations relating hydraulic and physiographic Abstract. __________________________________________ 1 factors....________-_______.__-____--__---_-_ 19 Introduction and acknowledgments ___________________ 1 Some relations of hydraulic and physiographic factors to Geographic setting and basic measurements ____________ 2 the longitudinal profile.___________________________ 24 Measurement of hydraulic variables in ephemeral streams, 4 Channel roughness and particle size.______________ 24 General features of flow _________________________ 4 Effect of change of particle size and velocity on Problems of measurement._______________________ 6 stream gradient.____.__._____-_______-____--__ 26 Changes of width, depth, velocity, and load at indi­ Equilibrium in ephemeral streams _____________________ 28 vidual channel cross sections ___________________ 7 Mutual adjustment of hydraulic factors._____.._._
    [Show full text]
  • Floods Floods Are the Most Common Natural Disasters in the Country
    Floods Floods are the most common natural disasters in the country. However, not all floods are alike. Some can develop slowly over a long period of rain or during warm weather after a heavy snowfall. Others, such as flash floods, can happen quickly, even without any visible signs of rain. It is important to be prepared for flooding no matter where you live, but especially if you live in a low-lying area, near water or downstream from a dam. Even a very small stream or a dry creek bed can overflow and cause flooding. Prepare supplies Make a Plan Stay informed Prepare an emergency supply kit, Develop a family emergency plan. Know the terms which includes items like non- Your family may not be together in the perishable food, water, battery same place when disaster strikes, so Flash Flood Warning: there has been a sudden flood. Head for operated or crank radio, extra it is important to know how you will flashlights and batteries. Consider contact one another, how to get back higher ground immediately keeping a laptop computer in your together and what you will do in case height. vehicle. The kit should include: of emergency. Flood Warning: there has been Prescriptions Plan places where your family will a flood or will there be a flood Bottled water, a battery radio meet, both within and outside your soon. It is advised to evacuate and extra batteries, a first aid immediate neighborhood. immediately. kit and a flashlight. Copies of important Be sure to take into account the Flood Watch: It is possible that specific needs of family members.
    [Show full text]
  • The Central Arroyo Stream Restoration Program
    This presentation premiered at WaterSmart Innovations watersmartinnovations.com Breaking Down the Barriers to Generate Sustainable Water Solutions The Arroyo Seco – A Case Study Tim Brick and Eliza Jane Whitman Arroyo Seco Foundation The Arroyo Seco Major tributary of the Los Angeles River Linking downtown LA to the San Gabriel Mountains Home of JPL and the Rose Bowl Watershed Management Program for last ten years Corps Feasibility Study The Historic Arroyo Seco Two different views of the Colorado Street Bridge The Most Celebrated Canyon in Southern California “This arroyo would make one of the greatest parks in the world” - Theodore Roosevelt, 1911 Current Status of the Arroyo Seco Though long celebrated as one of the most beautiful streams in Southern California, the Arroyo Seco has not escaped wide-spread damage caused by human impact Damage Caused by Urbanization / Channelization * destruction of habitat and wildlife * reduced infiltration * impaired water quality Central Arroyo Planning How does a golf course fit into watershed management and restoration? Alternative Alignments for Stream Restoration Celebrating the Arroyo The Central Arroyo Stream Restoration Program Improving the health of a stream and ensuring the future and sustainability of Pasadena The Central Arroyo Brookside Golf Course Project Accomplishments Improved water quality Enhanced trail network Implemented runoff BMPs Restored aquatic habitat Reintroduced the native Arroyo Chub Provided a model of stream restoration for urban SoCal Improved Aquatic Habitat ☼ Created backwater pools and structures to provide resting, foraging, and spawning areas for fish. ☼ Stabilized stream banks ☼ Improvements were constructed with natural materials (native trees and arroyo Backwater pool and stone). woody debris ☼ Under direction of CDFG, reintroduced 300 arroyo chub to the central Arroyo Seco.
    [Show full text]
  • Flowing Waters, Fruitful Valley a Brief History of Water Development in the Arroyo Seco
    Page 1 Flowing Waters, Fruitful Valley A Brief History of Water Development in the Arroyo Seco By Tim Brick Geographically and historically the Arroyo Seco has played an important role in the development of water resources in Southern California. The Natural History Geology divided the Arroyo Seco into three distinct sections with very different hydrologic characteristics: 1) the precipitous upper mountain watershed; 2) the Raymond Basin area including Pasadena and surrounding communities; and 3) the region below the Raymond Dyke in South Pasadena and northeast Los Angeles. • About half the length and area of the Arroyo Seco lies in the upper mountain watershed. This is the front range of the Sierra Madre or San Gabriel Mountains, well known for their harsh conditions. Fierce rainstorms and raging forest fires periodically attack the steep erosion-prone slopes in this relatively small upper watershed (32 square miles) to create the conditions for substantial floods that occasionally roar into the heavily populated communities below. As the Arroyo Seco emerges from the San Gabriel Mountains, its steep descent slows and the waters cut through an alluvial plain. Beneath this region, which includes La Cafiada-Flintridge, Altadena, Pasadena, Sierra Madre and part of Arcadia, lies the Raymond Basin - a massive bowl of alluvial sand and gravel filled with water. The south rim of the basin is the Raymond Dyke, a geological fault that runs from Highland Park to Raymond Hill at Pasadena’s southern boundaiy with South Pasadena and then through San Marino just north of Huntington Drive to Santa Anita Canyon on the east side of Arcadia.
    [Show full text]
  • 4.8 Hydrology and Water Quality
    Redwood City New General Plan 4.8 Hydrology and Water Quality 4.8 HYDROLOGY AND WATER QUALITY This section discusses surface waters, groundwater resources, storm water collection and transmission, and flooding characteristics in the plan area. Key sources of information for this section include the San Francisco Bay Basin Water Quality Control Plan (Basin Plan) prepared by the San Francisco Bay Regional Water Quality Control Board (January 2007), the Urban Water Management Plan (UWMP) for the City of Redwood City (2005), and the Unified Stream Assessment in Seven Watersheds in San Mateo County, California by the San Mateo Countywide Water Pollution Prevention Program (August 2008), Kennedy/Jenks/Chilton Consulting Engineers Water, Sewer Storm Drainage Master Plan dated 1986, and Winzler & Kelly’s Bayfront Canal Improvement Project Design Development Alternative Analysis, dated December 2003. 4.8.1 ENVIRONMENTAL SETTING Hydrologic Conditions The regional climate of the plan area is typical of the San Francisco Bay Area and is characterized by dry, mild summers and moist, cool winters. Average annual precipitation in the plan area is about 20 inches. About 80 percent of local precipitation falls in the months of November through March. Over the last century for which precipitation records are available, annual precipitation has ranged from an historic low of 8.01 inches in 1976 to an historic high of 42.82 inches in 1983.1 Surface Waters Figure 4.4-1 (in Section 4.4, Biological Resources) depicts surface water bodies in the plan area, which include Redwood and Cordilleras Creeks and their tributaries. Also shown are bay channels, including Westpoint Slough, Corkscrew Slough, northerly reaches of Redwood Creek, Smith Slough and Steinberger Slough, the Atherton Channel (Marsh Creek), and the Bay Front Canal.
    [Show full text]
  • Arroyo Seco Watershed Restoration Feasibility Study
    B. WATERSHED Description The Arroyo Seco Watershed is located in northeast Los Angeles, between the San Gabriel Mountains and the Los Angeles River (Figure 1: Location Map). Lying partially within the watershed are the cities of Los Angeles, South Pasadena, Pasadena and La Cañada Flintridge, as well as the unincorporated area of Altadena (Figure 2: Arroyo Seco Watershed, Figure 3: Topographic Relief). Two of Los Angeles County’s five Supervisorial Districts can be found in the watershed, as well as three U.S. Congressional Districts (Figure 4a: Elected Official Boundaries 1). For the State of California, the Arroyo Seco watershed intersects three Senate Districts and four Assembly Districts (Figure 4b: Elected Official Boundaries 2). The southern tip of the watershed was a camp location of the first Spanish exploration, and the historic irrigation zanjas were located just across from the confluence. As one of the oldest parts of Los Angeles, the Arroyo Seco contains many cultural and historic attractions, as well as several Historic Preservation Overlay Zones. This area of Los Angeles is known world-wide for its concentration of Arts and Crafts heritage and many original Craftsman structures. The Historic Route 66 runs through the watershed; historically, travelers to Los Angeles entered through the Arroyo’s gateway of Sycamores. The Arroyo Seco Watershed is a sub-watershed of the Los Angeles River Watershed, which is a coastal watershed partly within the coastal zone. The Arroyo Seco stream runs in a deeply incised canyon that begins in the San Gabriel Mountains and drains into the Los Angeles River near downtown Los Angeles.
    [Show full text]
  • What's Inside
    what’s inside Clean Beaches and Water Quality State of Our Watersheds Arroyo Burro Mission Creek Sycamore Creek Laguna Creek Community Priorities How You Can Help Benefits of a Healthy Watershed a community guide to watershed action plans b clean beaches depend on healthy watersheds The abundance of mountains, hills, natural areas, creeks and beaches contributes to Santa Barbara’s reputation as one of the most beautiful areas in the world. As stewards of this environment, we all play an important role in preserving and enhancing our watersheds. We all live in a watershed—land that is our watersheds is revealing new opportunities to drained by a creek system that flows to the address these challenges. ocean. The health of our creeks and beaches Community Input is linked to the health of our watersheds. As a first step, in late 2004, the Creeks Division The purpose of this guide is to inform Santa held a series of community forums. Hundreds of Barbara residents about the state of our people offered their thoughts about the creeks watersheds and to provide a foundation for and potential watershed goals and priorities. Key developing action plans to improve our issues included trash, water quality, water manage- creeks and ocean water quality. ment, habitat protection, recreation, public education, and how the community can help. Our City Community priorities identified during the work- The Creeks Division Santa Barbara is a relatively dense urban area, built shops are summarized on page 14. More detailed mostly within the boundaries of four major water- The mission of the City of Santa reports are posted on the Creeks Division web sheds.
    [Show full text]
  • Senate Bill Text for SB0486
    1 SENATE BILL 486 2 49TH LEGISLATURE - STATE OF NEW MEXICO - FIRST SESSION, 2009 3 INTRODUCED BY 4 Gerald P. Ortiz y Pino 5 6 7 8 9 10 AN ACT 11 RELATING TO SPECIAL DISTRICTS; LIMITING THE POWERS OF CERTAIN 12 CONSERVANCY DISTRICTS OVER ACEQUIAS AND COMMUNITY DITCHES. 13 14 BE IT ENACTED BY THE LEGISLATURE OF THE STATE OF NEW MEXICO: 15 Section 1. Section 73-14-39 NMSA 1978 (being Laws 1927, 16 Chapter 45, Section 308) is amended to read: 17 "73-14-39. GENERAL POWERS.-- 18 [(1)] A. Except as provided in Subsection D of this ] = delete 19 section, in order to protect life and property within the 20 district, and to protect or relieve land subject to overflow or 21 washing or which is menaced or threatened by the normal flow of 22 flood or surplus or overflow waters of any natural water 23 course, stream, canyon, arroyo or wash, whether perennial, bracketed material 24 intermittent or flood, and in order to effect the protection of underscored material = new [ 25 life, land and other property in the district, and to .175681.1 1 accomplish all other purposes of the district, the board is 2 authorized and empowered: 3 (1) to clean out, straighten, widen, alter, 4 deepen or change the course or terminus of any ditch, community 5 ditch or acequia, drain, sewer, flume, river, water course, 6 pond, lake, creek, arroyo or natural or artificial stream in or 7 out of [said] the district; to fill up any abandoned or altered 8 ditch, community ditch or acequia, drain, sewer, river, flume, 9 water course, pond, lake, creek, arroyo or natural or 10
    [Show full text]
  • Arroyo Viejo Creek Restoration Complete!
    Creeks - Arroyo Viejo Creek Restoration Complete! Arroyo Viejo Creek Restoration Project COMPLETED, January 2002 THE ARROYO VIEJO Creek Restoration Project in Arroyo Viejo Park is completed. After two years of preparations and plans, project implementation began last July and was completed at the end of January 2002. Sponsored by the City of Oakland, the California Coastal Conservancy , and the Alameda County Flood Control and Water Conservation District, the project removed failing cement structures, stabilized banks, and restored native vegetation along a 750 linear-foot stretch of creek. These changes will help to restore ecological balance and riparian habitat, improve water quality, while enhancing public access and safety, and recreational and educational opportunities for an underserved population of East Oakland. 760 tons of concrete was removed from the creek banks and bed and crushed for reuse by Aman Environmental, a debris-recycling company. The decaying concrete walls were replaced using a variety of bio-engineering techniques. For example, trunks from non-native trees removed from the site were used to secure the creek banks in several areas. Brush layering and willow staking were also used. A dilapidated, unsafe, concrete amphitheatre was replaced with terraced pervious seating and a stage area, made from decomposed granite, sculpted into the grade of the creek bank. Replacement of the old amphitheatre allowed room to broaden the creek channel which in turn helped to increase flood capacity, visibility and enhance safety, while providing a new performance space for community theatre, music and dance performances. The 4,500 cubic yards of soil removed from the banks to broaden the channel were donated to the Hayward Area Regional Park District to be used in a wetlands restoration project.
    [Show full text]
  • Evolution of an Anthropogenic Desert Gully System
    Erosion, Transport and Deposition Processes (Proceedings of the Jerusalem Workshop, March-April 1987). IAHS Publ. no. 189,1990. Evolution of an anthropogenic desert gully system MARTIN J. HAIGH Geography Unit, Oxford Polytechnic, Oxford 0X3 OBP, UK Abstract Studies of an unusual quasi-stationary desert gully permit the description of a system attractor which may be inherent, if rarely physically expressed, in many gully systems. Measurements made in a desert gully system (controlled by the seepage of irrigation waters towards a stable base level) suggest a character for the attractor’s equilibrium manifold. This is modelled mathematically as an hysteresis or limit cycle in phase space. Overall, the phenomenon is seen to belong to a kind of hierarchical process associated with the Scheidegger "principle of instability/saturation effect". It reflects a dynamic balance between two hierarchical levels inside a single system. The system includes a singularity which is an example of an hierarchical jump caused by the reintegration of a self-assertive holon. INTRODUCTION Greene’s Canal, on the borders of Pima and Pinal Counties in southern Arizona, is an arroyo. It was created between 1908 and 1910 as a diversion ditch (6.1 m wide by 1.5 m deep) for an agricultural development project. This involved the redirection of flood waters from the Santa Cruz River to a shallow earth-dammed impoundment on the Lower Santa Cruz Plains (Fig. 1). Unfortunately, the dam was destroyed and the project wrecked by severe floods in the years 1914-1915. These floods, called "the worst for generations" (Peirce & Kresnan, 1984), cut the canal into a 3.7 m deep trench, which is twice the depth of the Santa Cruz river at the original point of diversion (Timer et al., 1943; Cooke & Reeves, 1976).
    [Show full text]
  • The Canals of Harlingen Norman Rozeff Harlingen Is Crisscrossed
    The Canals of Harlingen Norman Rozeff Harlingen is crisscrossed with numerous irrigation water delivery canals. They have been in existence so long that they have melded into the scenery and are unobtrusive to most. The fact is that their existence, in great part, helped to establish the city. Lon C. Hill's sales of commercial and residential lots in the new town were predicated on the production of agriculture commodities in the surrounding land. Sugarcane, corn and vegetables came first then cotton and citrus rose to supremacy. None could have made it in this semi-arid climate without irrigation water. What made it all possible was gravity flow to the north, for the river sits at an elevation of 61' above sea level while the area to Harlingen's north is only 32'. Here is how this very important ingredient was introduced from the river to the areas north of Harlingen by Hill's Harlingen Land and Water Company: January 1907 Canal intake excavation work at the river about 9.75 miles south of the Arroyo Colorado is in progress. Later in the year 450 men and seventy teams of mules and horses will be hard at work on the canal under the supervision of experienced engineer John D. Hill. This Hill, no relation to Lon, had previously been employed in Brownsville at Lon C. Hill's hardware and implement store there. 8/17/07 Plans are made for starting the power house pumping plant to lift water from the river into the Harlingen Canal. A.R. Mann, a mechanical engineer from Chicago, is engaged to take charge of the machinery.
    [Show full text]