Livestock grazing as a vegetation management practice in fremont weir wildlife area

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Organizational Practices of Infrastructure

Livestock grazing as a vegetation management practice in Fremont Weir Wildlife Area Boya Ye

Figure 1: Arial View of FWWA

ABSTRACT Fremont Weir Wildlife Area (FWWA) embeds Fremont Weir, an overflow structure that passes floodwater and controls storm flows that would otherwise flood farmland and City of Sacramento. Thanks to the periodic flooding events, FWWA is a natural habitat for many birds and fishes species and as well as a piece of public open space for recreation and research. Vegetation management makes sure that FWWA maintains its optimal capacity for flood water conveyance to Yolo Bypass. While vegetation in FWWA creates food and shelter for the wildlife species, heavy clusters of vegetation will block the water flow once it is flooded, putting city of Sacramento into great risks of economic losses and flooding damages. This case study evaluates the vegetation management in FWWA, particularly the use of livestock grazing. By studying how grazing works in FWWA, critically examining its benefits and limitations in FWWA, and comparing grazing to other mechanical or chemical treatments, this case study suggests the challenges of applying a particular

organizational practice to an infrastructural landscape and discusses the potential of grazing to be applied in other infrastructural landscape maintenance. This case study is organized into five sections. Section I establishes the theoretical framework for this essay and defines biophysical landscape as infrastructure. Section II describes the research methods employed in this case study. Section III starts with the historical emergence of FWWA, and introduces how vegetation management starts to play a role and persists in FWWA. Section VI focuses on the specific role of livestock grazing as one of the vegetation management tool. Section V concludes with the value and state of grazing in FWWA; proposes some speculative suggestions;and discusses the implication of this case study to the levee maintenance in Sacramento-San Joaquin Delta.

KEYWORDS: Fremont Weir, Livestock grazing, Landscape, infrastructure


Figure 2: Flood Flow of FWWA

Section I: Defining Infrastructure Traditionally-defined infrastructure treats natural resources as capital assets and strives to impose a rigid and systematic control over the inherently variable natural environment. However many times infrastructure fails and leads to great damages when natural disasters such as earthquakes, climate change and other extreme weather conditions are beyond the orderly control of human beings. Today, infrastructure is redefined and envisioned as ecosystems-building that can respond to changing environmental conditions. With this new definition,biophysical landscape are reformulated as infrastructure that generates and supports economy, rather than fuel simply exploited for industrial economic development. (Edwards,2003;Reed and Lister,2014;Belanger,2009) Star and Ruhleder argues that infrastructure is a concept fundamentally about relationship with specific practices. Essentially infrastructure is about the function, benefits or services it delivers and the process of assemblage. As much as we care about those visible

services, organizational practicesthrough which hardware components and political-economic elements are networked for service deliverydetermine the emergence, performance, and failure of infrastructures. Those organizational practices represent the actors and agencies in the assemblage of infrastructure. This case study focuses on the organizational practices that accrete around infrastructure, and examines the embeddeness, the influence, the priorized environmental services and the modular increment of such practices.(Star,1999; Carse,2012;Bennett,2010) Fremont Weir Wildlife Area (FWWA) as infrastructure Located about 15 miles northwest of Sacramento and 8 miles northeast of Woodland, Fremont Weir Wildlife Area(FWWA) situates the Fremont Weir, a flood relief structure completed in 1924. At the confluence of Sacramento River, Feature River and Sutter Bypass, Fremont Weir acts as the first line of defense against flood damages in the greater Sacramento region. During high flood stages, it allows overflow waters


of the rivers to connect to the 59,000acre Yolo Bypass, a diverse wetland habitat designed to convey 80 percent of Sacramento River floodwaters; during low flood stages, it interrupts the flood plain and separates water in the Sacramento River. Acting as the site for water level management and flow measurement, FWWA also enhances environment by creating a rich and diverse habitat for both aquatic and terrestrial species and reclaims the agricultural lands for local economic development.(DWR,2010)

reaching the upper end of FWWA. Scour channels are formed across FWWA ranging from 31 feet to 20 feet, resulting in diverse land type such as riverine, fr esh em er gent wetland, per en ni al grassland, annual grassland, valley foothill riparian and valley oak woodland (Fish and Games,2012;DWR,2010). These channels in FWWA pose special topographic challenges and opportunities for the vegetation management practices.

Actors and their agency of FWWA

Figure 4:

Figure 3: Technical and Social components

Both hardware components and social organizations are involved as actors in FWWA. The hardware components of FWWA consist two parts: Fremont Weir Structure and Fremont Weir channel. Fremont Weir Structure includes a fixed-level, concrete overflow section; a concrete, energy dissipating stilling basin;a rock erosion blanket across the channel beyond the stilling basin;and a pair of training levees that define the weirflow escape channel (Figure 4). The crest elevation is 33.50 feet and the design capacity of the weir is 343,000 cfs. Natural levees are on the unprotected south bank and out of bank flows disperse through a series of tree covered areas of higher ground dissected by distributary channels until

Three social organizations shown in figure 5 are involved in FWWA : Reclamation Board of the Sacramento and San Joaquin Drainage District, CA Department of Fish and Games (Fish and Games) and CA Department of Water Resources(DWR). The reclamation Board of the Sacramento and San Joaquin Drainage District has control and possession of the construction, operation and maintenance of flood control works. To encourage the development and maintenance of fish and wildlife habitat areas, the Reclamation Board leases certain real property interests to the Department of Fish and Game for a period of fifty years from April 1, 1977 to March 31, 2027. Today Fish and Games m a n a g e s F W WA f o r p u b l i c a c c e s s into FWWA for hunting and recreation. The California Department of Water Resources (DWR) on behalf of the State of California, as required by the California


Figure 5: Human Agencies in FWWA

Water Code, operates and maintains facilities of the State-federal flood protection system within the Sacramento Valley of California, per assurances provided to the federal government by the State through Central Valley Flood Protection Board (formerly the Reclamation Board). DWR implements ongoing operations and maintenance activities on levees, within channels, and on appurtenant structures in FWWA. Through vegetation management, DWR maintains channel design flow capacity, levee integrity and proper functioning of flood management structures (Fish and Games,2012;DWR,2010) Vegetation Management as organizational practice Even though the weir structure in FWWA requires limited amount of operation and maintenance to pass overflow water, vegetation management is critical in maintaining the floodplain roughness in Fremont Weir channel. is critical in the determination of how much flow capacity FWWA can carry. The configuration patterns of vegetation is the main factor in the determination of how much flow capacity FWWA can carry. Vegetation management practices supports FWWA to perform at it optimal level and is the

focus of this case study. Vegetation management practices in FWWA faces specific topographic challenges and different social organizations are involved. While traditional chemical and mechanical treatments are taking place, livestock grazing is an exciting approach that fits in FWWA and brings out collaboration of different social organizations. (Rickard,2003;DWR,2015)

Section II: Approach This case study explores the notion that biophysical landscape performs as infrastructure are in fact sociotechnical in nature. The vegetation management plays a critical role in supporting the service delivery of Fremont Weir as well as the Sacramento River Flood Control Project. The Fremont Weir Wildlife Area is an especially illuminating site to think about landscape as infrastructure because nonhuman and human actors with different goals and objectives are inextricably inter-wined there. R ese ar ch m e th od s e m pl o y ed in this case study include: visual modes of analytical diagrams and photography;narrative writing drawn from historical analysis and other archival materials;and site visits and interviews. I first studied the functions and components


Figure 5: Timeline of FWWA History

of Fremont Weir through historical documents and technical reports. Historical analysis was conducted to learn the emergence of Fremont Weir and FWWA. I used archival materials such as project files, newspaper articles, public records and internal policies to study how FWWA emerged, organized and maintained by vegetation management. To u n d e r s t a n d t h e i n t e r a c t i o n s between different actors in FWWA, I interviewed CA Department of Water Resources Sacramento Maintenance yard, Department of Fish and Games specialist and local stakeholders. For the critical examination of livestock grazing in FWWA, reflections from site visits, documents studies and interviews contribute to the discussion of the benefits and constraints of grazing.

Section III: Historical Emergence of FWWA and its persistence Fremont Weir emerged as part of the

Sacramento River Flood Control Project, resulted from the long flooding history and floods management in Sacramento Valley (Figure 5). Prior to flood management, the whole Sacramento valley floor would be covered by a blanket of seasonal runoff nearly every year. Rapid surface water runoff that entered and over-topped the Sacramento River came from the occasionally large amounts of rain in the Coastal ranges and the relatively steep geographic ranges if Sierra Nevada mountain (DWR,2010). 1850-early 1900s| Absence of overall coordination of flood control planning The historic settlements of Sacramento and West Sacramento were established and populated in the 19th century. At that time, local communities formed drainage and reclamation districts to protect their own lands; neither the state nor the federal government was turned to for the service of flood protection.In 1850s, the first levee in Sacramento was built due to


Table 1: Timing and Frequency of Maintenance activites in FWWA

the two floods in 1850;however the levee failed soon in the following year. Early 20th century-1970s| Federal government took the role The 1907 and 1909 floods costed great damages in Sacramento Valley, leading to the establishment of State Flood Control Act in 1911. At the same time, Army Corps of Engineers came to the Sacramento Valley to help with navigation because river navigation was hampered by sediments from hydraulic mining. In 1937, the Fremont Weir was built in 1937 as part of the Central Valley Project. It setted back an average of 200’ from the river, and paralleled the river for the length of about 1.5 miles. In 1957, Army Corps of Engineers handed it to the responsibility of the State of California. 1970s-1980s| Development of the system In 1970s, there was a national debate over how to address flood damage. 1978, Sacramento valley communities

joined National Flood Insurance Program, which permits the continuation of system development and management. While funding for Fremont Weir operation was secured, the property was designed as a wildlife area by the Fish and Game commission in 1981. 1980s-Current| Testing the system 1986 Flood and 1997 Flood poured nearly 600,000cfs into Sacramento-San Joaquin Delta through Fremont Weir and Yolo Bypass. This prevented the City of Sacramento from suffering from large costs and damages. The design capacity of FWWA and Yolo Bypass has not yet been exceeded during numerous floods in the past decades thanks to the operation and maintenance in FWWA The emergence and persistence of Vegetation management in FWWA The California Department of Water Resources(DWR) started to maintain both Fremont Weir structure and the flood channels in FWWA since 1957. The


CA DWR Sacramento Yard maintains the Fremont Weir structure to avoid clogging by aquatic vegetation and the Fremont Weir Channel to keep conveyance capacity from sedimentation, encroachment of vegetation, beavers building lodges and dams, encroachments and unauthorized dumping of debris. Table 1 shows the different tasks and their frequencies performed in the weir maintenance and the channel vegetation management.(DWR,2015)

Section IV: The role of grazing in FWWA In 2007, Gary Hobgood, Environmental Scientist with Fish and Games suggested to explore sheep grazing in FWWA. At that time, the vegetation management was limited to mowing or herbicides. Thus, Fish and games initiated a grazing program with coordination to the Department of Water Resources Management Division’s Sacramento Maintenance Yard. Since then, sheep grazing has been practiced in FWWA to reduce the overall height of herbaceous and woody vegetation from April to October every year. The intent was to reduce floodway roughness, maintain floodway capacity, reduce potential derbis accumulation and promote native plants establishment and growth.(Department of Fish and Games, 2007)

Figure 6: Pasture Land division in FWWA

How grazing works in FWWA Livestock grazing in FWWA works under the Permit for Excess Vegetation Disposal issued by Fish and Games. They year before the old permit expires, Fish and Games releases an invitation for bidding the permit and chooses the highest permit price per sheep unit month from the bidders. The permit lasts for period about four years and eleven months. After choosing the bidder, Fish and Games will update DWR maintenance crew to adjust their regular maintenance schedule accordingly. DWR maintenance crew sometimes request “limbing up” large stands of riparian trees through grazing. Monitoring and inspection from the FWWA manager occurs once a month during the grazing periods. The chosen bidder starts grazing in the following July and ends in October before the start of hunting seasons. Upon the request of DWR maintenance crew, grazing starts from the east side of FWWA and goes in order into three pasture land divisions (Figure 6). Pasture Land 1 on the northern portions of FWWA is grazed first and its top priority is to reduce vegetation roughness near the Sacramento River. After pasture Land 1 is cleared out, FWWA manager will allow the entry in Pasture Land 2 on the west side, and then Pasture Land 3, which is the flood channels.Pasture Land 1 and 2 are grazed to little residual dry matter remaining to receive flood water quickly, while pasture Land 3 is grazed to about 1500 Lbs/acre residual dry matter to avoid overgrazing (Table 2). Grazing is not allowed around the Misner’s mound, oak islands and riparian areas in FWWA for habitat protection purposes.(Department of Fish and Games, 2012)


The advantages of grazing in FWWA Grazing in FWWA has not only functional significance but also environmental and economic benefits at a regional scale. Grazing maintains floodway capacity of FWWA by clearing out grasses and low lying limbs that would otherwise install flood water and collect debris during flood events. So far grazing’s flexibility to move around the channel section plays an irreplaceable role in FWWA. of grazing. Meanwhile, vegetation clearance encourages the growth of forbs, shrubs, and trees and controls invasive species. The removal of decadent grasses contributes to the sustainable levels of above ground biomass, root growth, and root strength. With proper grazing management, grazing defoliates dormant growth between the overbank flow events and enhances erosion control by increasing the root strength of riparian vegetation. In that way, the enhanced establishment of native plant species creates habitats for endemic birds and fishes, preserving biodiversity. In addition, research as well as real-life experiences have demonstrated that sheep and goats are promising tools in the battle of invasive weeds control. Actually, ungrazed lands are proven to be more vulnerable to invasive grass species and fire damages than grazed lands. ( Perry,2010; Fish and Games,2014;DWR,2012) What’s more, grazing is economically valuable in both FWWA and Sacramento Valley. Grazing is less invasive and detrimental compared to the other management alternatives such

as mowing and herbicides. According the Sacramento Maintenance yard, the cost of use tractors and mechanical equipment largely reduced in the years of grazing. Those mechanical machines use fossil fuel intensively and contribute to the greenhouse gas emission and local pollution. Likewise, the application of herbicides usually costs more money and has a high possibility of contaminating the river via chemical residue. In addition, grazing fits in the agricultural background of Sacramento Valley. Sacramento Valley, especially Yolo County has reported a diminishing trend of pasture land availability in the past decades. FWWA grazing provides an opportunity for regional livestock producers to continue t h e i r c a r e e r. ( L a u n c h b a u g h , 2 0 0 6 ; Sommer,2001) The problems and limitations of grazing in FWWA 1.Physical constraints The bidders for grazing permits are mainly concerned about the Water availability and the accessibility in FWWA. Water source, which is essential for sheep, is not guaranteed in FWWA, especially in drought years. Despite FWWA’s proximity to the Sacramento River, river water is not accessible for sheep due to the steep slopes of river banks. Also, the ongoing California drought has kept the ground water table too low to acquire water from the scour ponds and oxbow in FWWA. The only reliable water source for grazing is from Tule Canal, a privately-owned agricultural canal on the south. However, buying water from this outside source leads to inconvenience and increased costs for grazing. (Fish and games, 2012;DWR,2015) Another big concern is the accessibility to and in FWWA. Sheep


Figure 7: Benefits and Constraints of Grazing in FWWA

used to enter the property from County 16 on the east side and exit from the parking lot on the west side. In 2014, the parking lot on the west side was found to be on the private property of Mary Edson. Since then, the access from west side remained closed. This closure means that the vehicles that carry sheep can only enter and exit via County Road 16 and park along the levee. Thus, traveling from FWWA to the next grazing site in October becomes cumbersome. (Fish and games, 2015;DWR,2015;Case,2014) 2.Timing constraints Grazing practices in FWWA needs to adjust according to the varying flood patterns and accommodate to hunting and public access. Even though the grazing contract is from July 15 to August 30, the actual grazing time in FWWA varies from year to year, depending on the varying flood events frequencies. On average, FWWA floods every 5 years and lasts for several months each time. The water is contained about 2 feet over the weir structure, and grazing has to end prior to the flood.

Even in the years without flooding, grazing has to end before the beginning of hunting seasons to avoid conflicted use. According to years of observation from DWR maintenance crew, grazing time in FWWA is generally in short due to its time structure. Many times Pasture Land 1 and 2 has been grazed effectively while grazing time in Pasture Land 3 is insufficient. Nevetheless, Pasture Land 3 is where tractors and mowers cannot easily operate due to its cragged topography and holes of various depth. In this way, Pasture Land 3 is covered by denser vegetation cover that has a higher possibility to accumulate debris and block water. (DWR, 2015; Fish and Games,2015) 3.Regulational and economic constraints Regulations require administration,which can be time- and resources-consuming from the permit initiation to the program monitoring.Fish and Games staff will monitor grazing activities every month to ensure compliance with the leasing contract and avoid negative environmental impacts to wildlife habitat. Sometimes


the grazers will need to extend or reduce grazing period if there is a vegetation monitoring plan or range management studies happening in FWWA. Furthermore, some specific regulations states that none of built structures except electric fencing is allowed in FWWA. Hence, livestock producers cannot built tents in FWWA to take care the sheep during nights. This lack of residential accommodation discourages many potential bidders in Yolo County. (FIsh and Games, 2012) What’s more, many bidders stated that it was not economically feasible to bid the permit. Not only do bidders pay for the permit fee, they are also subject to costs in preparing for bidding documents and any operation costs in grazing. With lack of subsidies,economic recession, and severe drought, many livestock producers in Yolo County reduced their herd sizes and grazing season. (Mashiri,2015; FIsh and Games,2015)

Compared to Mower Mechanical mowing by DWR happens every year after grazing. Tractors cannot operate on cut banks and steep channels. Therefore mowing is only limited to the range of pasture land 1 and 2. Mechanical treatments can be costly and run on fossil fuel, which releases greenhouse gas and worsen global warming.(DWR,2015)

Figure 8: Compare Grazing to other alternatives

Compare grazing to other alternatives

Section V: Conclusion and Discussion

Compared to Herbicide Herbicide is applied by DWR every year on the Fremont Weir Structure. It can be costly to use aquatic safe products that would not contaminate the river. Since the floodplain in FWWA has plenty of invasive species, application of herbicide will be make FWWA more vulnerable to weeds and detrimental to the endemic plant diversity. The vast roadless extent of channel floodplain makes it difficult to control noxious weed with herbicides or to reestablish desirable forage plants after spraying. (DWR,2015)

Conclusion

Compared to fire Fire is applied by DWR along the levee road on east and west sides. It requires very high coordination and is not appropriate in FWWA, which allow public access. Concern over air pollution and risk of unintended spread hesitates prescribed burning in FWWA.(DWR,2015)

I n t h i s c a s e s t u d y, I h a v e e x a m i n e d t h e development of a regional infrastructure that meets the flood control and habitat creation needs in Sacramento region. In FWWA, there are not only Weir Structure, Channel habitat as artifact infrastructure, but also vegetation management as a relationship-building infrastructure. The technical, governmental, and administrative organizational practices connect all the artifacts to perform their functions. Since different actors represent different agencies inhabit FWWA with same resources yet slightly different roles, there exist conflicts of agencies that will in return shape the infrastructural landscape. DWR’s first consideration of flood control is an impetus to clear out vegetation cover in FWWA more is at odds with Fish and Games’ main reliance on the plant species to create habitats. The questions of which ecosystem


service of FWWA to prioritize becomes an influential factor determining the vegetation management target in FWWA. Livestock grazing can be a middle ground where the goals and objectives of these two organizations align together and perform in efficiency. Yet livestock grazing is only part of the solution. Due to the binding constraints for grazing analyzed above, livestock grazing cannot completely substitute other alternatives currently and works best as accompany of mowing. Overall the role of grazing in FWWA is Irreplacable because of its many advantages over mowing, herbicides and burning. The spatial, temporal, technical and political challenges of grazing reflects the particular sociotechnical characteristics of FWWA. As the actors and agency shape the landscape of FWWA, the solution to conquer those challenges reside in the interaction between those actors. Discussion Cost and Revenue Analysis The cost associated with the grazing program consists of two parts: a high fixed cost of administration work and a low variable cost which is covered by the permit fee. According to Joshua Bush, there is no minimum price that Fish and Games would not accept for grazing as long as the bidder is reliable. Permit fee charged by Fish and Games is calculated as “the product of the winning bid amount per SUM per grazing period times 2000 Sheep Unit Months (SUM)�. While the annual permit fee covers the variable cost of consuming vegetation by the sheep, California tax payers pay for the administration costs through General Funds(DWR,2015) The pricing structure of grazing program in FWWA is supposed to be economically efficient because it equates marginal benefit with marginal cost associated with grazing. However standing from the perspective of bidders, bidders will lose money because those physical, timing and regulation constraints increase the input costs and create a binding production constraint for grazing. Supply and Demand Analysis Given the need for grazing is necessary in FWWA, the demand for grazing is inelastic-constantly in need and fixed in amount. On the other hand, the increased costs to bid and the binding production constraint due to timing issues all account for decreased supply of grazing services that would participate in the biding. The following speculative

suggestions are based on the goal to increase supply of grazing services in FWWA and maximize the benefits of grazing in FWWA, and these suggestions will need more research to test out the impacts. 1.Increase the Service supply through cost minimization: A.local collations or organizations of grazing

This local organization can help bidders to prepare all the paper work for the bidding of permits. Not only do bidders save money from processing documents separately, the concentration of resources will also provide local farmers with better information in the market. A collation has a concentration of voice that works more effectively in requesting subsidies and influencing the local policy. B. Work with nearby farmers to solve water source and accessibility issues

Given the many private properties surrounding FWWA, it would be a good idea to have the grazing program collaborate with nearby farmers. Either nearby farmers can bid for the permit or they will provide housing and other amenities to grazers at some costs. In this way, the problems of residential accommodation and water sources are solved on the site. This strategy may possible enhance the relationship between public and private land ownership in FWWA. Private property owners are an effective actor in FWWA, and they should be well educated about the function of infrastructure. As the land protected by Fremont Weir is in the interests of local residents, they will have a sense of ownership and responsibility to help maintain the work of FWWA. 2.Increase the service supply through other methods A.Support the local agriculture economy

Grazing Land constitutes 23 percent of land in Yolo County, and beef cattle and lamb, and milk have been increasing in production and value. If the demand for local cattle, lamb and milk increases, the prices of those products will grow. According to the "Law of Supply", there is a positive relationship between price and the amount of grazing services supplied. B. Increase the awareness of need in vegetation removal

Due to the failure of this closest bidding event in 2014, vegetation in the channel will become denser and the value of grazing starts to grow. Thanks


to grazing’s advantages over other alternative vegetation management methods, more programs are expected to support the grazing program and increase the supply. 3.Maximize the benefits of grazing A.Employ targeted grazing in FWWA

Working with the limited time available for grazing due to the flooding and hunting schedules, it is critical for DWR and Fish and Games to establish mutual understanding and identify a target for livestock grazing. The grazing regime listed in the contract shall adjust according to the target. For example, is avoiding flood water blockage is the main target, then grazing should target at creating a shorter canopy height in the wildlife area. In that way, increasing the stocking densities of sheep is preferable in grazing regime, and the grazing order can be changed.(Nolte,2014). On the other hand, if different parts of the canopy layers are the target of clearance, then use of different species is recommended. B. More flexible grazing regime

In the years without floods and vegetation clearance is in urgent need, the grazing period can be extending. With proper management, it is likely that grazing and public access can work at the same time.



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