San Francisquito Creek Watershed Sustainability Analysis: A Novel Approach
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Veronica Chouinard
A Thesis in the Field of Sustainability and Environmental Management
for the Degree of Master of Liberal Arts in Extension Studies
Harvard University
May 2018 Copyright 2018 Veronica Chouinard Abstract
In the western US, most water consumers rely on imports from outside their local watershed. This has implications for both the recipient watershed as well as those which provide the water. The most widely-used metric available to quantify watershed sustainability, the Watershed Sustainability Index (WSI), assumes that water used within the watershed originates there. This research aims to identify and address shortcomings of this metric. Specifically, I adapt the WSI to accommodate watersheds in which imports and exports warrant consideration, I integrate additional sustainability indicators, and I present the results in a treemap. I applied the resulting tool, the Watershed
Sustainability Visualization (WSV), to the local San Francisquito Creek (SFC) watershed to evaluate watershed management effectiveness. I hypothesized that the SFC watershed would perform poorly in a sustainability analysis on hydrological and environmental dimensions, despite the perception that it is healthy and well-managed. Using data available from local agencies and existing databases, I calculated the SFC WSV scores for each indicator. I evaluated the indicators for hydrology and environment and determined that although the quantitative sub-indicator for hydrology supported my hypothesis, the others did not. Furthermore, I hypothesized that, although robust, current management efforts may not adequately address dimensions on which the watershed sustainability analysis indicates a need for improvement. As it turns out, issues are being addressed; however, it remains to be seen whether the outcome will have a favorable or unfavorable impact on sustainability. Acknowledgments
To my research advisor Mark Leighton – I appreciate your guidance: turning my amorphous thoughts into a thesis-worthy proposal and, after I had no luck acquiring a director on my own, pointing out that one of my favorite professors would be a great fit.
To my thesis director Andrew Tirrell – thank you for reminding me to keep a manageable scope for my thesis. I appreciate your encouragement and perspective – they came at the right time and in the right measure.
To my thesis coach Susan Bernhard – I am so lucky to be one of the many, many beneficiaries of your counsel and friendship. You know how, when, and where to nudge.
To Ann Reisenauer and Dick Simpson (and by extension Chaco and Luna) – thank you for being my friends, welcoming me into your beautiful home, and inspiring me to enjoy life, explore the world, and pursue my passions. I will continue to try to repay my debt of gratitude.
Special mention goes to the San Francisquito Creek Joint Powers Authority and the dedicated stakeholders who’ve committed to making improvements to the watershed.
There are several individuals with whom I discussed my research, and I appreciate the perspectives each shared. Their input has contributed to the vibrancy of my understanding of the history and present state of the watershed.
I am grateful for my family, friends, coworkers, and the motley collection of individuals who offered their support to me throughout my thesis process. Thanks for your encouragement!
iv Table of Contents
Acknowledgments...... iv
List of Tables ...... viii
List of Figures ...... ix
Definition of Terms...... x
I. Introduction ...... 1
Research Significance and Objectives ...... 2
Background ...... 3
Water in California ...... 3
Bay Area Water Supply ...... 7
Perception and Social Justice ...... 11
Watershed Sustainability ...... 14
Composite Watershed Sustainability Metrics ...... 16
WSI ...... 18
Opportunities to Improve the WSI ...... 23
Water Footprint ...... 26
Watershed Management and Integrated Water Resource Management ....27
The SFC Watershed ...... 28
Research Question, Hypotheses and Specific Aims ...... 34
II. Methods ...... 36
Application of the WSI to SFC Watershed – Data Acquisition...... 36
v Hydrology ...... 36
Environment ...... 41
Life ...... 43
Policy ...... 45
Application of the WSI to SFC Watershed – Calculation ...... 46
Evaluation of Indicators ...... 47
Inter-basin water transfers...... 47
Social Justice ...... 48
Efficiency ...... 49
Resilience ...... 52
Model Development...... 52
Model Application to the SFC Watershed ...... 53
III. Results ...... 55
SFC WSI ...... 55
SFC WSV...... 56
WSV Model ...... 56
SFC Watershed Sustainability Analysis ...... 57
IV. Discussion ...... 59
Interpretation and Significant Implications of Results ...... 59
Specific Aims ...... 59
Hypotheses ...... 63
Results in Context ...... 64
Opportunities for Methodological Improvement ...... 65
vi General Observations ...... 65
Overlooked assumptions ...... 67
Unintuitive consequences ...... 69
Conclusions ...... 69
Contributions...... 70
Research Limitations ...... 70
Recommendations for Future Research ...... 71
Model improvements ...... 71
Groundwater basin sustainability ...... 72
Appendix 1 Description of WSI Parameters, Levels, and Scores...... 74
Appendix 2 Social Justice and Equity Indicators ...... 77
References ...... 78
Ancillary Appendix 1 Q-values for WQI Calculations...... 85
Ancillary Appendix 2 WSV for Selected Basins (using WSI Results) ...... 90
vii List of Tables
Table 1 Indicators and parameters of the WSI ...... 20
Table 2 Mapping WSI parameter value to score ...... 22
Table 3 Allocation disparity in the SFC watershed ...... 32
Table 5 SFC WSI: parameters values and indicator scores ...... 56
viii List of Figures
Figure 1 San Francisco regional water system ...... 7
Figure 2 Bay Area wholesale suppliers ...... 8
Figure 3 BAWSCA (a) members and (b) supply by source ...... 9
Figure 4 Interconnected dimensions of sustainability ...... 15
Figure 5 WSI parameter score assignment ...... 21
Figure 6 Water infrastructure in California ...... 24
Figure 7 SFC watershed land ownership ...... 29
Figure 8 SFC flood protection projects ...... 30
Figure 9 SFC watershed and alluvial fan ...... 31
Figure 10 SFC watershed satellite map these are beautiful figures ...... 34
Figure 11 Equity indicators ...... 50
Figure 12 SFC WSV ...... 57
ix Definition of Terms
$PCD: Dollars per capita per day
AIMS: Annual Indicator and Measures
Acre-foot: Volume of one acre filled to a depth of one foot, or 435.6 CCF
ACWD: Alameda County Water District
AF: Acre-foot
Basin (see Watershed)
BAWSCA: Bay Area Water Supply and Conservation Agency
BMP: Best management practice
BOD5: Five-day biochemical oxygen demand
CCF: Centum cubic feet
CCWD: Contra Costa Water District
Centum Cubic Feet: 100 cubic feet (which is equivalent to 748 gallons, or 0.0023 AF)
CPUC: California Public Utilities Commission
CWC: Community Water Center
CWS: California Water Service
EBMUD: East Bay Municipal Utilities District e.g.: exempli gratia (literally: “for the sake of example”, commonly interpreted as: “for
example”)
EPI: Environmental Pressure Index
FY: Fiscal Year
GIS: geographic information system; a framework for gathering, managing, and
x analyzing data
GPCD: Gallons per capita per day
GSA: Groundwater Sustainability Agency
HDI: Human Development Index
HELP: Hydrology, Environment, Life, Policy
HELPERS: Hydrology, Environment, Life, Policy, Efficiency, Resilience, Social Justice i.e. id est (literally: “that is”, also commonly interpreted as: “in other words”)
Individual Supply Guarantee: Allocation of water from SFPUC
Intertie: Interconnection permitting passage of water between systems
ISG: Individual Supply Guarantee
IWRM: integrated water resource management
JPA: Joint Powers Authority
MGD: million gallons per day
µS: micro Siemens
MID: Municipal Improvement District
MMWD: Marin Municipal Water District
NB: nota bene (literally: “note well”, commonly interpreted as: “note that”)
NTU/JTU: Nephelometric Turbidity Unit/Jackson Turbidity Unit
O2: oxygen pH: potential of hydrogen, indicates how basic or acidic a solution is
PPIC: Public Policy Institute of California
R-GPCD: residential gallons per capita per day
SCVWD: Santa Clara Valley Water District
xi SFC: San Francisquito Creek
SFPUC: San Francisco Public Utilities Commission
SGMA: Sustainable Groundwater Management Act
UNESCO: United Nations Educational, Scientific, and Cultural Organization
Watershed: an area bound by a divide (generally a ridge) which drains to a stream or
water body
WRM: water resource management
WSI: Watershed Sustainability Index
WSV: Watershed Sustainability Visualization
WQI: Water Quality Index
Zone 7: Zone 7 Water Agency
xii Chapter I
Introduction
Water availability has social, ecological, and economic benefits. On a global scale, sustainability considers how both current and future generations meet their needs.
When applied to watersheds on a local level, sustainability analysis can reveal vulnerabilities and risks that effective watershed management may be able to mitigate.
Appropriate actions taken in response to unsustainable conditions should increase the aggregate benefits to all stakeholders over the long-run.
Society’s relationship with the resources on which it depends reflects its sustainability. In the case of water, western states bear the dual burden of unfavorable circumstances associated with limited resources and the need to reform a long-standing legacy of wasteful practices. Here, the value of my proposed research is explained in terms of the local context, needs, and challenges present in California.
Given the recent and persistent threat of drought in California, water issues have ascended to an unprecedented level of importance. The agricultural sector, which fuels a substantial portion of the state’s economy and produces food for domestic and international consumption, relies upon vast quantities of the west’s limited water resources. The commercial and industrial sectors also compete for water alongside the public which depends on water for domestic use as well as outdoor irrigation. And lastly, the environment, the health of which supports all of the aforementioned activity, warrants its share of the resource that it provides to all of the other stakeholders in the state. Research Significance and Objectives
The intent of this research was three-pronged. Primarily, the results shed light upon, and fill, a gap in the toolkit used to assess watershed sustainability. In addition, this research enables a better understanding of the health of the San Francisquito Creek
(SFC) watershed in terms of sustainability. And ultimately, the results inform watershed management activities intended to improve sustainability.
Many controversial issues involve water rights and how water resources and watersheds are managed. Although it is in society’s long-term interest to sustainably manage the limited water resources available, well-intentioned efforts may fail to have any meaningful impact without effective tools to adequately understand and quantify watershed sustainability. This research will help make the currently available diagnostic tools more robust, allowing us to understand the areas where watersheds are most vulnerable and assess the impact of management efforts aimed at improving conditions.
The current diagnostic toolkit includes an established Watershed Sustainability
Index (WSI) which can help determine a watershed’s health if available water originates and is utilized within the watershed’s boundary (Chaves & Alipaz, 2007); however, it fails to offer a means to assess watershed health and the regional use of water that is not restricted by these conditions. The results of this research help address this need. In addition, this research broadens the lens of the metric to include indicators not previously contemplated.
The implications of this work impact both those interested in understanding watershed ecosystem health as well as those actively involved in managing it. A robust watershed sustainability metric that enables drill-down into the relevant factors facilitates
2 identification of problem areas and evaluation of the effectiveness of management efforts’ ability to improve sustainability.
My objectives were:
• To identify and, to the extent that improvements are clear, address shortcomings
of the current WSI
• To analyze how the current WSI could be adapted to provide a more useful
framework for watersheds, like SFC, in which imports and exports warrant
consideration
• To determine if the refined watershed sustainability metric could be applied to the
SFC watershed (for the purpose of validating and testing it)
• To evaluate watershed management activities’ effectiveness based on knowledge
arising from the refined watershed sustainability metric.
Background
The definition of watershed sustainability as presented in the existing literature serves as the foundation for understanding shortcomings in the current analytical approaches. Moreover, it suggests options for developing a more robust approach to watershed sustainability analysis.
Water in California
California’s relationship with water offers compelling insight into its sustainability challenges. The state boasts a growing population currently at 39 million and slated to surpass 50 million by 2050 (Public Policy Institute of California, 2018).
3 The state’s economy also recently surpassed France as the sixth largest in the world
(World Bank, 2016). With the third largest land area in the United States, California spans diverse landscapes and climates, the most dominant of which is the Mediterranean
Climate in the Central Valley. Although less predictable in the age of climate change, water availability represents one of the greatest concerns for numerous stakeholders both within and outside the state. An abundance of water results in devastating floods while water scarcity resulting from drought or overuse compromises everyone’s ability to meet their needs. These diametrically opposed situations are further compounded by climate change which intensifies the amplitude and frequency of drought and flood, and in doing so exposes the social, environmental, and economic vulnerabilities of the state.
Arguably, California has the most extensive water infrastructure in the world (Austin,
2015). In most parts of the state, precipitation is limited to the winter season (November through April). However, multiple systems consisting of pipes, tunnels, canals, reservoirs, dams, pumping stations, power plants, fish hatcheries, and siphons work in concert to meet societal needs for water. As expected, infrastructure projects are accompanied by high, capital costs as well as high, ongoing expenses for operation and maintenance of their facilities. Although late in coming, environmental considerations are now being weighed in decisions concerning hydrologic alterations.
Understanding the state’s non-local water supply and systems is informed by its history. In many ways, Western development was fueled by water availability. In the arid west, reliable water typically resulted from generous promises and costly infrastructure projects effectively transforming arid regions into desirable economic centers in which water was readily available. Water rights mimicked property and
4 mining rights and the power of those that held them ensured that they would perpetuate despite their incoherence (Cantú, 2015). The West’s insatiable thirst for water became problematic once its inhabitants realized that an unlimited water supply was not guaranteed.
Although different, supply and demand issues pose similar challenges for water and energy. Sources of freshwater supply naturally fall into two broad categories: groundwater and surface water. However, it’s worth noting that technological innovation and need have fostered the development of other supply alternatives, including water treatment plants ranging from desalination (used in wealthy coastal areas that otherwise lack adequate freshwater supply) to recycling and purification. The products of the treatment processes may be tailored to specific uses based on certain requirements (e.g. standards for drinking water vs. industrial or agricultural), allowing for different grades of water. Although water treatment often renders water supply from different sources incompatible, all drinking water is generally lumped into the same category: potable.
Unlike the highly perishable commodity of electricity, water exhibits non- perishable characteristics. This important distinction allows for storage and conveyance over great distances, but does not guarantee its efficiency. Water readily evaporates, seeps into the ground, and poses logistical challenges due to its density. Its conveyance involves expensive infrastructure and significant energy. According to a 2005 California
Energy Commission report, transportation and treatment of water, treatment and disposal of wastewater, and the energy used to heat and consume water account for nearly 20 percent of the total electricity usage in the state (California Energy Commission).
5 Like energy, water conservation and efficient use of water resources can delay the need to tap into new sources of supply. The limited sources of supply are rapidly being exploited and exhausted. To complicate matters, contaminants threaten water quality, necessitating treatment to meet increasingly more stringent standards.
Knowing that developed water has a cost and is limited in supply, its use matters.
How much developed water is put to “beneficial use”? What is “beneficial use”? How much consumption is one-time use? How much developed water returns to the watershed? As viable water supply options become scarcer, water managers may begin to more carefully contemplate questions like these. Would they consider a tax on certain types of consumption? Or might they, like Australia, consider the implementation of water markets that differentiate between water grades driven by end-use (such as recycled water for irrigation)?
Groundwater extraction has costs both in the electricity to pump as well as diminished capacity when overdrafting results in land subsidence permanently reducing aquifer storage capacity. Water providers throughout California increasingly find themselves evaluating the possibility of practices like groundwater recharge, desalination, recycling (purification of wastewater effluent), and water banking.
Inasmuch as the country depends on food grown in California, the state itself depends on water from external sources. Furthermore, the majority of Californians counts on water supplied from outside its local watershed. For example, San Francisco and many communities of the Bay Area depend on an aqueduct that conveys water 167 miles from Yosemite National Park to the San Francisco Bay Area. In California, local water is the exception, not the rule, even outside urban centers.
6 Bay Area Water Supply
The regional water supply system operated by the San Francisco Public Utilities
Commission (SFPUC) collects water (~85%) from the snow-fed Tuolumne River in the
Sierra and wheels it to residential, commercial, and wholesale customers in the Bay Area
(SFPUC, 2017). The infrastructure used to convey the water is collectively referred to as the San Francisco Regional Water System (Figure 1). Despite its utility, the impounding of water behind the O’Shaughnessy Dam (and many others) is also not without controversy as groups call for the removal of dams to restore rivers.
Figure 1. San Francisco regional water system. 85% of SFPUC’s water is impounded at Hetch Hetchy Reservoir. Large pipes convey the water from the reservoirs to customers in the Bay Area (SFPUC, 2017).
The Bay Area Water Supply and Conservation Agency (BAWSCA) coordinates the water agencies that rely on both local supplies as well as those that are imported via the San Francisco Regional Water System (BAWSCA, n.d.). The BAWSCA members
7 on the peninsula primarily rely on water imports from one of two agencies: the SFPUC and the Santa Clara Valley Water District (SCVWD); although some agencies are able to receive supply from both wholesalers through interties (Figure 2).
Figure 2. Bay Area wholesale suppliers. Two wholesale suppliers serve the San Francisco Peninsula: SFPUC and SCVWD (Brown and Caldwell, 2017).
Agencies that rely on a diverse supply portfolio are less vulnerable to uncertainties associated with supply availability. In addition to imported supply,
BAWSCA members may also rely on groundwater, surface water, or recycled water
8 supplies (Figure 3). However, some member agencies rely exclusively on imported water from a single wholesale supplier.
Water agencies need resilient supply portfolios that can respond to changes in demand as well as disruptions in sources. Absent a diverse supply portfolio with
Figure 3. BAWSCA (a) members and (b) supply by source (Gonzalez & Ajami, 2015). Legend 1 Alameda County Water District 13 Mid-Peninsula Water District 2 City of Brisbane 14 City of Millbrae 3 City of Burlingame 15 City of Milpitas 4a CWS – Bear Gulch 16 City of Mountain View 4b CWS – Mid-Peninsula 17 North Coast County Water District 4c CWS – South San Francisco 18 City of Palo Alto 5 Coastside County Water District 19 Purissima Hills Water District 6 City of Daly City 20 City of Redwood City 7 City of East Palo Alto 21 City of San Bruno 8 Estero Municipal Improvement District 22 San Jose Municipal Water System – North 9 Guadalupe Valley MID 23 City of Santa Clara 10 City of Hayward 24 Stanford University 11 Town of Hillsborough 25 City of Sunnyvale 12 City of Menlo Park 26 Westborough Water District
9 contingencies for source disruptions, water agencies’ risk profile becomes unacceptable.
The water crisis in Cape Town, South Africa provides a sad example of the dangers of dependence on a single source of supply.
Various stakeholders have become increasingly vocal about water management.
Environmentalists focus on impacts to the ecosystem, homeowners call upon their elected officials to address flood risks, and developers continue to demand more resources to supply new housing stock. As a result of this, various attempts at regulation have taken shape to remediate the situation.
Today, joint power authorities that focus on watershed management proliferate.
Since waterways often divide community and jurisdictional boundaries, the need for new regional governmental agencies continues to grow, with their boundaries coincident with that of their respective watersheds. And although initially motivated by concerns about liability associated with waterways, joint power authorities are increasingly seeing waterways as important assets. The joint power authorities and watershed managers focus on ecosystem, social and recreational needs, as well as emergency response plans.
In short, these agents are responsible for ensuring watershed sustainability. They devote considerable resources to projects but do not always have visibility into the overall impact of those actions on the watershed’s overall health. In order to determine the effectiveness of their actions or to justify future activities, it seems logical that they should know that they will achieve meaningful and desirable results with high positive impact.
10 Perception and Social Justice
Reisner’s classic book, Cadillac Desert, published in 1987, offered a stark picture of water in the West. In the 30 years since its publication, despite its advances,
California seems to have perfected the art of trading one problem for another in its attempts to engineer a solution to one problem and, in turn, create another.
“I’ll believe there’s a drought in California when the golf course greens are brown” (D. Erskine, personal communication, 2015). In the height of the most recent drought, a long-time California resident told me that he didn’t believe there was a drought. Apparently the dwindling capacity of reservoirs and the subsidence resulting from overdrafting of the aquifers in the Central Valley was not concerning to him. But, he had a good point. How could it be that, despite the worst drought in the state’s history,
California still had lush green golf courses in the desert?
Moreover, how could a community with a lush green golf course be situated beside another community that had (and continues) to rely on water trucks because its wells have gone dry? This stark contrast would be completely absurd were it not reality for the residents of East Porterville.
It didn’t help matters that homes in the directly adjacent, slightly wealthier town of Porterville had running water from the town’s municipal water system. Perhaps the most glaring example of this could be found on the city boundary: locals would take showers at Igelsia Emmanuel in East Porterville, while directly across the street, in
Porterville, was a patchy but green golf course (Lurie, 2015).
A veneer of abundance belies the tenuous relationship between Californians and their water. Although many Californians have adopted water conservation as a way of
11 life, others remain blissfully ignorant of the water challenges that the state faces. To a certain extent, “Brown is the new Green,” and many Californians have learned to recognize waste in the culture of “convenience.” Incentives have been put in place, educational campaigns have been successful, alignment between government agencies, and a healthy dose of social pressure seems to have given many the nudge they need to make behavioral changes. However, it took until 2014 for the state to pass legislation to manage groundwater. Until then, California was the only western state without laws to preserve and protect its groundwater resources.
According to the Community Water Center, more than one million Californians have unreliable access to safe and affordable drinking water (2016). Here, “safe water” is defined as that which is available in the quantity to meet human needs and of the quality to maintain health. Marginalized communities (predominantly low-income and Latino) are disproportionately affected.
The right to water is uncontested; however, water service does have a cost. There is a school of thought that water should be “free.” However, as previously explained, the cost of the infrastructure and maintenance to provide water service is quite expensive, consequently tap water is not free.
Although water may be relatively cheap for some, others devote a significant portion of their income (5-10%) in order to pay for safe drinking water. Since most household taps and fixtures don’t measure water flow or indicate how much water use costs, most customers rely on a water bill that comes a month or more in arrears – making it hard to course-correct. Furthermore, many members of disadvantaged communities often find themselves in shared living situations where the number of occupants is high
12 relative to the average household size. One negative consequence of inclined block rate structures that promote conservation is that they result in higher water charges for low- income, high-occupancy living situations. Also, for those living in communities with small water systems that are not adequately maintained, residents may also be forced to purchase bottled water to get safe water. Bottled water costs about 300-2000 times more than most pay for their water service (Boesler, 2013).
Urban water pricing lacks transparency, is unintuitive, and downright complicated. Rates may or may not provide signals to consumers. This is due in part by the reality that prices are not driven by markets nor constraints. Rates for public agencies are governed by Proposition 218 which stipulates that one group of customers cannot subsidize another, by dictating that the fee for a service must be proportional to its cost.
As such many public agencies are reluctant to impose a rate design that might otherwise incentivize water conservation. Meanwhile, the CPUC which approves rates for regulated water utilities, has recently mandated that water companies provide conservation incentives to its customers through a decision in its Balanced Rates proceeding (CPUC, 2016).
Considering how rate design impacts the most vulnerable members of the population reveals other embedded iniquities of water costs as well as more social justice issues. Income determines both where and how you can afford to live in the Bay Area, just as it does in many places throughout the country and the world. And although location may determine an individual’s water rates, living arrangement may dictate how much an individual’s (or his/her family’s) water costs. It is not uncommon for 10-40 people to be hot-bunking in a modest sized house in East Palo Alto. Although these
13 individuals may have less expensive water rates than residents of nearby Woodside, they may pay a larger fraction of their income because (a) their income is about a tenth of their hillside neighbors and (b) their water usage may be charged in a higher tier rate. These unintuitive findings often elude common metrics and sustainability analysis.
Watershed Sustainability
When it comes to freshwater supply, water and watershed sustainability are inextricably linked: the sustainability of one depends on that of the other. As a general definition, sustainability is the capability of present and future generations to meet their needs. The definition applies on a global scale and to species other than our own (Fulton and Shilling, 2015).
Although an exhaustive discussion might take into consideration the complementary ground-water watersheds, I will focus on surface-water watersheds and the hydrologically connected water within the superficial watershed boundary (Winter,
Harvey, Franke, & Alley, 1998).
Beyond the formal definition of sustainability, it’s useful to frame sustainability in more tangible pieces. Here I will discuss eight dimensions (Figure 4). The first and most straightforward dimension is hydrology. Simply put: reliable water relates, in part, to hydrological aspects including accessibility, quantity and quality. The second dimension of water sustainability is related to resiliency or ability to adapt. Assuming that conditions are constant leads to a false sense of security and inadequate preparation for a future wrought by climate change. Moreover, absence of alternative options indicates vulnerabilities. The third dimension of water sustainability is the environment or
14 ecosystem. And the fourth is economic considerations, including everything from the cost and price of water to the way in which it may be subsidized.
Beyond these four core components are softer and less-intuitive, overlapping dimensions of watershed sustainability: education, regulation, equity (or social justice), and efficiency. Watershed sustainability should be analyzed across all of its dimensions
– they are integral, albeit often taken piecemeal.
Social Justice Economy
Resiliency
Education
Efficiency
Policy
Environment
Hydrology
Figure 4. Interconnected dimensions of sustainability. Dimensions of sustainability interact with one another. For example, social justice may impact resiliency, policy, education, and economy and be influenced by policy, hydrology, and education (by author).
15 Composite Watershed Sustainability Metrics
Ideally an analysis of watershed sustainability should parallel the three main pillars of sustainability: social, environmental, and economic. However, coverage of these pillars is paramount to alignment with them. Instead, the desirable and undesirable characteristics of composite watershed sustainability metrics need to be evaluated in order to inform the evaluation of those that are currently available.
There are numerous watershed assessment tools based on indicators. Previous reviews have explored the selection of indicators, weighting of indicators, robustness of analysis, and interpretation of the final metric, for the purpose of aiding others who wish to customize existing indices for their applications or for developing new metrics
(Juwana, Muttil, & Perera, 2012). This work facilitated my own evaluation of metrics and informed the development of a sustainability tool that considers inter-basin water transfers.
First the appropriate unit of analysis (i.e. the spatial boundaries concerned with the unit and scale) was evaluated. The watershed is a natural choice as it establishes natural boundaries that are in concert with hydrology. Furthermore, the basin boundary may also delineate the management area, that is, where actions are taken that impact the watershed. Note that there may be limits to the scale at which a given analysis may be applied, but that aggregating sub-basin (or micro watershed) results may provide regional specificity within a given watershed. By extension, temporal factors that enable the metric to quantify sustainability during a specific interval were considered. It is also worth noting the value of metrics that incorporate perspective – beyond just a snap shot – these metrics provide an indicator of the extent to which a situation is changing over time
16 or as a result of something else. For example: pressure, state, response parameters are used for each indicator. Parameters can be thought of as factors of an indicator. Pressure may measure variation in the indicator values over the history of measurement. State can measure the value of the indicator during a specified time. Response, in contrast to pressure, may measure changes in the indicator value during a specified period of interest.
In my search for a metric, I also acknowledged the desire to quantify sustainability, both in order to objectively benchmark the metric, but also for comparison within a given watershed or among different watersheds.
The methods used to develop the composite watershed metric were equally important. Data availability, straightforward calculations, and understandable results were prime considerations.
The strength of conclusions that can be drawn from simple metrics may be limited. For example, imagine trying to use height measurement as an indicator of someone’s health? Wouldn’t there be additional data you’d want? Here I tried to find the sweet spot – telltale data that could be leveraged to draw powerful conclusions.
Similarly, I recognized the need to balance the ability to get data or perform calculations with simplicity.
Although informative, an approach using sophisticated math, such as finite element analysis, would involve numerous assumptions and would likely put off otherwise interested practitioners from attempting the analysis, if not for its complexity, but also for its steep learning curve, and somewhat esoteric, if not inaccessible partial differential equations. I personally would like to avoid too many Greek symbols and
17 having to explain Eigen values in my metric.
Also, I’d like to think of the audience to whom results are communicated.
Knowing that local stakeholders are laypeople, information: data and results should be accessible, understandable, and easy to communicate. This applies to decision-makers as well.
Most composite watershed sustainability metrics do not provide basin-specific insight. The two noteworthy exceptions are the Watershed Sustainability Index (WSI) and a metric that aims to evaluate the sustainability of river basins subjected to an inter- basin water transfer project. However, the method employed in the latter assumes a one- to-one relationship between recipient and source watersheds (Kefayati, Bahram, Azadeh,
& Babazadeh, 2018). Thus, my model will build upon the simple, yet robust, WSI foundation.
WSI
Motivated by the desire to assess the efficacy of basin-specific watershed management efforts, I wanted to have a basin-specific indicator that integrates the aforementioned sustainability dimensions. Although numerous, the current indicators tend to focus on only a subset of the sustainability dimensions, and with one noteworthy exception, fail to offer basin-specific insight (Brown & Matlock, 2011).
The WSI assesses watershed sustainability with respect to watershed management efforts and most-effectively incorporates several of the sustainability dimensions previously discussed. The WSI has been applied to numerous watersheds around the world (Catano et al., 2011; Chaves, 2011; Cortés et al., 2012; Firdaus, Nakagoshi, &
Idris, 2014; Kretschmer, Wendt, Oyarzun, & Chaves, 2011; Maynard, Nascimento, Cruz,
18 & Gomes, 2017; Oliveira de Castro, Santos Loureiro, Vieira Santos, Silva, & Bonino
Rauen, 2017; Senent-Aparicio, Pérez-Sánchez, García-Aróstegui, Bielsa-Artero, &
Domingo-Pinillos, 2015). The basis for its development was a pre-existing UNESCO framework, HELP. HELP, the brainchild of UNESCO’s International Hydrology
Program, includes hydrology, environment, life, and policy. As shown in Table 1, the
WSI looks at each of these four variables across three parameters (Chaves & Alipaz,
2007). A given indicator is the average of its parameter values and the WSI is the average of the indicator values.
Parameter values are grouped into defined levels and assigned a score. Defined patterns (e.g. E-I-1) are shown in Figure 5 and mapped to their respective parameters in
Table 2. Notable features include: (A) nine distinct patterns; (B) values may be divided into even or uneven intervals, denoted by the letter E or U, respectively; (C) the score either increases or decreases with the value, denoted by the letter I or D, respectively; (D) in some instances, values are numeric, in others they are categorical; (D) parameter score may take one of five values (e.g. 0.00, 0.25, 0.50. 0.75, 1.00).
In the case of the quantitative hydrological indicator, it is assumed that the per capita water availability is based upon water originating from within the basin. It should be noted that this particular assumption is not valid for most urban watersheds, nor for those watersheds, located in places with water constraints, that may rely on imported water supplies.
In addition to providing a beachhead for my research effort, the WSI’s authors also recommend the use of the Habitat Conservation Trust Fund’s guidelines for selection of indicators. The bulleted guidelines that follow, set forth criteria intended to make the
19 Table 1. Indicators and parameters of the WSI. Parameters* Pressure State Response Indicators Hydrology Variation in the Basin per Improvement in basin per capita capita water water-use water availability efficiency in the availability in (long-term period analyzed the period average)
Variation in the Basin BOD5 Improvement in basin (long-term sewage biochemical average) treatment/disposal oxygen demand in the period (BOD5) in the analyzed period analyzed Environment Basin Percent of Evolution in basin Environment basin area with conservation Pressure Index natural [percent of (EPI, for rural vegetation protected areas, and urban) in the best management period analyzed practices] in the period analyzed Life Variation in the Basin Human Evolution in the basin per capita Development basin Human income in the Index Development period analyzed (weighted by Index in the county period analyzed population) Policy Variation in the Basin Evolution in the basin Human institutional basin’s Integrated Development capacity in Water Resource Index - Integrated Management Education in the Water expenditures in period analyzed Resource the period Management analyzed
20 Key: Parameter Score Value 0.00 0.25 0.50 0.75 1.00
(E-I-1)
-20 -10 0 10
(E-I-2)
-10 0 10 20
(E-I-3)
Very Poor Poor Medium Good Excellent
(E-I-4)
1,700 3,400 5,100 6,800
(U-I-1)
5 10 15 20 25 30 35 40
(U-I-2)
0.50 0.55 0.60 0.65 0.70 0.75 0.80 0.85 0.90
(E-D-1)
-10 0 10 20
(U-D-1)
0 5 10 15 20
(U-D-2)
1 2 3 4 5 6 7 8 9 10
Figure 5. WSI parameter score assignment. The values of the corresponding parameter, shown in the graphic map to one of five parameter scores which are in turn used to calculate the WSI (by author).
21 Table 2. Mapping WSI parameter value to score. Parameters
Pressure State Response
Hydrology (quantitative) E-I-1 E-I-4 E-I-3 (qualitative) E-D-1 U-D-2 E-I-3
Environment U-D-1 U-I-1 E-I-2
Life E-I-1 U-I-2 E-I-2
Policy E-I-1 E-I-3 E-I-2
resultant metric useful.
• Available: the indicator data should be available and easily accessible. They
should be collected throughout the watershed, published on a routine basis, and
made available to the public.
• Understandable: indicators should be easily understood by a diverse range of
nontechnical audiences.
• Credible: indicators should be supported by valid, reliable information, and
interpreted in a scientifically defensible manner.
• Relevant: indicators should reflect changes in management and in activities in the
watershed. They should be able to measure changes over time.
• Integrative: indicators should demonstrate connections among the environmental,
social and economic aspects of sustainability. (Chaves & Alipaz, 2007, p. 885)
The creators of the WSI intended that it would serve as a universal index capable of being applied to any basin for which the data is available. And although conceptually flexible, allowing for weighting the indicators differently depending on consensus, the
22 WSI does not adequately register enough dimensions to allow for the analysis of watersheds in which water imports or exports warrant consideration. Its application is generally limited to evaluation of basins in the countries for which data may be scarce, but could be incredibly useful if refined to be able to take into consideration characteristics of basins in the western United States, in particular, California.
If I were to conceptualize an analytical watershed boundary around all of the watersheds that are interconnected via interties, I’d see that many large swaths of the state of California would fall into a single boundary, due in large part to water transfers made possible by state, federal, and local engineering projects (Figure 6). The San
Francisco Peninsula is no exception. However, it is worth noting that an all-inclusive watershed boundary poses an analytical challenge which beyond being untenable would lead to generalized conclusions that are overly broad given the specific issues of the constituent local watersheds. In the interest of reaching meaningful conclusions that are relevant to local stakeholders I aim to retain watershed specificity.
Opportunities to Improve the WSI
For all its strengths, the WSI also has its shortcomings. With the motivation to improve the metric, I consider a few weaknesses. First, in its methodology, the WSI does not discuss what to do if data are unavailable, missing, or cannot be calculated. There is no guidance provided – it is unclear whether a particular indicator should be either dropped from the calculation or assigned an arbitrary value. As a practical matter, at the very least, you’d need to adjust the weighting if a value were unavailable. However, there is limited transparency in the results if weighting is altered from the default recommendations.
23 Figure 6. Water infrastructure in California. Many large watersheds are hydrologically interconnected both with and outside the state of California (Silverman, 2015).
With respect to quantity, there is no distinction between economic and physical water scarcity. This is an issue for underprivileged consumers. With respect to
24 hydrological indicators, taking annual data masks hydrological variability. Depending on whether or not water can be impounded in a reservoir, this may mask stresses on a watershed.
Also assumptions about historical patterns persisting into the future may not be valid. Impounding water in a storage reservoir to hedge against seasonal variation in precipitation may not be sustainable if a new norm comes into play. California may be entering an age in which the infrastructure, designed and constructed 50 or more years ago, was conceptualized with certain assumptions that may no longer be valid. For example, the assumption that precipitation falls as snow and slowly melts to fill surface reservoirs during the spring may not be valid going forward.
In addition, data sources may influence results. Most indices rely on secondary data. Relying on readily available data, may not be specific to the exact area of interest, and different sources often provide wildly different values.
With respect to basins and sub-basins, it may also be invalid to suggest that sub- basins can be aggregated to a larger basin up to 2,500 square kilometers for the WSI.
Furthermore, diluting information with an average (weighted or otherwise) masks important details behind a single numerical index that may be counterproductive. And a single numerical index may undermine the intrinsic value of the indicators by muting the variation, specifically, any outliers.
Also, the index does not use non-collinear factors. Many of the indicators share similar values (be it between the pressure, state, and response parameters or between the indicators themselves).
25 Weighting and evaluation of some factors is subjective. The methodology suggests that unless there’s a strong reason to change these weightings, they should be equal. However, it’s worth noting that, this discretionary decision may have perverse consequences. Depending on the situation, manipulation of the weighting may alter the outcome in such a way that it appears either more bleak, or more favorable.
Lastly, limiting scores to five values seems unnecessary. It limits the combination of possible outcomes. As a corollary, most WSI values fall within a small range.
Approximately 95% of results indicate intermediate sustainability. Undifferentiable results make it difficult to use the information. Decision makers may find it difficult to determine what to act upon and how to measure the effectiveness of their actions.
Water Footprint
Water footprint, like the concept of carbon footprint, is an accounting system; in essence it tracks the amount of water to produce, supply, and deliver goods and services to a specific location, person, or group. Unlike the WSI, the water footprint is, to a certain extent, watershed agnostic.
Water footprint accounting does not necessarily require the imposition of boundaries – geopolitical, or those of a watershed. However, by that same token, the absence of watershed-specific information dilutes the applicability of the analysis to specific watersheds.
A water footprint provides an accounting of all of the water necessary to support a given lifestyle – both direct and indirect uses: as an example, water to drink or the water involved to grow food or transport goods from where they were produced to where they
26 are consumed. Although water footprint is dependent on habits and, to a large extent, location, it is not typically examined at the watershed level.
Conceptually, water footprint draws the distinction between consumptive use of water – that is, that which makes use unavailable for other uses – and nonconsumptive use. This accounting convention then looks at three types of water, which have been associated with the colors blue, green, and grey, as follows:
• Blue water: includes surface and groundwater that are developed and managed for
human use;
• Green water: includes the water that exists in the environment that is not
developed for human use;
• Grey water: (N.B. not graywater): indicates the level and degree of contamination
resulting from processes that humans engineer – it is the equivalent volume of
water necessary to dilute that contamination to a level that is no longer harmful
(Fulton & Shilling, 2015).
In combination, these three dimensions of the water footprint help shed light on a different approach to analyzing water sustainability.
Watershed Management and Integrated Water Resource Management
Watershed management primarily refers to the actions taken within a watershed to sustainably distribute its resources. This may include policy, projects, and programs aimed at improving the features that impact communities (human, flora, and fauna) within the watershed’s boundaries. Similarly, Integrated Water Resource Management
(IWRM) focuses on sustainability; however, it is not bound by watershed limits and it
27 focuses on developing and managing water, land, and resources in a way that equitably addresses both economic and social welfare without degrading the ecosystem.
Both watershed management as well as IWRM may be assessed qualitatively or quantitatively with respect to their respective over-arching goals. Moreover, both should have tangible outcomes which can be deemed successful or unsuccessful, necessary or unnecessary, and effective or ineffective. And given the financial cost of undertaking either watershed management or IWRM activities, it behooves the public to understand which outcomes deliver meaningful results relative to the investment.
The SFC Watershed
The area of interest, the San Francisquito Creek (SFC) watershed, is situated on the San Francisco peninsula, snuggled up against the eastern slope of the Santa Cruz
Mountains, sprawling 45 square miles down to the San Francisco Bay (Herman,
Torregrosa, Kapla, & Hoong, 2007). Significant portions of the watershed are owned by the city or county, federal government, Midpeninsula Regional Open Space District,
Peninsula Open Space Trust, Jasper Ridge Biological Preserve, California Water Service and private parties (Figure 7).
The area includes Searsville Lake, Felt Lake, Lagunita Lake, and Bear Gulch
Reservoir (each of which is formed by a dam) as well as various natural habitats, and five communities from two counties, Palo Alto and Menlo Park in Santa Clara County, and
East Palo Alto, Portola Valley, and Woodside in in San Mateo County. Long-term precipitation is approximately 15 inches to 40 inches annually at lower and upper reaches of watershed, respectively (Metzger, 2002).
28 Figure 7. SFC watershed land ownership. Large swaths of SFC watershed are owned by various public and private entities (Cohen, 2002).
Although conservation and management of the watershed officially falls under the auspice of the Santa Clara Valley Water District, the SFC Joint Powers Authority
(SFCJPA) actually oversees the area and serves the communities (Materman et al., 2017).
The SFCJPA’s current work include three major projects to “reduce a proven flood threat, enhance ecosystems and recreational opportunities, and connect communities (San
Francisquito Creek Joint Powers Authority, 2018).” Two projects (Figure 8) are related to the infrastructure around the creek. The first focuses on the portion of the creek upstream of Highway 101, while the second targets the portion of the creek that runs from Highway 101 to the San Francisco Bay. SFCJPA’s third project is its Strategy to
Advance Flood Protection, Ecosystems and Recreation along the Bay (known as the
29 SAFER Bay Project), which evaluates infrastructure alternatives to protect Bayshore communities from extreme tides with sea level rise, and enhance shoreline ecosystem and access.
Figure 8. SFC flood protection projects (San Francisquito Creek Joint Powers Authority, n.d.).
SFC watershed comprises several subwatersheds and is transected by the San
Andreas Fault. Historically, throttled where hills meet the flatlands (point A, Figure 9), the SFC deposited sediment in an alluvial fan. Over time the course of the SFC became deeper. During floods, the SFC would overflow its banks depositing sediments that
30 Figure 9. SFC watershed and alluvial fan. Historical depiction of watershed and alluvial fan. Before the creek channel deepened, the creek would overflow leaving alluvial deposits downstream of point A (Sowers, 2005).
formed levees. As a result of construction of a dam which impounds water and sediment at Searsville Lake, the SFC carries limited material to deposit downstream (point B).
31 Records indicate that a levee passing point C (Figure 9) was a former course of the SFC.
Today, the SFC runs through a channel that was engineering in the 1930s. (Oakland
Museum of California, n.d.)
Although allocations vary by water system (Table 3), the majority of SFC watershed’s residents receive water service supplied by an aqueduct that runs nearly 200 miles from the Hetch Hetchy Reservoir located in Yosemite National Park (California
Water Service, 2016; City of East Palo Alto, 2016; City of Palo Alto Utilities, 2016;
Menlo Park Municipal Water District, 2016; San Francisco Public Utilities Commission,
2016).
Table 3. Allocation disparity in the SFC watershed. Communities of SFC Watershed Served by California Water East Palo Palo Menlo Service Company Alto Alto Park Woodside Portola Valley Population (thousands) 194* 25 67 15 ISG (MGD) 35.68* 1.96 17.08 4.46 Use (MGD) 29.05* 1.57 9.68 2.63 Fixed Charge ($/mo) 20.29** 13.73 16.77 20.08 Variable Rate ($/CCF) 6.73** 3.82 6.73 5.53 Usage (GPCD) 155** 64 153 158 Income ($PCA) 125,559 99,621 18,527 75,257 77,766 * data for Bayshore district and Bear Gulch districts of California Water Service ** data for Bear Gulch district, which serves Woodside and Portola Valley (by author).
32 There are several native species of ecological interest within the SFC watershed, including steelhead trout. The SFC is famous for hosting one of the last remaining wild populations of steelhead trout in the San Francisco Bay.
Similarly, there is a diverse population and robust economy within the watershed boundary; however, intertwined within the excessive affluence of the watershed lies the economically disadvantaged community of East Palo Alto, bringing to mind the inequalities and iniquities of the poor in resource allocation. Forest and low-density residential neighborhoods typify the upper part of this basin, whereas high-density housing and commercial businesses are more common in the lower reaches, as seen in
Figure 10 (Bicknell & Fusco, 2016). Wealth is also concentrated at the higher elevations and all but absent where the creek pours in to the Bay. It should be noted that along with
Stanford University, some of Silicon Valley’s most successful commercial businesses were started in the SFC watershed.
The Joint Powers Authority (JPA) allows the SFC communities to work toward their mutual interests as part of the same organization. The SFCJPA plans, designs, and executes projects that reduce the threat of flood, enhance the ecosystem, augment recreation, and connect communities. Because the SFC watershed is part of the Lower
Peninsula watershed which is part of the Santa Clara Valley, the Santa Clara Valley
Water District (SCVWD) is a member agency of the SFCJPA.
The SFC watershed provides a good case study for critique and validation of the refined watershed sustainability metric owing to the watershed’s water imports, extant
JPA, as well as its socioeconomic diversity.
33 Figure 10. SFC watershed satellite map these are beautiful figures. Contrast between upper watershed which is typified by natural vegetation and limited development while lower watershed has been highly developed (US Geological Society, 2001).
Research Question, Hypotheses and Specific Aims
My primary research question was: How may the WSI be adapted to provide a more useful framework for watersheds in which imports and exports warrant consideration?
My hypotheses were:
• The WSI could be refined and better address watershed sustainability in settings
where imports and exports warrant consideration.
• The SFC watershed would perform poorly in a sustainability analysis, specifically
in one which employs the refined watershed sustainability metric, in hydrological
34 and environmental dimensions, despite the perception that the watershed is
healthy and well-managed.
• Current management efforts do not adequately address the dimensions on which
the watershed sustainability analysis indicates deficiencies.
Specific Aims
To examine these hypotheses and address my research question, I:
1. Applied the WSI to the SFC watershed; identified what limits the WSI from being
applied to watersheds with inter-basin water transfers.
2. Identified and evaluated indicators that reflected and could quantify watershed
sustainability.
3. Used selected indicators to formulate a new model; applied it to the SFC
watershed.
4. Analyzed the results: identified current watershed management practices within
SFC watershed and evaluated their efficacy.
35 Chapter II
Methods
The approach used to investigate the aforementioned inquiries included data collection, calculations, evaluation of indicators, model development, and analysis, as described below.
Application of the WSI to SFC Watershed – Data Acquisition
In order to establish a baseline, I calculated the WSI for the SFC watershed. The metric used three parameters for each of five indicators as previously described in Table
1. Based on the historical record, I was able to determine that my long-term averages would be based upon available data from 1932-1941 and from 1951-2016. I also selected the study period to be 10 years from 2007-2016, based on availability of data. All values were converted into WSI scores according to the methodology described by Chaves and
Alipaz, with exceptions noted (2007).
The four primary indicators measured include: hydrology, environment, life, and policy.
Hydrology
The hydrological indicator is bifurcated into quantitative and qualitative aspects, denoted H1 and H2, respectively.
The quantitative hydrological indicator utilized USGS data in conjunction with historical population estimates and GIS data to calculate the pressure and state
36 parameters. The pressure parameter measures the variation in the basin per capita water availability during the study period, relative to the long-term average, H1:P, and can be expressed as: