Alterations From Small Dams to New Mexico's Rivers and Watersheds
Prepared for CE 598: River Restoration, Spring 2014, by Sara Gerlitz (MWR Candidate)
I forget the names of towns without rivers. A town needs a river to forgive the town. Whatever river, whatever town—it is much the same. The cruel things I did I took to the river. I begged the current: make me better.
-Richard Hugo, “The Towns We Know and Leave Behind, The Rivers We Carry With Us”
ABSTRACT
The prevalence of dams, regardless of size or structural design purpose, serve as indicators of anthropogenic alteration to regional watersheds and are manipulating hydrologic flow regimes worldwide. The total influence of small dams is important to consider when analyzing the larger watershed, even if the catchment is only a few square miles.

The range in types and functions of small dams and impoundments throughout New Mexico is associated with sets of unique and common attributes based around hydrologic alteration. A case study of the Middle Rio Grande presents an example of large-scale hydrologic alteration in terms of tributary influence and sedimentation. Secondly, Starvation Draw, near Deming, NM addresses structural design alterations and breaching issues across a network of small dams within a low-order catchment. These two case studies illustrate how similar analysis techniques can be applied to both large and small systems facing similar issues at different scales.

Regarding ecological alterations, the San Acacia Dam and Bernardo siphon serve as windows into agricultural feedbacks to a losing stream and how habitat structure is altered. Finally, the proposed diversion of the Gila River Allocation will tie into themes of water demand and the delicate water budgets that society has placed on arid New Mexico’s rivers and watersheds and how an ecohydrologic approach should be considered when deciding the fate of the river.


INTRODUCTION

Dams and impoundments have provided for human civilizations for the last several thousand years throughout the globe. The creation of reservoirs for irrigation, reducing flood hazards, enhancing food supply and geographical movement of water across landscapes has been an engineering practice innate to human settlement. However, it’s the scale of these feats that has produced progressive change (Vorosmarty and Sahagian, 2000). A degree of planetary tinkering in the hydrologic cycle has been traced to the creation of impoundments and the resultant trapping of freshwater on the continents through reservoir construction altering water budgets worldwide (Vorosmarty and Sahagian, 2000).

poff?FIGURE.png
FIGURE 1. CONCEPTUAL MODEL—HYDROLOGIC INTERCONNECTIVITY (Poff, et.al, 2006)

The study of small dams and impoundments are important because of the prevalence and magnitude of tributaries and higher order streams in relation to regional watershed analyses. Smaller stream systems and the subsequent disturbances and alterations allow for a land-use signature to be determined on a case-by-case basis. This unique signature allows for a better understanding of hydrologic, geomorphic and ecological linkages (Poff, et. al, 2006). As illustrated in the conceptual model (Figure 1), individual characteristics are not compartmentalized but are instead linked by intrinsic and extrinsic factors. understanding these factors is essential to identifying descriptive relationships on the adjacent reaches, watersheds and even in regards to the global freshwater budget.

A global approach to Poff’s conceptual model is plagued by the severe underestimates in regards to human tinkering of the freshwater budget (Sahagian, 2000). Generally, dam inventories are highly incomplete however the United States has a more reputable estimate due to the presence of dam inventories such as ICOLD and IWPDC which held 68,000 total entries at the beginning of the twenty-first century, including dams as small as 1.83 m (Vorosmarty and Sahagian, 2000). However, others have argued that within major inventory and classification databases, some 2 million small dams are not included. (Poff and Hart, 2002).


poff&hart2002bargraphUSdamsize.png
FIGURE 2. DAM SIZES, BAR CHART, (Poff & Hart, 2002).

This underestimate is illustrated above in Figure 2., which emphasizes the dam height group of small dams (0-2m) in terms of other height classes. Sahaignan found small reservoirs may represent from near zero up to 50% of the total global water impoundment, (Sahaignan, 2000). Of note is the highest accounted for height classes on record are 2-4m and 4-8m respectively. This unaccounted for portion of dams leaves a gap in the databases and ultimately could distort larger scale water budgets. In regards to the management of the multitude of dams, in the U.S. alone, the overarching need to organize and understand fluctuations within freshwater resources is at a potential disadvantage in this regard.

The following discussion of small dams and impoundments discusses the basic components of watershed hydrology in terms of small-scale alterations via the installation and construction of a variety of small dams and impoundments. A focus on the tumultuous state of water in the West will be examined. Specifically, the Rio Grande, Starvation Draw, San Acacia Dam and Gila River catchment areas will be emphasized. These New Mexico case studies will draw on a theme of “alterations” in terms of Poff’s conceptual model. The intrinsic and extrinsic factors or “alterations” to be discussed include anthropogenic, flow regime, hydrologic, design, ecological and future plans for alteration are the topics in which this hydrologic interconnectivity is explored.

ANTHROPOGENIC ALTERATION

The global scale of human alteration to flow regimes and the hydrologic cycle for the planet as a whole has led to the naming of this period of geologic time as the “anthropocene” (Poff, et. al, 2006). Beginning 2000 years ago, the Hopi, Zuni and pueblo peoples of the Southwest began small-scale diversions on regional stream systems. Rivers, such as the Pecos, Little Colorado and Rio Grande saw engineering of small check dams and irrigation canals. (MacDonald, 2010). Flash-forward to present day scenarios in New Mexico and neighboring states such as Arizona, Colorado and Nevada and the magnitude of human settlement and water diversions to storage has exploded. As shown in Figure 3., the last century of water resource development is plotted in terms of reservoir storage volume (Graf, 1999).

grafRESEVOIRstorage.png
FIGURE 3. U.S. RESEVOIR STORAGE INCREASES PER DECADE, (Graf, 1999).

In the Southwest, population increases have created a human demand on water resources that has never been a considerable function of the natural flow regimes for the native streams. For example, the 1960s saw an addition of 18,833 dams in the U.S. It is arguable that the rapid development of water projects and associated infrastructure has spurred the slow race to the finish in regards to relying on the engineering approach to solving water supply issues (MacDonald, 2010).

Another concept to consider regarding anthropogenic alteration is “hydrologic colonialism.” This concept is considered the export of water or water-related services while bearing the environmental costs. This idea is relevant to the cumulative alterations scattered throughout the Western U.S. (Graf, 1999) and particularly in the Southwest where around 80% of all water withdrawals are used for agriculture (MacDonald, 2010). Much of the significance in this, is the relationship between the way dams store water and the economic structure they were built to serve.

A major consequence of anthropogenic alteration is a skew in regional water balances. Oftentimes, there is more storage volume than mean annual runoff in different regions of the U.S. The dates of exceedance (when storage passed runoff) is innately tied to dam and impoundment development time periods. For instance, California storage capacities outpaced runoff in 1927; the Rio Grande in 1935; the Lower Colorado in 1936; Upper Colorado in 1950; Missouri in 1953 and the Texas-Gulf in 1962 (Graf, 1999). For New Mexico, a catalyst to this switch was the development of federal reclamation projects like Elephant Butte Dam and the large-scale hydrologic alteration that has ensued up and downstream on the Rio Grande.


HYDROLOGIC ALTERATION: Middle Rio Grande

The idea of a natural flow regime suggests that magnitude, frequency, duration, timing and rate-of-change in streamflow are key components and the specific ecology is result of these factors (Poff, et. al, 2006). Flow regimes, in terms of the downstream impacts of dams, are correlated with peak discharge and flow duration fluctuations. Peak discharge is the highest amount of flow at a certain point in time and space, while flow duration is the probability a given streamflow was equaled or exceeded over a period of time (nrcs.usda.gov). These capacities, along with a plethora of other physical, chemical and biological characteristics are used to define correlations between dams and hydrologic flow alteration throughout the United States. A conceptual model, Figure 5., can be used to assimilate these different correlations through analyzing difference is the hydrologic retention time (HRT) of a catchment, regardless of size or location (Poff, et. al, 2006).

Dams, as a whole, can be considered as “point” sources of flow and sediment alteration and can be detected through the dramatic changes they create. In contrast, land-use changes like agriculture and urbanization have more turgid or temporally extended flow alterations. Small dams, with their diffuse sub-basins, catchments and minor drainages administer similarly less-detectable changes due to their relative anonymity in larger watersheds (Poff, et. al, 2006).

The cumulative effects of small dams are localized in regards to the flow regime and have significant effects in the immediate spatial context (Graf, 1999). In larger systems fed by smaller sub-basins, “Many stream channels are still adjusting to historical legacies that produce ongoing, lagged geomorphic responses” (274, Poff, et. al, 2006). For example, on the Middle Rio Grande, evaluations in reservoir storage to mean annual runoff ratios estimate existing dams store three to four times the mean annual runoff for the entire system (Graf, 1999). Tributaries and the larger dams for the reach are shown in Figure 4:

MRGmap.jpg
FIGURE 4. MIDDLE RIO GRANDE, (Bovee, et. al, 2008)

Another result of hydrologic alteration is sediment depletion, often found in major watersheds (Poff & Hart, 2002). This hold true for the Middle Rio Grande as historic hydrologic alteration coupled with the accumulations of smaller dams and diversions of the last century has greatly influenced sedimentation conditions. Sediment loads to the Middle Rio Grande from its tributaries (e.g., Chama, Jemez, Galisteo, Rio Puerco, and Rio Salado) were elevated in the late 1800s by arroyo incision and changes in land use in the basin. Major increases in sediment load occurred downstream of the Rio Puerco confluence as a result of channel incision associated with drought and watershed degradation (TetraTech, 2004).

The upper border of the Middle Rio Grande Reach starts directly below Cochiti Dam. From there, the river flows into a relatively broad basin and the valley contains an extensive interconnected network of canals and drains. Around 180 miles of riverside drains and 160 miles of interior drains serve about 128,000 acres of potentially irrigable land in the region. A fair amount of these small dams and diversions are overseen by the Middle Rio Grande Conservation District (MRGCD) between Cochiti Dam and the lower limit of the reach, i.e. at the terminus into Elephant Butte Reservoir (TetraTech, 2004).

The heterogeneity of smaller sub-basins have geospatial and temporal variability making the prediction of water supply difficult (Langbein, et. al, 1951). Small dams are numerous and the aggregate effect is likely to be small except in highly localized contexts, such as in return flows from the network of irrigated lands adjacent to the Middle Rio Grande (Graf, 1999). Small structures on tributaries, such as the Jemez, Rio Puerco and others, affect the hydrologic behavior and exert local influences on riparian environments. Ultimately, by changing the flow regimes of tributaries, the “natural flow regime” of a larger system is subject to cumulative hydrologic alteration.

poff&hartflowchart2002.png
FIGURE 5. HYDRAULIC RESIDENCE TIME CONCEPTUAL MODEL (Poff & Hart, 2002)


DESIGN ALTERATION: Starvation Draw

In New Mexico, some of the older earthen dams, which were built in the 1930-1960s are reaching their life expectancy (Bush, 1997). Originally, some of these earthen dams were designed for habitat restoration. Specifically, the control of sediment transport was the impetus however the structures have in-turn become sediment-sinks. Sediment accumulation has reduced the hydraulic storage capacity of the dams increasing the chance for a breach (Bush, 1997). A dam breach has the potential to cause great erosion and damage downstream. In a study directed by the Bureau of Land Management, four earthen detention dams on Starvation Draw, near Deming, New Mexico, were evaluated for the risk of overtopping. Reports concluded that accumulative loss of sediment over the past sixty years was potentially high (HydroTech).

In order to determine the state of the small dams, the hydraulic flow for the watershed was examined with and without the five dams. This 17square mile watershed was broken into several sub-basins for modeling hydraulic flow through the dam structures.


mapstarvationdraw.jpg
FIGURE 6. STARVATION DRAW WATERSHED, (HydroTech).

Originally built to deter erosion in the 1950’s, the dams have become overgrown with deep rooted vegetation and show evidence of surface erosion (Figure 7.). An existing spillway structure design at Starvation Draw Dam #5, located last in line on a five-dam impoundment network within the draw, was found to be at risk to design failure. An extensive report on design options concluded that in order to avoid dam collapse a new spillway structure is needed (HydroTech).


SDupstream.jpgSDdownstream.jpg
FIGURE 7. STARVATION DRAW: UPSTREAM/DOWNSTREAM IMAGES (Bush, 1997).

For the past 60 yrs, the dam was subjected to overflowing and an array of loose sediments accumulated behind the structure. As shown in Figure 8., the storage to head relationship for the dam was observed in terms of the original design storage volume to more recent storage volume capacities after the sediment accumulations. Other design issues for all five dams include the state of trash racks, or screens, which collect large amounts of debris during storm events and require occasional clearing. The earthen dams stop soil from continuing downstream and the flow is channelized at the dam outlet (Bush, 1997).

damstorageSD.jpg
FIGURE 8. STARVATION DRAW, DAM #5 SEDIMENT RETENTION, (HydroTech).

Additional design issues found at the study site were the unkempt installation of silt fences for erosion control and their failure to reduce erosion. The risk assessments and state of structural functions and erosion controls in Starvation Draw illustrate the continued maintenance needs in addition to reconstruction and replacement of aging structures throughout the West (Bush, 1997).

Small structures, of a similar design period as the Starvation Draw dams, make-up part of a regional network of rangeland management techniques in the Southwest. Through the installations of stock-watering ponds, cattle grazing needs were aided across federal rangelands. Traditional cattle grazing requires a large number of water supplies only short-distances apart. For this reason many thousands of small reservoirs have been built (in some cases as many as one-per-square mile) throughout the federal lands of the West.The individual stock-watering pond represents a small investment but the aggregate of all ponds was an investment of many millions of dollars during the 1950s (Langbien, et. al, 1951). The maintenance needs of these small impoundments, like the risks found in Starvation Draw, are of an order of magnitude hard to calculate let along address within a reasonable timeframe.

In lieu of these regional scale needs, removal of small dams has become increasingly prevalent in the U.S. due to several factors including safety and repair costs for aging infrastructure. For example, many small dams in the East and Midwest that were built in the mid-1800s to early 1900s have antiquated uses such as milling and the impetus for repairing and maintaining them is an economic more so than an environmental decision. (Shafroth, et. al, 2002).

An Arizona stock pond study from the 1950’s conducted by the Department of the Interior on federal rangelands offers insights into the function and design variations of small dams and infrastructure (Langbein, et. al, 1951). Besides the significant economic influence brought forth from stock pond networks throughout the West on the cattle industry, it’s the sum effect that is important to consider. A high density of these impoundments on small basins, such as Starvation Wash, is of interest when examining a watershed as a whole whether the total influence is substantial or not depends on each unique basin.

ECOLOGICAL ALTERATION: San Acacia Dam & Bernardo Siphon

Throughout the breadth of his work, Poff has proposed that damming and land use changes induce complex fluvial processes on the water and sediment regimes associated with the native hydrograph. (Poff, et. al, 2006). The affect on aquatic ecosystem structure and function throughout the U.S. is profound in regards to anthropogenic disruption however natural disturbances are often ingrained within various watersheds and across different magnitudes.

The ecological effects of small dams are arguably similar to natural disturbances, or barriers such as waterfalls, debris dams and beaver dams. These ecosystem attributes and the similarities to small dams and impoundments are described in Figure 9. (Hart, et. al, 2002). For example, large changes in aquatic habitat, sediment transport and biogeochemical cycles are attributed to beaver dams however the impact to natural flow regimes is negligible. Although relatively benign to riverine biological processes, waterfalls act as natural barriers to upstream reaches. Hart discusses these hypothetical relationships in terms of anthropogenic infrastructure types and sizes. The majority of streams in New Mexico flow through, discharge to, or receive inflows from built “barriers".

hartAnalogEcochart2002.png
FIGURE 9. HYPOTHETICAL RELATIONSHIPS OF ECOSYSTEM BARRIERS (Hart, et. al, 2002).


One in particular that influences the aquatic ecosystem in terms of anthropogenic tinkering is found within the central region of the state at San Acacia Dam.

Most impoundment structures found in the U.S. West are for agricultural use. A prime example of this sort of small dam can be found in the San Acacia Reach of the Middle Rio Grande. The San Acacia Dam is a low-head diversion structure located on the Rio Grande approximately 19 km (12 mi) upstream from the city of Socorro, NM. The diversion was constructed by the Middle Rio Grande Conservancy District (MRGCD) in 1934 and rehabilitated by the Bureau of Reclamation (BOR) in 1957 to deliver water for irrigation to farms in the Socorro area. As a result of the diversion, the streamflow downstream from San Acacia Dam can be greatly diminished during the irrigation season (March 1–October 31). This reach of the Middle Rio Grande has regularly relied on irrigation return flows, from the upstream Lower San Juan Riverside Drain, which are occasionally a major source of streamflow within the Rio Grande (Figure 10.). For example, in 2002 and 2003, the drain contributed over one-half the late summer flow in the Rio Grande (Bovee, et. al, 2004).


RioGrandeGAINSLosses.jpg
FIGURE 10. SAN ACACIA REACH, AVERAGE DAILY GAINS/LOSSES, 1999-2004, (Bovee, et. al, 2008).

These current flow regimes are a driving force in regards to the ecological state of the river. San Acacia Dam is located in a reach of the Rio Grande that has been designated as critical habitat for two endangered species, the Rio Grande Silvery Minnow and Southwest Willow Flycatcher. The critical habitat designation in the Rio Grande for the minnow, H. amarus extends from Cochiti Dam to Socorro County, NM. The flycatcher Empidonax traillii extimus, has a larger and more sporadic geographical range (U.S. Fish and Wildlife Service, 2003). The two main issues relating San Acacia Dam to the well-being of these listed species include potential habitat losses and habitat fragmentation (Bovee, et. al, 2004).

A proposed diversion that could reduce flow in the reach is the Bernardo siphon. This project would move return flows, most of which had been previously diverted at Isleta Dam, from the east side of the river to the west side for reuse. By design, as illustrated in Figure 11., the siphon would intercept up to approximately 150 ft3/s of flow and transport it under the river into Drain Unit 7 on the west side. By redirecting flow from the Belen division from the Lower San Juan drain to the siphon, diversions at the San Acacia headworks could be reduced or eliminated. Since components of the silvery minnow habitat are influenced by hydrologic conditions, the relationship of hydrology to habitat for these species is crucial. Changes, such as the Bernardo siphon, in the amount of water needed to maintain restored areas or to achieve mandated target flows have important societal, economic, and ecological consequences. (Bovee, et. al 2004).

sanacacia.jpg
FIGURE 11. SAN ACACIA DIVERSION DAM, IRRIGATION DIVERSIONS, (Bovee, et. al, 2008).

FUTURE ALTERATION: Gila River Allocation Proposals

Spurring from nearly a decade of water allocations on the Colorado River, the Arizona Water Settlement Act (AWSA) of 2004 is the latest piece of the puzzle fit towards a contentious and finite resource. What has been decided by the federal courts and congressional compact processes is an allocation along the Gila River in an amount of 14,000 acre-feet to the benefit of the people of New Mexico with up to $128 million in non-reimbursable federal funding available (http://nmawsa.org).

Stipulations include the use of funds in southwestern New Mexico only for application within Grant, Luna, Hidalgo and Catron counties (http://nmawsa.org). Leasing or marketing of the water is not allowed under the act which specifically designates the water to be consumed in New Mexico (http://nmawsa.org). The question at hand is, which of the sixteen projects currently submitted will the deciding agency, the New Mexico Interstate Stream Commission, chose to implement?

The bedrock foundation (which will ultimately control this decision) is the traditional prior appropriation doctrine of “use it or lose it”, the prevailing theory distributing water allocations within New Mexico (Brookshire, Gupta & Matthews). In the Gila River, which is part of the Lower Colorado River Watershed, the dominant water applications (Figure 12.) reflect the traditional beneficial use of water towards irrigated agriculture, mining, municipal/domestic supply, commercial/industrial and livestock (Brookshire, Gupta & Matthews). These uses are dependent upon the hydrological links between both surface and groundwater within the basin. Subsequent patterns of development of water resources has led to the current state of New Mexican watersheds as discussed in this paper.

biofinal.jpg
FIGURE 12. LOWER COLORADO RIVER WATERSHED, WITHDRAWALS IN GILA RIVER WATERSHED, TOTAL AMOUNT BY CATEGORY, (Brookshire, et. al, 2012).

These “significant changes in the water and sediment regimes induced by the extensive and intensive changes in land use and by damming have induced complex changes in fluvial processes and in aquatic ecosystem structure and function across the U.S.”, (269, Poff, et. al, 2006). In this regard, the application of an environmental methodology could break the pattern of hydrologic alterations from small dams and impoundments. Additionally, through the use of an ecohydrology approach to making this important decision, a new lens on the conjunctive management of surface and groundwater resources as well as in defining “beneficial use” of water within the State of New Mexico may be feasible.

Ecohydrology is considered as an interdisciplinary approach across several fields, which acknowledges that vegetation, water and nutrients are intimately coupled (Newman, et. al., 2006). In sum, ecohydrology recognizes “changes in one bring about changes in others” in regards to the entire ecosystem (Newman, et. al., 2006). At present, some of the proposed projects for the Gila River water allocation are trending towards this approach. Currently submitted projects range widely from reservoir construction within tributary arroyos to municipal infrastructure improvements, with a handful of ecological studies proposed (http://nmawsa.org). Ecohydrology promotes understanding between hydrological, biogeochemical, and ecological processes through place- based science. It is arguable that the AWSA has an opportunity to do just this with the federally allocated funds (Brookshire, Gupta & Matthews).

Despite the upcoming deadline, (December, 2014), on which the ISC must decide how to use the water, a few factors should be considered. First, several new studies suggest that a combination of aggressive conservation, acquisition of existing water rights and development of groundwater resources outside the Gila Basin may be sufficient for projected water needs of the region well into the future. Economic analyses indicate that these measures are less expensive than construction and development of a dam and diversion infrastructure. The ecohydrology route could be directly applied to proposals that encompass specific projects focused on conservation, alternative water supply development, recharge, education and watershed management (Brookshire, Gupta & Matthews).

While attempting to decide which option to take the ISC has a rare opportunity to directly apply the emerging field of ecohydrology. Regardless, “an ecosystem approach should still be done and is critical for adaptive management of the riparian systems undergoing other potential stresses, such as drought and climate change,” (Brookshire, Gupta & Matthews, pg. 242).

CONCLUSIONS:

New Mexico, the high-desert, arid land with a populous surviving on the “ribbon of green” remnants of once wild rivers demonstrates a plethora of environmental issues. The case studies and main issues discussed summarized different states, challenges and potentials for New Mexico’s small dam infrastructure. Commonality found between the four regions is rooted within the fundamental responses of humans to living in lands where water is scare: move the water to where it’s most needed.

In this regard, the relocation, or reallocation in some regards of natural flow regimes of the Rio Grande, the Gila River and in an infinitesimal desert draw is a uniting theme. Secondary to this is the cumulative impacts found throughout each region. For the Middle Rio Grande the influence of tributary systems and the associated alterations from this complex network of infrastructure covers the breadth of water resource issues within the United States. In common to addressing the proliferation of small dams and impoundments throughout the nation is the issue of infrastructure maintenance, upkeep and risks of failure. Starvation Draw highlighted this in a small catchment context with also relays back to the cumulative concept of how our restoration attempts on a dynamic desert landscape can warrant criticism and even propose removal.

Stressing these findings even further are issues of endangered species and agricultural withdraw along the San Acacia Reach of the Rio Grande. The San Acacia Dam and Bernardo siphon project connected two anthropogenic alterations within a singular location. This multitude of overlapping reactions, responses and consequences of small dam alterations on the environment precluded the discussion of the Gila River Allocation. The last case study of the Gila presented ideas of institutional and management structure to the range of issues examined. Ultimately, it is the opinion of this author as well professionals within the natural resource field like Elinor Ostrom and Simon Levin that “ecosystems are complex, adaptive systems and hence, are characterized by historical dependency, complex dynamics, and multiple basins of attraction. The management of such systems presents fundamental challenges, made especially difficult by the fact that the putative controllers (humans) are essential parts of the system and, hence, essential parts of the problem,” (139, Ostrom, 2010).

REFERENCES:

Arizona Water Settlement Act (AWSA) of 2004, (2013). http://nmawsa.org/

Bovee, K.D., Waddle, T.J., & Spears, J.M. (2008). Streamflow and Endangered Species Habitat in the Lower Isleta Reach of the Middle Rio Grande. Open File Report 2008-1323,U.S. Geologic Survey, U.S. Department of the Interior.

Brookshire, D.S., Gupta, H.V. and O.P. Matthews, (2012). Water Policy in New Mexico: Addressing the challenges of an uncertain future. RFF Press, New York, NY.

Bush, Jessica, (1997). Hydrology Analysis of Starvation Draw: Evaluation of Starvation Draw Dams for Sediment Control and Restoration of Upstream Habitat. Report, Master of Civil Engineering degree requirement, NMSU.

Graf, W. L. (1999). Dam nation: A geographic census of American dams and their large-scale hydrologic impacts. Water Resources Research, 35(4), 1305–1311.

Hart, David D., et. al,(2002). Dam Removal: Challenges and Opportunities for Ecological Research and River Restoration. Bioscience, 52(8), 669-681.

HydroTech Engineering, (date unknown). Starvation Draw Dam Final Version. Attained from email correspondence with Jessica Bush, Socorro Division, Bureau of Land Management, March, 2014.

Langbein, W.B., Hains, C.H. and Culler, R.C. (1951). Progress Report: Hydrology of Stock-Water Reservoirs in Arizona. Geological Survey Circular 110, United States Department of the Interior.

MacDonald, G. M. (2010). Water, climate change, and sustainability in the southwest. Proceedings of the National Academy of Sciences of the United States of America, 107(50), 21256–21262. doi:10.1073/pnas.0909651107

Natural Resources Conservation Service, USDA, (2010). Federal Stream Corrodior Restoration Handbook, Chapter 2: Stream Corridor Processes and Characteristics, www.nrcs.usda.gov.

Newman, B.D., et. al., (2006). Ecohydrology of water-limited environments: A scientific vision. Water Resources Research, (42).

Poff, N.Leroy, Hart, David D., (2002). How dams vary and why it matters for the emerging science of dam removal, Bioscience, 52(8), 659-668.

Poff, N. L., Bledsoe, B. P., & Cuhaciyan, C. O. (2006). Hydrologic variation with land use across the contiguous United States: Geomorphic and ecological consequences for stream ecosystems. Geomorphology, 79(3-4), 264–285.

Price, J., Lewis, B., & Rutherfurd, I. (2003). Water Quality in Small Farm Dams. 28th International Hydrology and Water Resources Symposium: About Water; Symposium Proceedings, 3.

Rinne, John N. (2004). Flow, Fish, Foreigners and Fires: Relative Impacts on Southwestern Native Fishes.

Sahagian, D. (2000). Global physical effects of anthropogenic hydrological alterations: sea level and water redistribution. Global and Planetary Change, 25(1–2), 39–48.

Shafroth, Patrick, B., et. al., (2002). Potential responses of riparian vegetation to dam removal. Bioscience, 52(8), 703-712.

Tetra Tech EM Inc., (2004). Habitat Restoration Plan for the Middle Rio Grande, Middle Rio Grande Endangered Species Act Collaboration Program, Habitat Restoration Subcommittee.

Vörösmarty, C. J., & Sahagian, D. (2000). Anthropogenic Disturbance of the Terrestrial Water Cycle. BioScience, 50(9), 753–765.