Forthcoming in Environment and History ©2019 …Forthcoming in Environment and History ©2019 The White Horse Press of Reclamation’s irrigation and multipurpose dams allowed the

Forthcoming in Environment and History ©2019 The White Horse Press

www.whpress.co.uk ‘Thirsty Sugar Lands’: Environmental Impacts of Dams and Empire in Puerto Rico since 1898 Matthew P. Johnson Abstract

The story of North American dam building is incomplete without the United States’ Caribbean territories because the motivations and consequences of building dams there were different than on the mainland. Between 1910 and 1914, the Puerto Rican Irrigation Service built three large dams in the island’s south-east to irrigate canefields owned by North American sugar companies. The water harnessed by the South Coast Irrigation Project (SCIP) doubled sugar yields in its district in the decades following the project’s completion, generating huge profits for North American sugar interests. However, the sugar boom did not lead to sustained economic growth on the island and did little to increase the standard of living for many Puerto Rican fieldworkers and their families.

The project also brought a bumper crop of unforeseen environmental consequences. North American engineers underestimated the vagaries of Puerto Rico’s climate. Droughts and extended dry periods led to water shortages that continually menaced irrigation. Stormy weather created another unanticipated problem for the dams. Hurricanes and heavy rains in the mountains north of the sugar lands contributed to high erosion rates that accelerated sediment accumulation in the reservoirs and reduced their storage capacity. Together, drought and siltation threatened to render the dams obsolete. Hydroelectric turbines, installed as an afterthought, provided affordable electricity that powered groundwater pumps to make up for surface water shortages. Groundwater saved the sugar boom, but sediments continued to build in reservoirs, an enduring legacy of US imperialism that is expensive to mitigate. The SCIP preserved socioeconomic and racial inequalities, but reengineered the island’s hydrosphere, turning the parched south-east into a giant canefield and its rivers into repositories for sediments. Introduction

In 1907, drought devastated economic life in southeastern Puerto Rico. The island’s

southern coastal plains had fertile soils and rich pastures that supported a profitable cattle

ranching industry. But water shortages were a constant threat. Mountains to the north

diverted much of the island’s rainfall, and extended dry periods were frequent on the south

coast. That year’s drought was especially grave. Governor Regis Henri Post complained that

‘the drought was so severe on the south side of the island during last winter that a great

number of cattle died for want of pasture, so that instead of exporting we were obliged to

import cattle for our food supply, and the price of beef in country towns has risen to almost


www.whpress.co.uk prohibitive figures.’1 The dreadful dry winter weather had persisted into the spring and

summer months, and the US Department of Agriculture’s Weather Bureau commented that a

drought of such pronounced character was unprecedented in their records.2

Cattle ranchers were not alone in their suffering. North American and Puerto Rican

azucareros3 that had been trying to turn the southern alluvial plain’s rich pastures into

canefields also struggled with the drought. The United States took possession of Puerto Rico

from Spain in the aftermath of the 1898 Spanish-American War, and in 1901, eliminated the

tariff barrier on Puerto Rican sugar. Climbing prices on the world market encouraged south-

eastern azucareros to put much of the land formerly used as pasture under cultivation.

Reflecting on the spread of canefields, Governor Post wrote ‘In 1906 the largest output in the

history of the island was the result of this expansion, and it was fully expected that this year’s

yield would exceed that of the previous year.’ But water shortages had hampered their

efforts. Post continued, ‘On the south and east sides of the island there was practically no rain

for ten months of the year, so that much of the cane planted on land without irrigation was a

total loss.’4 As these fledgling cane cultivators watched their stalks wither, they searched for

and came up with a solution: irrigation.

Small irrigation works had been in place since the Spanish, but they were not large

enough to match the needs of the growing azucarero interests. Drought underscored the

potential benefits of reengineering Puerto Rico’s rivers on a larger scale. As the dry weather

persisted, azucareros and government officials saw irrigation as the salvation of Puerto Rico’s

canefields.

1 Annual Report of the Governor of Porto Rico, 1907, 21, Archivo General de Puerto Rico (hereafter AGPR), San Juan, Annual Reports. The Annual Reports of the Governor of Puerto Rico are also available online through ProQuest Congressional. 2 Willis L. Moore, Report for December 1907 Porto Rico Section of the Climatological Service of the Weather Bureau, (Richmond, VA: Weather Bureau, 1907). 3 The term azucarero is used in this article to refer to cane planters, mill owners, managers and others whose financial interests were wedded to sugar cultivation. 4 Annual Report of the Governor of Porto Rico, 1907, 17, AGPR, Annual Reports.


www.whpress.co.uk Between 1910 and 1914 the Puerto Rican Irrigation Service built the first three large

dams in Puerto Rico to irrigate sugarcane in the south-east. These three dams, Guayabal,

Carite, and Patillas, along with two smaller ones, Coamo and Melania, formed the South

Coast Irrigation Project (SCIP), which doubled sugar production in the decades following the

project’s completion in 1914.5 Sugar production boomed and generated tidy profits for sugar

companies. Although the irrigation system facilitated a huge expansion in cane production, it

reinforced class and racial inequalities, and recurrent drought and rapid sedimentation

jeopardized the project’s long-term success.

The SCIP strengthened socioeconomic inequalities in the southeast. Sharp social

inequalities had beset Puerto Rico’s sugar lands long before the SCIP’s irrigation water

flowed, and the project did not create disparities in land distribution and wages in the

southeast.6 Yet, the irrigation dams strengthened these inequalities by designating a quarter of

the island’s best soils to sugarcane production and encouraging Puerto Ricans to sell their

land to US sugarcane corporations. The irrigation system made changes in land use and land

ownership difficult because the Irrigation Service imposed a tax on landowners in the district

that raised rent and made intensive cane cultivation necessary for land to remain profitable.

For those laboring in canefields and mills, low wages made it nearly impossible to afford

land in the district.

The SCIP also brought a bumper crop of unforeseen consequences. The project’s

reservoirs were the first large irrigation dams in the Caribbean built by US engineers, who

were inexperienced at building dams in the tropics and underestimated the vagaries of Puerto

5 The scheme also included plans for third small dam, Toro Negro, in mountains above Lago Guayabal. The Irrigation Service never built a storage reservoir there, but did dig a diversion tunnel through the mountains to channel water from the Toro Negro river into the Jacaguas river and Lago Guayabal. In April 1929, the Irrigation Service finished construction on a hydropower station at Toro Negro. See: Annual Report of the Governor of Porto Rico, 1913, 54, 279-282, and Annual Report of the Governor of Porto Rico, 1929, 61, AGPR, Annual Reports. 6 Concentration of land ownership was a legacy of Spanish rule. See: César J. Ayala and Laird W. Bergad, ‘Rural Puerto Rico in the Early Twentieth Century Reconsidered: Land and Society, 1899-1915,’ Latin American Research Review 37 (2) 2002: 65-97.


www.whpress.co.uk Rico’s climate.7 Droughts and extended dry periods led to water shortages that continually

menaced irrigation. Stormy weather created another unanticipated problem for the dams.

Hurricanes and heavy rains in the mountains north of the sugar lands contributed to high

erosion rates that accelerated sediment accumulation in the reservoirs and reduced their

storage capacity. Together, drought and siltation threatened to render the dams obsolete.

However, one unintended consequence proved to be advantageous for azucareros.

Hydroelectric turbines, installed as an afterthought to the irrigation system, proved to be

fundamental to the project’s success. Affordable electricity from the Carite Dam powered

groundwater pumps that provided essential irrigation water to make up for dramatic surface

water shortages. Had it not been for hydroelectricity and groundwater pumps, the dams might

not have supplied sufficient water for such a dramatic growth in sugar production.

Groundwater may have saved the sugar boom, but rapid siltation continued to shrink the

storage capacity of the south-east’s reservoirs. The SCIP preserved socioeconomic

inequalities but reengineered the island’s hydrosphere, turning the parched south-east into a

giant canefield and its rivers into repositories for sediments.

Historians, Sugar, and Dams

The scholarship on dams and imperialism centers on the continental United States.

Donald Worster famously used the language of imperialism to discuss dam building and

economic growth in the American West. Worster’s discussion built on the work of historians

who had referred to the south and west as colonies subservient to the industrial north-east.

Using the same language, but challenging their conclusions, Worster argued that the Bureau

7 They might be the tropical world’s first large (greater than 15 meters in height), reinforced-concrete irrigation dams built with US engineering expertise. Some other projects to consider when determining the unprecedented nature of the SCIP are: Jamaica’s Rio Cobre Dam (1872), a small diversion dam built for irrigation; Puerto Rico’s Comerío Dam (1907), a small diversion dam built for municipal hydroelectric power; the Philippines’ Wawa Dam (1909), a large dam built to supply water to Manila; the Philippines’ Buhisan Dam (1912), a small dam built to supply water to Cebu; and Panama’s Gatun Dam (1913), a large dam built to retain water for the Panama Canal.


www.whpress.co.uk of Reclamation’s irrigation and multipurpose dams allowed the west to overcome its colonial

status and become an empire itself after 1945.8 Worster’s discussion neglected the United

States’ formal overseas empire, where a dam-building boom had unfolded under very

different ecological, political, and socioeconomic circumstances.

If hydraulic engineering liberated the American West from its informal colonial

status, dams further entrenched colonialism in the United States’ overseas territories. Puerto

Rico’s first large dams were not intended to be democratizing. In the American West, dam

advocates had advertised irrigation as a means of opening land to small farmers, and many

believed that this newly irrigated land would make society more egalitarian. It was mostly in

hindsight that scholars publicized the shortcomings of these large dams, highlighting that

they had in fact sharpened social inequalities.9

The terms were different in Puerto Rico. The government erected dams in the south-

east with the explicit purpose of watering large sugarcane plantations, which were export-

oriented and mostly owned by large, vertically-integrated US corporations. Puerto Rico’s first

large dams entailed entirely different socioeconomic goals than those on the mainland: they

were designed to profit from existing socioeconomic hierarchies, not change them.

Racism has been an enduring characteristic of US imperialism in the Caribbean that

influenced how the costs and benefits of economic growth were distributed. The SCIP was

unexceptional in this regard: the owners and managers of the large North American sugar

companies that profited from irrigation water were mostly white, whereas the Puerto Ricans

that labored in the cane fields were mostly of Spanish or African decent, or mixed-race.10 As

8 Donald Worster, Rivers of Empire: Water, Aridity, and the Growth of the American West (New York: Oxford University Press, 1985). 9 Marc Reisner, Cadillac Desert: The American West and its Disappearing Water (New York: Penguin, 1986). For more on the environmental consequences of large dams in the American West, see: Richard White, The Organic Machine (New York: Hill and Wang, 1995); Philip Fradkin, A River No More: The Colorado and the West (Berkeley: University of California Press, 1996); Mark Fiege, Irrigated Eden: The Making of an Agricultural Landscape in the American West (Seattle: University of Washington Press, 1999); April R. Summitt, Contested Waters: An Environmental History of the Colorado River (Boulder: University of Colorado Press, 2013). 10 For race and empire in the US Caribbean, see: Ellen Suarez Findley, Imposing Decency: The Politics of Sexuality and Race in Puerto Rico, 1870-1920 (Durham: Duke University Press, 2000); Laura Briggs,


www.whpress.co.uk with the SCIP’s socioeconomic goals, these irrigation dams were designed to profit from

existing racial hierarchies, not change them.

The environmental footprint of irrigation dams was also different in Puerto Rico than

on the mainland. In Puerto Rico, US engineers had to contend with an unfamiliar tropical

climate—rainfall in particular—that presented new challenges. Furthermore, the island’s

colonial status perhaps disincentivized long-term thinking, if not among engineers

themselves, then at least among the colonial government that planned and funded the dams.

Both variables encouraged engineers to neglect sedimentation, a problem that was not

discussed in any of the project’s surveys or plans, but which came to have devastating long-

term consequences for the island’s inhabitants.

Environmental historians have discussed an array of environmental problems

associated with dam-building in the mainland United States, but not sedimentation.11 Within

the United States and its territories, rapid siltation is a problem unique to the Caribbean,

where the combination of powerful storms, steep mountains, and loose soils leads to

accelerated sediment accumulation in reservoirs. Between 1914 and 1934, Lago Guayabal

silted at a rate of roughly 2.3 percent per year, whereas the average large dam on the

mainland fills with sediment at a rate of roughly 0.2 percent per year.12 Though North

American sugar companies and consumers were the primary beneficiaries of the profits and

sucrose extracted from Puerto Rico’s canefields, neither had to deal directly with the long- Reproducing Empire: Race, Sex, Science, and U.S. Imperialism in Puerto Rico (Berkeley: University of California Press, 2003). For race and US imperialism broadly see: Eric T. Love, Race over Empire: Racism and U.S. Imperialism, 1865-1900 (Chapel Hill: University of North Carolina Press, 2004); Kristin L. Hoganson, American Empire at the Turn of the Twentieth Century (New York City: Bedford, 2016). 11 Geographers and engineers have written more, albeit not much, about sediment accumulation behind US dams. See: William Graf, et al., ‘Sedimentation and Sustainability of Western American Reservoirs,’ Water Resources Journal 46 (2010). 12 Patrick McCully, Silenced Rivers: The Ecology and Politics of Large Dams (New York: Zed Books, 2001), p. 107. Lago Guayabal’s siltation rate was calculated from data found in the Annual Report of the Utilization of Water Resources and Puerto Rico Irrigation Service (South Coast), Fiscal Year 1937, 6-7, National Archives, College Park, MD (hereafter NARA II), Record Group (hereafter RG) 126, Office of the Territories, Series: Classified Files, 1907-1951 (hereafter CF), Box 1001. Lago Guayabal filled with sediment at the exact same rate as the average dam in China, the region with the highest average siltation rates in the world. See: Alessandro Palmieri et al., Reservoir Conservation Volume 1: Economic and Engineering Evaluation of Alternative Strategies for Managing Sedimentation in Storage Reservoirs (Washington D.C.: World Bank, 2003), p. 1.


www.whpress.co.uk term consequences of sedimentation, which continues to plague the south coast’s reservoirs

and diminish their storage capacity.

This paper also adds to debates about US dam-building overseas. Historians have

increasingly seen economic and political goals tied to informal empire as the impetus for US

financial and technical support in dam-building projects overseas. However, this scholarship

has yet to escape the Cold War.13 US engineering influence overseas before the 1940s and in

areas not essential to Cold War geopolitics, such as Puerto Rico, remain understudied.14

While Cold War imperatives and development provided strong motivation to build

large dams overseas in the latter half of the twentieth century, shoring up sucrose supplies for

consumers and profits for American corporations and was a strong incentive in the first half.

The SCIP was built outside the continental US, but with considerable US financial and

technical assistance, and decades before the big dam-building projects of the 1930s or the

onset of the Cold War. The SCIP was not a precedent to those development projects designed

to help bolster the United States’ informal empire in the latter half of the century. It was built

to help North American corporations extract greater wealth from Puerto Rico’s soils. In this it

largely succeeded, although in the process it also unleashed enduring environmental changes.

Such changes have thus far been unstudied by Caribbean environmental historians.

Existing work on the sugar industry has focused on deforestation and overlooked the changes

that canefields engendered in the region’s hydrosphere.15

13 Richard P. Tucker, ‘Containing Communism by Impounding Rivers: American Strategic Interests and the Global Spread of High Dams in the Early Cold War,’ in J.R. McNeill and Corinna R. Unger (eds.) Environmental Histories of the Cold War, pp. 139-164 (New York: Cambridge University Press, 2010); Nick Cullather, The Hungry World: America’s Cold War Battle Against Poverty in Asia (Cambridge: Harvard University Press, 2010), pp. 108-134; Christopher Sneddon, Concrete Revolution: Large Dams, Cold War Geopolitics, and the US Bureau of Reclamation (Chicago: University of Chicago Press, 2015). 14One exception is David Ekbladh, who discusses a development mission that preceded the Cold War as a major stimulus for overseas engineering projects. However, his discussion of formal US imperialism focuses on non-dam related development projects in the Philippines. See: David Ekbladh, Great American Mission: Modernization and the Construction of an American World Order (Princeton: Princeton University Press, 2009). 15 Richard Tucker, Insatiable Appetite: The United States and the Ecological Destruction of the Tropical World (Berkeley: University of California Press, 2000); Reinaldo Funes Monzote, From Rainforest to Cane Field in Cuba: An Environmental History since 1492 (Chapel Hill: University of North Carolina Press, 2008); ‘The Greater


www.whpress.co.uk Puerto Rico is a fitting setting to further explore the ecological legacies of sugar. The

island’s sugar industry has inspired a wealth of scholarship focused on Puerto Rico’s

economic and political history.16 Likewise, the sugar boom has prompted rich social histories.

Notably, anthropologists Julian Steward and Sidney Mintz conducted fieldwork in the south-

eastern sugar lands, which highlighted the economic and political impact of US occupation

and the inclusion of Puerto Rican sugar behind US tariff walls. 17 These authors also

discussed the economic dependence and social inequalities that accompanied the sugar boom.

However, no historians have probed the ecological dimensions of Puerto Rico’s sugar

industry at any length.18

The environment shaped the early twentieth-century Puerto Rican sugar boom. The

rich soils of the alluvial plain were suited for cane production. Although the climate in the

south-east was too dry for intensive cane farming, small rivers running from nearby

mountains could be dammed to divert water and produce electricity to power groundwater

pumps. The irrigated sugar boom in the south-east also came with a host of unintended

ecological consequences. Most prominently irrigation reservoirs became the repositories for

sediments, shortening their lifespan.

Caribbean and Transformation of Tropicality,’ in John Soluri, Claudia Leal, and José Augusto Pádua (eds.) A Living Past: Environmental Histories of Modern Latin America, pp. 45-67 (New York: Berghahn Books, 2018). 16 Laird W. Bergad, ‘Agrarian History of Puerto Rico, 1870-1930,’ Latin American Research Review, 13: 3 (1978): 63-94; James L. Dietz, Economic History of Puerto Rico: Institutional Change and Capitalist Development (Princeton, NJ: Princeton University Press, 1986); Rafael Bernabe, ‘Prehistory of the Partido Popular Democrático: Muñoz Marín, the Partido Liberal, and the Crisis of Sugar in Puerto Rico, 1930-35,’ PhD diss., State University of New York, 1989; Francisco Scarano, Puerto Rico: cinco siglos de historia (San Juan, PR: McGraw Hill, 1993); César J. Ayala, American Sugar Kingdom: The Plantation Economy of the Spanish Caribbean, 1898-1934 (Chapel Hill, NC: University of North Carolina Press, 1999); Ayala and Bergad, ‘Rural Puerto Rico in the Early Twentieth Century Reconsidered: Land and Society, 1899-1915,’ 2002; César J. Ayala and Rafael Bernabe, Puerto Rico in the American Century: A History since 1898 (Chapel Hill, NC: University of North Carolina Press, 2007); Ruben Nazario, El paisaje y el poder: la tierra en el tiempo de Luis Muñoz Marín (San Juan: Ediciones Callejon, 2014). 17 Julian H. Steward (ed.), The People of Puerto Rico, (Urbana, IL: University of Illinois Press, 1956); Sidney Mintz, Worker in the Cane: A Puerto Rican Life History, (New Haven, CT: Yale University Press, 1960). 18 César Ayala briefly noted the connection between the irrigation project and malaria, but did not discuss this relationship at length. See: Ayala, American Sugar Kingdom, p. 182.


www.whpress.co.uk This paper parallels the work of Stuart Schwartz, who discussed the impact that the

environment (namely storms) had on the development of Puerto Rican politics.19 This

relationship was dialectical and Puerto Rican politics, influenced by US imperialism after

1898, transformed the island’s environment, reshaping the impact that severe weather had on

Puerto Rico. Schwartz considers the damage that hurricanes wrought on the island, but he

does not make the connection between storms and their consequences for the island’s

reengineered hydrosphere, where reservoirs collected sediments that heavy rains washed into

rivers.20

Irrigation Dams and Water Shortages

Puerto Rico is a mountainous island. The Cordillera Central, the island’s principal

mountain range, runs east to west and constitutes about 50 percent of the island’s land area

(Fig. 1). The highest points of the Cordillera Central are in the south and most rivers flow

south to north, emptying on the north coast. Between the mountainous interior and coast are

foothills that amount to 25 percent of the island’s surface area. Surrounding the Cordillera

Central and its foothills is a thin, flat alluvial plain that makes up the remaining 25 percent of

the land surface and holds the island’s best soils.

19 Stuart B. Schwartz, ‘The Hurricane of San Ciriaco: Disaster, Politics, and Society in Puerto Rico, 1899-1901,’ Hispanic American Historical Review, 72:3 (1992): 303-334. 20 Schwartz, Sea of Storms: A History of Hurricanes in the Greater Caribbean from Columbus to Katrina (Princeton: Princeton University Press, 2015).


www.whpress.co.uk

Figure 1. Shaded Relief Map of Puerto Rico. Source: US Geological Survey, available at: https://pr.water.usgs.gov/public/gis_map.html . Irrigation district outline added by author.

Puerto Rico has a tropical climate and the north-east trade winds supply the north and

central parts of the island with heavy rainfall for half the year. However, rain does not fall in

such high quantities on the southern coastal plains, which sit in the rain shadow of the

Cordillera Central (Fig. 2). Although south-eastern soils were excellent for agriculture, they

lacked sufficient water for large-scale cultivation. Redistributing water from the mountains to

the relatively dry plains held great promise and excited the imagination of irrigation

enthusiasts, but no such project garnered support under Spanish rule.21 In 1866, English

engineer E.B. Webb proposed damming Rio La Plata at a site known as Carite Valley and

diverting the water south, through a tunnel in the mountains, to irrigate the southern coastal

21 Spain’s eager embrace of irrigation dams came only in the twentieth century. See Erik Swyngedouw, Liquid Power: Contested Hydro-Modernities in Twentieth-Century Spain (Cambridge: MIT Press, 2015).


www.whpress.co.uk plains. The Spanish government approved the scheme but never built it.22

Figure 2. Mean Annual Rainfall of Puerto Rico, 1981-2010. Source: National Weather Service, ‘Map of Puerto Rico and USVI Mean Annual Rainfall (1981-2010),’ available at www.weather.gov/sju/hydrology. The darkly shaded areas along the southern coast receive relatively little rain (25-45 inches per year). The north-east, by contrast, receives upwards of 170 inches per year. Although rainfall averages here date from 1981 to 2010, rainfall distribution patterns are likely very similar to what they were in the early-twentieth century. Rainfall patterns are influenced by the mountains and prevailing wind patterns which remain mostly unchanged. (Note: the original edition of this map includes rainfall averages for the US Virgin Islands which the author has removed).

Changing economic conditions after the 1898 Spanish-American War helped rekindle

interest in irrigation. In 1901, the US government removed the tariff on Puerto Rican sugar,

provoking a boom in cultivation.23 North American sugar companies flooded the island with

capital and cane quickly became the principal export and economic activity, giving Puerto

Rican and North American azucareros greater political influence on the island.24 Sugar was

22 Annual Report of the Governor of Porto Rico, 1919, 509-510, AGPR, Annual Reports. 23 Dietz, Economic History of Puerto Rico, pp. 103-104. 24 Ayala and Bernabe, Puerto Rico in the American Century, pp. 35-41.


www.whpress.co.uk booming, but recurring drought in the south-east after 1898 hindered azucareros’ efforts

there. They saw reviving Webb’s irrigation scheme as the solution.

The azucareros’ irrigation plans found a receptive political climate after 1898, when

the US government took over administrative control of Puerto Rico. Under the colonial

administration, the president appointed the governor and his cabinet, which meant that Puerto

Ricans had minimal political participation. Legislation was designed and implemented to

favor American corporate interests.

The SCIP was no exception. It would water the canefields of Aguirre Sugar Co., one

of four large, vertically-integrated North American corporations in Puerto Rico, all

concentrated in the south and east, that together produced 50 percent of the island’s cane in

the first decades of the twentieth century. Taxes on irrigation water, the primary means of

generating revenue to meet the SCIP’s bond payments, made irrigation expensive, but

Aguirre had the capital to foot the bill. Indeed, after the project was completed Aguirre

profited immensely and had no problem meeting payments. The company came to own or

lease 15,783 of the irrigation district’s 19,425 hectares and ran the south-east’s three largest

industrial sugar mills, known as centrales: Aguirre, Machete and Cortada.25 The Foraker

(1900) and Jones Acts (1917) limited the amount of land that a corporation could hold to 202

hectares, but this provision was widely ignored until the 1930s and 1940s.26 Thus, the

colonial government’s irrigation system was designed to shore up profits for a North

American corporation.

The Puerto Rican government began studying south coast irrigation in March 1907. In

April 1908, they created the Irrigation Service, and in September that year issued bonds for

25 North American dominance was regional. In the north and west large sugar mills and canefields were mostly owned by Puerto Rican azucareros, but in the south and east, North American companies dominated. For more on Central Aguirre Sugar Co. see: Manual of the Sugar Cane Companies, (New York: Farr & Co., 1935), 12-15; Ayala, American Sugar Kingdom, pp. 108-111, 226; Bernabe, ‘Prehistory of the Partido Popular Democrático,’ pp. 52-53, 56-60. 26 Ayala and Bernabe, Puerto Rico in the American Century, p. 37. Ayala and Berbabe note that such disregard showed the political weight that sugar interests had among the US officials appointed to administer Puerto Rico.


www.whpress.co.uk further surveys of the island’s first major irrigation project, to be carried out by engineers of

the US Reclamation Service.27 The project, which became the SCIP, was the first ambitious

irrigation scheme on the island and entailed the construction of the first three large dams built

with reinforced concrete. It was undertaken with the explicit purpose of irrigating

canefields.28 When finished in 1914, the SCIP’s three large dams created the first large

standing bodies of fresh water on an island that has no natural lakes (Fig. 3).

Figure 3. Map drawn in 1911 showing principal features of the South Coast Irrigation Project. Source: Porto Rico Irrigation Service, ‘Sketch Map Showing Principal Features,’ 1911, Archivo General de Puerto Rico, Series: Irrigation, Record Group: Public Works, Box 509, Folder 1.

By the mid-1920s, the SCIP was irrigating 19,425 hectares on Puerto Rico’s south-

eastern alluvial floodplain. The floodplain totaled 30,351 hectares, 64 kilometers in length

and no more than 5 kilometers in width.29 The project was divided into eastern and western

sections and consisted of three principal dams and two much smaller ones. The Guayabal 27 Eugenio Latimer Torres, Historia de la autoridad de energía eléctrica: implantación de los sistemas de luz y fuerza en Puerto Rico, 1893-1993 (San Juan: Autoridad de Energía Eléctrica, 1997), pp. 229-273. 28 The project was led by James Beardsley. Raised in New York, Beardsley received a degree in civil engineering from Cornell University in 1891. Between 1910 and 1916 he was the chief engineer of the Puerto Rican Irrigation Service, where he oversaw the construction of the SCIP. See: Willi H. Hager, Hydraulicians in the USA 1800-2000: A Biographical Dictionary of Leaders in Hydraulic Engineering and Fluid Mechanics (Boca Raton, FL: CRC Press, 2015), p. 1819. 29 Antonio Lucchetti to Miguel Muñoz, 26 Dec. 1927, NARA II, RG 350, Records of the Bureau of Insular Affairs, Series: General Classified Files, 1898-1945 (hereafter GCF), Box 10.


www.whpress.co.uk Dam, the chief feature of the western section, had a reservoir with a storage capacity of

around 1,172 hectare-meters. Carite, one the two main dams of the eastern section had a

similar storage capacity. Patillas, the second dam in the eastern section, was the biggest and

most expensive dam of the entire project with a storage capacity of 1,792 hectare-meters.30 In

1914, the year the SCIP was completed, the governor of Puerto Rico wrote with pride to the

Secretary of War that the last of the project’s dams stood completed and ‘its gates were

opened and its canals filled with water for the thirsty sugar lands.’31

The thirst, however, remained unquenched. Droughts and dry periods reduced rainfall

at the same time that sediments filled the reservoirs and reduced storage capacity (see below).

Azucareros looked to groundwater for the solution.32 Groundwater pumps needed electricity,

which was costly on an island that had no oil or coal deposits. The Carite Dam offered a

solution. Two turbines were installed at Carite as part of the irrigation system, providing an

affordable source of energy to the south coast azucareros. Groundwater pumps soon became

a ubiquitous feature of the south-eastern coastal plain.33

Although the two hydroelectric plants at Carite were byproducts of a system whose

primary purpose was surface water irrigation, they soon became an integral part of achieving

that end. Antonio S. Lucchetti, Chief Engineer of the Irrigation Service from 1923 to 1932,

remarked that, ‘our Irrigation System may well be considered a combined gravity and

30 Lucchetti, ‘Irrigation and Hydroelectric Systems of the South Coast of Porto Rico,’ in A.B. Gilmore, (ed.) The Porto Rico Sugar Manual, 1930-1931 (New Orleans: Gilmore, n.d.), pp. 32-40. 31 Annual Report of the Governor of Porto Rico, 1914, 42, AGPR, Annual Reports. 32 Lucchetti, ‘Irrigation and Hydroelectric Systems of the South Coast of Porto Rico,’ p. 34. 33 Groundwater pumping from the South Coast Aquifer was not measured until the 1960s, so it is difficult to discern what impact pumping during the sugar boom had on groundwater supplies. Subsequent reports do note that seepage from the SCIP’s irrigation canals likely augmented groundwater supplies, so some of the lost surface water was recovered, but only with the added expense of pumping it from the aquifer. There does not appear to have been any laws that restricted groundwater pumping, meaning that azucareros were free to pump as much as they could when surface water supplies ran short. For more on the South Coast Aquifer, see: Thalia D. Veve and Bruce E. Taggart, eds., Atlas of Ground-Water Resources in Puerto Rico and the U.S. Virgin Islands, Water Resource Investigations Report 94-4198 (Denver, CO: United States Geologic Survey, 1996); Perry G. Olcott, ‘Puerto Rico and the U.S. Virgin Islands,’ in Ground Water Atlas of the United States: Alaska, Hawaii, Puerto Rico and the U.S. Virgin Islands, Report HA 730-N, (Denver, CO: United States Geologic Survey, 1999).


www.whpress.co.uk pumping system.’34 In Central Aguirre, the largest sugar central on the southern coastal plain,

for example, 40 percent of the water used was from surface water and 60 percent from

pumping stations operated by electricity even when the Irrigation Service delivered its full

quota.35 Groundwater pumps also allowed azucareros to expand their operations across 6,070

new hectares, bumping the total area under irrigation from 13,355 to 19,425 hectares.36 Thus

the irrigation system harnessed not just surface water, but all the groundwater it could pump,

which was just enough to fill irrigation canals and save the sugar boom.

The dams failed to mobilize the island’s water resources as the azucareros and

engineers had hoped. In 1913 Arthur Yager, the Governor of Puerto Rico, wrote that ‘the

great problem of the planters was a dependable, artificial supply of water that could be

controlled for storage, or use, according to the variations in the natural supply.’ Confident in

the abilities of his engineers, the Governor continued: ‘it is estimated that the normal flow

and the floods…will be so controlled and distributed as to be converted into valuable crop

producing factors throughout the irrigation district.’37 Despite the Governor’s vision, the

engineers and azucareros that supported the SCIP vastly overestimated their ability to

manage Puerto Rico’s surface water.

The turn towards groundwater pumps is itself evidence of this. In 1932, Marcelo J.

Oben, the field manager for Central Aguirre, argued that azucareros had installed more

pumping stations because the Irrigation Service failed to bring in sufficient water during

prolonged droughts. Oben claimed that during annual and extended dry periods, surface

water was in short supply and during the worst droughts reservoirs were emptied altogether.38

34 Lucchetti, ‘Irrigation and Hydroelectric Systems of the South Coast of Porto Rico,’ p. 34. 35 In addition to the main central at Aguirre, the Central Aguirre Sugar Co. also owned the second and third largest centrales in the south-east, Machete and Cortada. For more on Central Aguirre Sugar Co. see: Manual of the Sugar Cane Companies, (New York: Farr & Co., 1935), 12-15; Ayala, American Sugar Kingdom, 108-111, 226; Marcelo J. Oben, ‘Cultivation of Sugar Cane in the South Side of the Island of Porto Rico,’ in A.B. Gilmore (ed.) The Porto Rico Sugar Manual 1932-33 (New Orleans: Gilmore, n.d.), pp. 38-40. 36 Memorandum RE: Irrigation System on the South Coast of Puerto Rico, 26 Dec. 1927, NARA II, RG 350, Series: GCF, Box 10. 37 Annual Report of the Governor of Porto Rico 1913, 53, AGPR, Annual Reports. 38 Oben, ‘Cultivation of Sugar Cane in the South Side of the Island of Porto Rico,’ p. 39.


www.whpress.co.uk Irrigation Service engineers admitted as much. The records from the Irrigation Service are

rife with statements discussing recurrent suspension of water deliveries. For example, in 1921

a frustrated group of azucareros wrote Irrigation Service engineer Lucchetti to complain

about water shortages. Lucchetti responded that there was nothing he could do to resume

water deliveries because of ‘the fact that the reservoir has dried completely.’39 In 1952 the

Irrigation Service noted in its Annual Report that the water deliveries from the Patillas Canal

were once again suspended because there was no water in the reservoir.40 The laments from

the azucareros and engineers echo those of former Chief Engineer James Beardsley. In 1910,

he had criticized the small irrigation systems put in place by the Spanish before 1898 because

they ‘depended entirely upon the flow of the stream and were useless during the periods of

greatest need.’41 The SCIP brought in more water by volume but the reservoirs were just as

susceptible to the cycles of drought as previous small irrigation systems.

Economic and Social Consequences

To be sure, the dams and reservoirs provided a huge boon to the sugar industry. Even

though the azucareros complained that the water was insufficient, the groundwater was

enough to provide the desired growth in crop production. From 1909 to 1915 the average

annual sugar harvest in the lands to be irrigated was approximately 54,000 tons. From 1916

to 1930 the average in the south-eastern irrigation district reached 104,000 tons. 42 Sugar

production declined in the immediate aftermath of the 1929 financial crisis, but recovered 39 Lucchetti, ingeniero jefe, a los regantes que se surten de agua del canal de Juana Díaz, 27 April 1921, AGPR, Series: Irrigation (Aguas), RG: Public Works (Obras Públicas), Box 509. [Author’s translation]. 40 Annual Report of the Puerto Rican Water Resources Authority, 1952-53, 82, Archivo Histórico de la Autoridad de Energía Eléctrica, Guaynabo, Puerto Rico (hereafter AHAEE), Annual Reports. 41 Beardsley, Bulletin 18, 1910, 2, NARA II, RG 350, Series: GCF, Box 10. 42 Azucareros also increased the harvest by switching to high sucrose cane varieties, which began in the effort to find strains resistant to cane mosaic disease in the late 1910s. Lucchetti, ‘Irrigation and Hydroelectric Systems of the South Coast of Porto Rico,’ 1930, 34. Stuart McCook argues convincingly that varietal shifts were the most important factor for production increases throughout the island, but irrigation mattered more in the south-east. He himself notes that Aguirre traditionally planted varieties of cane less susceptible to mosaic disease and were not compelled to plant high-yielding alternatives until much later. See: Stuart McCook, States of Nature: Science, Agriculture, and Environment in the Spanish Caribbean (Austin, TX: University of Texas Press), p. 96.


www.whpress.co.uk shortly thereafter. In 1934, Central Aguirre Sugar Co. and its subsidiaries and affiliates

produced 130,240 tons of sugar, earning a net income of upwards of US$2 million and

bringing their total surplus to over US$10 million.43

In 1948 Sidney Mintz, who was living and doing research in Barrio Jauca on the

southern coast of Puerto Rico, remarked on the exuberant growth of the canefields. He wrote

that as the cane matured it turned the coastal plain into ‘a hot, impenetrable jungle, broken

only by special pathways and irrigation ditches...all the time I was in Barrio Jauca, I felt as if

we were on an island, floating in a sea of cane.’44 Although he wrote in the 1940s, Mintz’s

remarks are undoubtedly fitting for the 1920s and 1930s as well. Irrigation had turned the

south-eastern coastal plain into a giant canefield.

The sugar boom in south-eastern Puerto Rico was part of an expansion in sugarcane

production throughout the Caribbean between 1898 and 1934. Increasing US capital and

influence in Cuba and Puerto Rico after the Spanish-American War contributed to this

growth. Furthermore, World War One destroyed much of the European sugar beet industry,

which had competed with Caribbean cane sugar since the middle of the nineteenth century. In

1921 Cuba, the Dominican Republic, and Puerto Rico together produced 38 percent of the

world’s cane sugar and 27 percent of all sugar produced.45 Although Cuba accounted for

most of this production, Puerto Rican sugar held a large share of the US market because it

entered the United States tariff-free. By the 1930s, Puerto Rico provided around 15 percent of

the raw sugar in the US market.46

The sugar boom was important for the SCIP because dam construction was expensive.

Taxes on sugar provided essential revenue used to repay loans. Not only was the overhead

43 Manual of the Sugar Cane Companies, (New York: Farr & Co., 1935), 13. This publication lists Central Aguirre Sugar Co. and its subsidiaries and affiliates’ net income that year as US$2,198,508 and their total surplus as US$10,157,124. 44 Sidney Mintz, Sweetness and Power: The Place of Sugar in Modern History (New York: Viking, 1985), p. xviii. 45 Ayala, American Sugar Kingdom, p. 187. 46 Ayala and Bernabe, Puerto Rico in the American Century, p. 38.


www.whpress.co.uk cost of the project high, it took US$60,000 per year to maintain and repair the dams.47

Irrigation water in Puerto Rico cost US$15 per hectare-meter per year, which was double the

average cost in US Reclamation Service projects in the American West.48 In the 1930s Oben

calculated that irrigation was the single most expensive item for sugar companies,

constituting 40% of total budget expenditures.49 Yet, high returns from the booming sugar

economy made irrigation worthwhile and the Irrigation Service collected sufficient money in

taxes to meet the annual payments for the SCIP.50 Although these azucareros were willing,

and indeed expected, to pay a high tax on irrigation water, unforeseen developments

subsidized the costs and reduced their tax payments. For a second time the installation of

hydroelectric turbines at the Carite Dam provided unforeseen benefits to the azucareros.

Sales of hydroelectricity became the dominant method of that the Irrigation Service

repaid the SCIP’s bonds in the 1920s and 1930s and, as a result, they reduced the irrigation

tax. The two primary ways in which the Irrigation Service expected to generate revenue to

repay loans was through water taxes and sales of excess water. However, as groundwater

pumps proliferated, and the south coast began electrifying its towns and cities, sales of

electricity grew and surpassed irrigation taxes as principal means of meeting payment

schedules. In 1929, the irrigation water tax contributed US$293,000 to debt repayments while

sales of electric power in the district amounted to US$432,000.51 Electricity sales did not just

help pay back loans, they increasingly subsidized the azucareros’ water. The water tax was

US$15 per hectare-meter per year from 1914 to 1922. From 1922 to 1930 the tax decreased

gradually to US$11.25 per hectare-meter per year, because of ‘the large increase in the

47 The project’s total cost upon completion in 1914 was US$5.1 million. Torres, Historia de la Autoridad de Energía Eléctrica, 1997, p. 261. 48 Beardsley to the Commissioner of the Interior, 23 May 1916, AGPR, Series: Irrigation, RG: Public Works, Box 509. 49 Oben, ‘Cultivation of Sugar Cane in the South Side of the Island of Porto Rico,’ 1932, p. 39. 50 Lucchetti, ‘Irrigation and Hydroelectric Systems of the South Coast of Porto Rico,’ 1930, p. 34. 51 Ibid.


www.whpress.co.uk income from the electrical business.’52 In 1933, the water tax dropped even further to

US$7.59, nearly half of what it was a decade prior.53 Thus the hydroelectric plants, which

were constructed as an incidental part of the irrigation system, came to be essential not only

for supplying groundwater but also for providing revenue to make the dams profitable.

Although none anticipated the extent to which power sales would be essential to

generating revenue, some did anticipate growth in the electricity market. Between 1898 and

1914 Puerto Rico, along with the mainland United States, began electrifying its cities and

industries. Governor Yager wrote in 1915 that ‘there is every reason to believe that several

towns on the south side, including Guayama and Salinas, will soon modernize their public

and private lighting by the introduction of electricity.’54 Nevertheless, the Irrigation Service

was apprehensive. Beardsley remarked in 1915, that it would be a poor idea to build another

power plant at that time because the ‘development of such a market will probably be the

work of at least a few years.’55 Electricity sales were not included in the original repayment

plans for the SCIP and it was not until after the Carite plant was finished that engineers

realized the lucrative potential of burgeoning energy markets for municipal electrification and

azucarero groundwater pumps. Revenues from hydroelectric power sales in 1920 ‘greatly

exceeded all of the original estimates.’56 The Carite power plant became an essential

component of the system because it provided both affordable groundwater and a lucrative

source of revenue for the Irrigation Service.57

52 Ibid. 53 Annual Report of the Utilization of Water Resources and Puerto Rico Irrigation Service (South Coast), Fiscal Year 1932-33, 112, NARA II, RG 350, Series: GCF, Box 11. 54 Annual Report of the Governor of Porto Rico, 1915, 295-296, AGPR, Annual Reports. 55 Beardsley to the Commissioner of the Interior, 3 April 1915, AGPR, Series: Irrigation, RG: Public Works, Box 509. 56 Annual Report to the Governor of Porto Rico, 1920, 42, AGPR, Annual Reports. 57 The Carite power plant was the beginning of a public power company that became the Autoridad de Energía Eléctrica, the agency that now owns the SCIP dams. See: Torres, Historia de la Autoridad de Energía Eléctrica, 1997.


www.whpress.co.uk Azucareros profited from sugarcane, but the wealth did comparatively little to

increase the standard of living for fieldworkers and the rural poor.58 Inequalities in land

ownership may have been a legacy of Spanish rule, but the sugar boom furthered these

inequalities by concentrating land on Puerto Rico’s coastal plains among large sugar

companies.59 In the south-east, land concentration was exacerbated by the irrigation tax,

which raised rent and forced Puerto Ricans to sell their land to large North American sugar

corporations. As a result, landlessness was rife and most of the south-east coastal plain came

under corporate control. For example, 99 percent of the cropland in the municipality of Santa

Isabela was owned or leased by the Aguirre Sugar Co (whose landholdings on the south-east

are discussed above).60

Small farmers who did own land often still depended on the large centrales for their

livelihood. Although much of the cane processed in the south-east’s large centrales was

grown on land owned or leased by Central Aguirre, around 10 percent of it was cultivated by

smaller producers known as colonos.61 They owned their own land, but the irrigation tax

made it necessary to cultivate relatively lucrative sugarcane, and the colonos depended on

centrales to grind it.

For much of the landless population, labor in corporate-owned canefields became

their only means of livelihood. In 1914, sugarcane workers made an average daily wage of 54

cents. Earnings increased some as sugar boomed in the following years, but in 1916 the

Bureau of Labor reported that, despite rising wages, the ‘increase granted was not in

proportion to the unprecedented price the employers were receiving for sugar.’62 In some

cases strikes were successful in raising wages. Yet, even as wages increased so too did the 58 Central Aguirre’s canefields, mills, and company town were characterized by socioeconomic hierarchies in which North American managers and technicians occupied the topmost position, followed by upper-middle-class Puerto Rican managers, technicians, and government employees, and finally, Puerto Rican field and mill workers. See: Sam R. Sweitz, ‘The Production and Negotiation of Working-Class Space and Place at Central Aguirre, Puerto Rico,’ Journal of the Society for Industrial Archeology, 36 (1) 2010: 24-46, 38. 59 Ayala and Bergad, ‘Rural Puerto Rico in the Early Twentieth Century Reconsidered,’ 2002. 60 Bernabe, ‘Prehistory of the Partido Popular Democrático,’ 1989. 61 Ibid. 62 Annual Report of the Governor of Porto Rico, 1916, 442, AGPR, Annual Reports.


www.whpress.co.uk cost of living. In 1925 the Bureau of Labor reported that ‘in the last ten years the cost of the

sugar laborers’ diet has increased 48.6 percent while his wages have increased but 26.5

percent.’63 Although irrigated sugar lands brought bigger harvests and profits for azucareros,

workers’ wages remained low.

Government reports from the 1930s give a good indication of how little purchasing

power these wages yielded. According to the Bureau of Labor, in 1931 the average daily

wage of sugarcane workers had increased to 75 cents.64 Since families on sugar estates

averaged around 5 members per household, this meant an average of 15 cents a day for each

family member.65 In the 1930s the Puerto Rican Reconstruction Administration stated that

supplying one person’s basic food requirements required 20 cents a day.66 Thus, on average,

households that relied on a single wage earner were 25 cents short of meeting their daily

nutritional requirements even if they spent all their money on food. For families that had

more than one wage earner, prospects were somewhat better, but their earnings still scarcely

covered their sustenance needs. In 1937 the Puerto Rican Construction Administration

reported that 65 percent of wages from laboring families on a south-eastern sugar plantation

was spent on food, ‘a sure indication of the inadequacy of an income of which such a high

proportion has to be devoted to mere subsistence.’67 On other estates this percentage was as

high as 90 percent.68

Moreover, labor was seasonal, which meant that most fieldworkers were only

employed six months of the year. Thus, wages earned during the harvest had to stretch across

the entire year. Mintz recounted the seasonal rhythms in Barrio Jauca and noted that during 63 Annual Report of the Governor of Porto Rico, 1925, 35, AGPR, Annual Reports. 64 Annual Report of the Governor of Porto Rico, 1931, 94, AGPR, Annual Reports. 65 Rafael Bernabe confirmed these numbers in this study. He argued that weekly wages for cane workers amounted to 14 cents a day for each family member. See: Bernabe, ‘Prehistory of the Partido Popular Democrático,’ 1989. 66 Ibid. 67 Morales Otero, et al., ‘Health and Socioeconomic Conditions on a Sugar Cane Plantation,’ June 1937, 68, Health Division, Puerto Rico Reconstruction Administration and the School of Tropical Medicine, San Juan, Puerto Rico, Box 12, RG 323, Records of the Puerto Rican Reconstruction Administration, National Archives New York City. 68 Bernabe, ‘Prehistory of the Partido Popular Democrático,’ 1989.


www.whpress.co.uk the off season the ‘little account books each Puerto Rican family has for its food purchases

begin to carry more unpaid entries.’69 The irrigation water harnessed by the SCIP generated

tidy profits for the Central Aguirre Sugar Co., but Puerto Rican fieldworkers did not share

this wealth.

Erosion and Sedimentation

In contrast to the welcome, if unexpected, benefits of electrification, another

unintended consequence of dam construction troubled both engineers and azucareros: erosion

and the accumulation of sediment in reservoirs. Sedimentation is one of the most important

issues associated with dam construction because it reduces the lifespan of reservoirs. In

addition to the important roles that river water plays in supporting life on earth, rivers are also

chief actors in the rock cycle. Rivers transport rocks and soil to the ocean where they are

deposited as sediment. When a dam is constructed, the rock cycle is stalled, and sediment is

deposited behind the dam rather than carried to the ocean. The rate of sedimentation in any

reservoir depends the dam’s engineering, local climate and rainfall patterns, the topography

of the reservoir’s watershed, and the land use and farming practices in the basin. In Puerto

Rico, these conditions generally encouraged high rates of erosion and sedimentation.

Weather was a principal concern to the engineers overseeing the construction of the

SCIP. The engineers who surveyed the reservoir sites were from the semi-arid American

West, with no experience building dams in tropical climates. In 1908, US Reclamation

Service Chief Engineer (and soon to be director) Arthur Powell Davis surveyed the SCIP’s

dam sites in southern Puerto Rico. He noted that ‘conditions as regards heavy rainfall have no

parallel within the limits of the United States, and conclusions based upon the latter cannot be

considered as a safe guide.’70 In addition to heavy seasonal rainfall, engineers also had to

69 Mintz, Worker in the Cane, 1960, p. 20. 70 A.P. Davis and D.C. Henny to F.H. Newell, 19 March 1909, 14-15, NARA II, RG 350, Series: GCF, Box 10.


www.whpress.co.uk account for hurricanes, whose strong winds and rains battered the dams and flooded the

island’s rivers.

The SCIP dams held up well against severe weather.71 In 1928 and 1932, two

hurricanes devastated the island. During the 1928 hurricane, Horace Towner, governor of

Puerto Rico, reported 40 inches of rainfall in 48 hours in the mountainous interior and severe

flooding in coastal towns.72 The 1932 hurricane inflicted further damage. But in 1932, the

Irrigation Service carried out only US$2,500 worth of work to repair damage from the

hurricane that year, and their annual report does not mention major structural harm.73 While

lack of evidence to the contrary may seem insufficient to prove that dams sustained little

damage from hurricanes, annual reports consistently documented damage from flooding in

other years.74 Hurricanes were detrimental to Puerto Rican agriculture and economies but

apparently did not inflict major structural damage on the dams and reservoirs themselves.

However, hurricanes did, along with high average rainfalls, contribute to high levels of

erosion that led to increased sedimentation in the reservoirs.

Sedimentation of Lago Guayabal, the westernmost of the three large reservoirs that

formed the SCIP, was first noticed in 1920. Three large floods between 22 August and 4

September delivered large amounts of silt and debris to the reservoir. The mud sitting at the

bottom of the reservoir measured 30 feet deep and clogged the sluice gates controlling water

deliveries. Lucchetti and other Irrigation Service engineers worked to clean the reservoir but

were unsuccessful. It was difficult to remove sediments while the reservoir remained full and

71 In 2017, Hurricane Maria showed that Puerto Rico’s dams may fare worse in future storms unless the government funds expensive maintenance work. Maria ripped a hole in the spillway of Guajataca Dam, a reservoir the Irrigation Service built in the 1920s to water canefields in the north-west. The SCIP’s dams fared better, but like Guajataca they are aging and desperately need maintenance. 72 Schwartz, Sea of Storms, p. 233. 73 Annual Report of the Utilization of Water Resources and Puerto Rico Irrigation Service (South Coast), Fiscal Year 1932-33, NARA II, RG 350, Series: GCF, Box 11. It is possible that more damage was reported the following year, but the 1933 Annual Report of the Governor is not available at AGPR and NARA II, nor through ProQuest Congressional. 74 For example, on 3 Jan. 1937 the Patillas River flooded and damaged a large part of the Patillas spillway. It cost the irrigation service over US$11,000 in repairs. See: Annual Report of the Utilization of Water Resources and Puerto Rico Irrigation Service (South Coast), Fiscal Year 1936-1937, NARA II, RG 126, Series CF, Box 1001.


www.whpress.co.uk further flooding frustrated their efforts.75 As a result, the Irrigation Service had to cut water

deliveries significantly. The installation of a siphon allowed the smallest quantities of water

to reach irrigators but most of their irrigation water sat behind the plugged sluice gates.

Irrigation Service engineers soon realized that the only effective way to clean the

gates and make the necessary repairs was to drain the reservoir completely. But stopping

water deliveries would spell financial disaster to the azucareros and to the Irrigation Service

that depended on their tax revenue. Reflecting on the situation in 1921, Chief Engineer F.A.

Murray wrote: ‘with sugar at US$22.00 per 100 lbs. and 10,500 acres [4,250 hectares] of

growing cane in jeopardy, the situation was desperate in the extreme.’76 Thus, the engineers

decided not to drain the reservoir. Instead they pumped water through the siphon and waited

until seasonal droughts drained the reservoir naturally. In an ironic twist, seasonal droughts,

the undesirable weather condition that the irrigation engineers fought so hard to overcome,

became a temporary salvation of the Irrigation Service.

Droughts over the following two years allowed the Irrigation Service to make the

necessary repairs on the sluice gates at Lago Guayabal (Fig. 4). Seasonal floods prolonged

the repair work, but on 23 August 1922 the reservoir was completely emptied, and new sluice

gates were installed that could handle large sediment burdens.77 Thereafter the Irrigation

Service resumed its water deliveries. Although the short-term siltation issue at Lago

Guayabal was resolved, the floods made it clear that in the long term large burdens of silt

would reduce the storage capacity of reservoirs.

75 F.A. Murray a los regantes que se surten de agua del canal de Juana Díaz, AGPR, Series: Irrigation, RG: Public Works, Box 511. 76 F.A. Murray to Ambursen Construction Co., 11 Feb. 1921, AGPR, Series: Irrigation, RG: Public Works, Box 511. 77 Lucchetti a Los regantes que se surten de agua del canal de Juana Díaz, 27 April 1921, AGPR, Series: Irrigation, RG: Public Works, Box 511.


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Figure 4. Photographs taken in 1921 showing sedimentation in Lago Guayabal and efforts to clean the sluice gates. Source: Archivo General de Puerto Rico, Series: Irrigation, Record Group: Public Works, Box 511, Folder 1.

There was little concern about siltation in the planning stages of the project. The

initial reports produced by the Bureau of Reclamation engineers who surveyed dam sites do

not mention sedimentation and engineers did not anticipate that silting would constrain water

deliveries to azucareros. In 1921, chief engineer F.A. Murray commented that ‘apparently,

when the present sluice gates were designed, it was not anticipated that there would be such a

large amount of silt and debris brought by the river into the reservoir, so no provision was

made to dispose of the accumulations.’78 It is not entirely clear why these engineers

overlooked rapid sedimentation, but it is likely that a combination of inexperience with

tropical environments and the priorities of the imperial government funding them—which

78 F.A. Murray to Ambursen Construction Co., 11 Feb. 1921, AGPR, Series: Irrigation, RG: Public Works, Box 511.


www.whpress.co.uk encouraged fast construction and discouraged long-term thinking—led these engineers to

underestimate the severity of siltation.

The 1920 floods brought long-term sedimentation to their attention. Lucchetti was

optimistic that short-term sediment problems could be easily resolved, but was unsure what

to do about the long-term consequences. It appears that neither him nor other Irrigation

Service engineers had seriously considered the problem. In correspondence with the

construction company repairing Lago Guayabal, Lucchetti wrote: ‘as to the larger problem of

removing the silt in the reservoir to conserve its storage capacity, we will have to make a

further study of the situation.’79 Sedimentation was a huge threat because it endangered the

longevity of the project by reducing available water, hampering cane production, and cutting

Irrigation Service revenues.

Siltation became an even greater problem in the following decades. By the mid-

1930s, half of Lago Guayabal was filled with sediment.80 This pained the azucareros who

watched half the water they had been expecting for their canefields topple over the

floodgates. The azucareros came up with two simple solutions: dredge the reservoir and build

another dam on an upstream tributary. But dredging was expensive and their request for a

loan failed to gain support in Congress in the tight-budget 1930s.81 However, the azucareros

were persistent and budgets soon loosened. Between 1942 and 1947 the Irrigation Service

dredged Lago Guayabal and removed over 750,000 cubic meters of sediment. They also

raised the dam’s height, adding an additional 1,147 hectare-meters to the reservoir’s storage

capacity.82 These measures purchased a respite from the costs of sedimentation but could not

do so forever. In 1972, the Puerto Rican Aqueduct and Sewer Authority built a second dam,

Toa Vaca, just upstream from Lago Guayabal on a tributary to the Jacaguas River. The dam

79 Lucchetti to Ambursen Construction Co., 5 May 1921, AGPR, Series: Irrigation, RG: Public Works, Box 511. 80 Annual Report of the Utilization of Water Resources and Puerto Rico Irrigation Service (South Coast), Fiscal Year 1937-38, 6-7, NARA II, RG 126, Series CF, Box 1001. 81 Ibid., 9. 82 Annual Report of the Puerto Rico Water Resources Authority, Fiscal Year 1946-47, 42, NARA II, RG 126, Series CF, Box 1001.


www.whpress.co.uk was built to ease the sedimentation load of Lago Guayabal and provide additional irrigation

water.83 The dam did ease the sediment burden of the reservoir, but it did not eliminate the

siltation problem. In 2001, Lago Guayabal had 6.12 million cubic meters of its original 11.82

million cubic meters of storage capacity remaining. Once again nearly half of the reservoir

was filled with sediment.84

The rapid sedimentation of Lago Guayabal was a result of natural erosion as well as

human actions and land use practices. Erosion rates are influenced by a variety of natural

factors including soil quality, weathering (wind and water), and topography (the grade of

slope). In the case of watersheds another important consideration is the drainage density, that

is, how large or small an area is drained by a river and its tributaries. In watersheds with a

high drainage density, such as those in Puerto Rico, sediment is carried quickly from smaller

tributaries near agricultural plots to the main stem of a river.

Puerto Rico’s steep topography, the high drainage density of the island’s watersheds,

and heavy weathering resulting from storms, all encouraged high rates of erosion.85 Soils in

the interior of the island were often deep and porous and could retain moisture, but steep

slopes made them highly vulnerable to erosion during heavy rains and hurricanes. After

surveying the island’s soils in the 1930s, US Department of Agriculture soil scientist W.W.

Pate concluded that the slopes on the southernmost mountains were ‘so steep that

considerable erosion would go on regardless of the activity of man.’86 Thus, natural erosion

produced much of the sediment that accumulated in Lago Guayabal. However, that the

reservoir was filled with so much sediment so quickly was not the result of nature alone. In

83Luis R. Soler-López, Sedimentation Survey of Toa Vaca, Puerto Rico, Scientific Investigations Report 2004-5035, United States Geologic Survey (hereafter USGS), 2002. 84 Luis R. Soler-López, Sedimentation History of Lago Guayabal, Puerto Rico, 1913-2001, Water Resource Investigations Report 03-4198, USGS, 2001. 85 W.W. Pate, M.E. Stephens, and Jorge Landron, ‘Reconnaissance Erosion Survey – Puerto Rico,’ Soil Conservation Service, US Department of Agriculture, 1935, NARA II, RG 126, Series CF, Box 797. 86 Ibid., pp. 23-24.


www.whpress.co.uk Puerto Rico there was an additional factor to consider: cash crops on mountain slopes in the

watershed of Lago Guayabal, which greatly exacerbated high rates of natural erosion.87

Intensive coffee and sugarcane production on steep slopes of the island’s interior

contributed to erosion in the Lago Guayabal drainage basin during the 1920s and 1930s. In

the last two decades of the nineteenth century, Puerto Rico’s interior highlands were

overtaken by export-oriented monocultures. Both tobacco and coffee featured prominently in

this boom, but coffee had a more enduring influence on erosion in Lago Guayabal’s

watershed (Fig. 5). The golden age of coffee production in Puerto Rico was between 1885

and 1898, the period between the abolition of slavery and the Spanish-American War.88 With

the US occupation in 1898 the situation changed. Sugar became the island’s dominant export

crop and surpassed coffee in economic importance.89 Although the relative value of coffee

declined, cultivated area did not. The Department of Agriculture estimated that just prior to

American occupation in 1898 coffee covered 72,843 hectares. In 1919, 78,331 hectares of

87 Ibid. 88 Dietz, Economic History of Puerto Rico, pp. 64-69. 89 Ibid., pp. 196-198.


www.whpress.co.uk coffee were harvested.90

Figure 5. Map showing predominant land use in the west-central mountainous areas of Puerto Rico during the mid-twentieth century. Although land use patterns here are from the 1940s and 1950s, it is very likely that coffee would have been cultivated across a similar or even larger area between 1898 and 1920 as well. Source: Luis R. Soler-López, Sedimentation History of Lago Guayabal, Puerto Rico, 1913-2001, Water Resource Investigations Report 03-4198, USGS, 2001.

The erosive potential of coffee cultivation was initially mitigated by the fact that

coffee is a shade crop. Coffee trees require shade, and by intercepting raindrops forest

canopies protect soil from weathering. Furthermore, the roots of shade trees help stabilize

soils. In the early decades of the twentieth century so much of the highland forests had been

lost to tobacco and subsistence crop farming that in 1925 the Governor of Puerto Rico

encouraged coffee planting as an economical means of reforestation.91 His call was not

heeded. Coffee production declined after 1920, and many plantations were abandoned.

Although abandoned coffee plantations could be quickly overtaken by grass or forest, which

stabilized soils and reduced the potential for erosion, more often the owners cut shade trees

90 Annual Report of the Governor of Porto Rico, 1901, p. 22; Annual Report of the Governor of Porto Rico, 1921, p. 450, AGPR, Annual Reports. 91 Annual Report of the Governor of Porto Rico, 1925, p. 31, AGPR, Annual Reports.


www.whpress.co.uk for burning charcoal.92 So long as coffee remained profitable, forest cover that would be

felled for cultivating other cash crops was retained as forest.

But even as a shade crop, intensive coffee cultivation encouraged erosion. First, much

of the forest had to be cleared for plots of coffee trees, even if some forest cover was

retained. Most of the coffee planted between 1898 and 1934 required shade, but planters

discovered a variety that produced ten times the average yield when exposed to direct

sunlight.93 So some coffee planters did clear large forest areas. Planting in this manner

resulted in a high initial yield, but coffee plants exposed to direct sunlight died sooner,

encouraging planters to clear even more land. Second, coffee seedlings were often planted in

loose, unstable soil. Although some highland soils were deep and porous, coffee was often

planted in thin soils that could not absorb much water. Furthermore, in contrast to sugar,

coffee trees were planted during the rainy season (April through November). This meant that

soils were freshly tilled and especially vulnerable to erosion during the times of heaviest

rain.94 Third, intensive coffee cultivation drained the soil of its nutrients. Nutrients alone do

not stabilize soil, but they support microorganisms that do and thus the depletion of nutrients

makes soils more vulnerable to weathering. Coffee was planted most intensively in the Lago

Guayabal drainage basin between 1913 and 1920.95 Coffee cultivation declined after World

War One and then suffered further setbacks as a result of the hurricanes in 1928 and 1932 and

the Great Depression. Coffee had the lowest per hectare erosive potential of Puerto Rico’s

highland cash crops, but its cultivation covered a large share of Lago Guayabal’s watershed.96

Highland sugar cultivation had greater erosive potential than coffee, but it affected a

much smaller area. Between 1898 and 1934 most of the sugar grown in Puerto Rico was on

92 W.W. Pate, et al., ‘Reconnaissance Erosion Survey – Puerto Rico,’ 27, NARA II, RG 126, Series CF, Box 797. 93 Luis R. Soler-López, Sedimentation History of Lago Guayabal, 2001, p. 5. 94 Ibid. 95 Ibid. 96 For more on the environmental impact of the Puerto Rican coffee boom, see: Fernando Picó, ‘Deshumanización del trabajo y cosificación de la naturaleza: los comienzos del café en Utuado,’ Cuadernos de la Facultad de Humanidades 2 (1979): 55-70.


www.whpress.co.uk the fertile, irrigated lowlands. Cane was also grown in the highlands, but only on small

patches of land that were flat relative to the rest of the mountainous interior, but still steep by

lowland standards. Because the highland soils were often thin and relatively steep, the erosive

potential of highland sugar cultivation was high. In 1935 the Department of Agriculture’s

Soil Conservation Service carried out a soil erosion survey in Puerto Rico. Pate, the survey’s

chief soil scientist, noted that highland sugar, even on a gentler slope, provoked about three

times as much soil loss as coffee.97 Sugarcane plantations were uncommon in the

mountainous interior, but when it was cultivated in the highlands, as was the case in Lago

Guayabal’s watershed, sugar had a high erosive potential.

Lago Carite and Lago Patillas, the two other major reservoirs of the SCIP, fared much

better with regard to sediment accumulation than Lago Guayabal. Located on the eastern end

of the irrigation district, these dams were farther removed from the island’s coffee

production. During its lifespan the storage capacity of Lago Carite has been reduced by 26

percent, from 13.95 million cubic meters in 1913 to 10.74 million cubic meters in 1999.98

The storage capacity of Lago Patillas decreased from 17.64 million cubic meters in 1914 to

13.84 million cubic meters in 1997, a 21 percent loss.99

If these rates are not as high as Lago Guayabal’s, they are notable nonetheless and

were a concern to azucareros who had invested in these dams. Even at full capacity the

reservoirs could not quench the azucareros’ thirst and any additional loss as a result of

sedimentation caused alarm. In 1935 the drainage basin of Lago Carite was declared a forest

reserve in an attempt to reduce erosion.100 As was the case with Lago Guayabal, high annual

rains, hurricanes, and steep slopes all contributed to high erosion rates. But agricultural and

97 W.W. Pate, et al., ‘Reconnaissance Erosion Survey – Puerto Rico,’ 11, NARA II, RG 126, Series CF, Box 797. 98 Luis R Soler-López and Ramón A. Carrasquillo-Nieves, Sedimentation Survey of Lago Carite, Puerto Rico, Water Resources Investigations Report 00-4235, USGS, 1999. 99 Luis R Soler-López, Richard M.T. Webb, and Francisco Pérez-Blair, Sedimentation Survey of Lago Patillas, Puerto Rico, Water Resources Investigations Report 99-4030, USGS, 1997. 100 Luis R Soler-López and Ramón A. Carrasquillo-Nieves, Sedimentation Survey of Lago Carite, Puerto Rico, 1999.


www.whpress.co.uk land use also contributed to erosion and this was the only variable that could be controlled.

The forest reserve had a positive effect on slowing erosion even though it did not include all

land in the basin, and land clearing persisted in the watershed.101

The smallest dams of the project fared the worst. In 1968 engineers from the Bureau

of Reclamation concluded in a report on the Coamo Dam, the westernmost of the project’s

two smaller dams, that ‘reservoir silting and water hyacinth growth has all but eliminated

storage capacity of the reservoir.’102 In the 1990s the Coamo Dam became 100 percent filled

with sediment and it no longer retains water for distribution.103 In the second half of the

twentieth century the sugarcane industry declined relative to manufacturing in Puerto Rico,

which meant that azucareros needed less irrigation water. Sedimentation reduced the amount

of water that could be stored, but by the 1990s azucareros no longer needed it.

The sugar industry began its decline in the late-1950s, and in the following decades

the island’s centrales were abandoned and its canefields repurposed. The Great Depression

had called into question the island’s dependence on cane exports. The collapse in sugar prices

on the world market after 1930 and US sugar import quotas imposed in 1934 damaged the

Puerto Rican cane industry. In 1934 a group of government officials drafted what became

known as the Chardón Plan, which called for industrialization, economic diversification, and

redistribution of idle sugar lands to subsistence farmers.104 In the 1940s Governor Tugwell

launched ‘Operation Bootstrap,’ putting the Chardón Plan into place and inserting the first

nails into the coffin of Puerto Rico’s sugarcane industry.105 Industrialization took a few

decades to fully displace sugar plantations, but large sugar mills began closing in the 1960s

101 Ibid. 102 Harold E. Sheda and James Legas, Report on the Condition of Coamo Dam, Puerto Rico, Oct. 1968, Serie: Riego de Guayabal, AHAEE. 103 William Jobin, ‘The Caribbean Region,’ in William Jobin, (ed.) Sustainable Management for Dams and Water, (New York: Lewis Publishers, 1998), pp. 201-214. 104 Dietz, Economic History of Puerto Rico, pp. 149-154. 105 Ibid., pp. 149-54 and 206-212.


www.whpress.co.uk and 1970s and the last one, Central Aguirre, closed in 1991.106 At the same time demand for

irrigation water evaporated, urbanization increased the need for water in the south coast’s

towns and cities. By the end of the century the SCIP’s reservoirs became primarily

responsible for supplying not irrigation, but municipal water.

Sedimentation continued to be problematic for Puerto Rican reservoirs after the island

industrialized. Between 1950 and 1953 the Puerto Rican Government built Lago Loíza to

store water for growing metropolitan San Juan. Since the 1950s, Lago Loíza has lost almost

50 percent of its storage capacity because of sediment accumulation. Drought demonstrated

what this loss means for residents who depend on water from the reservoir. In May 2015 the

Puerto Rican government began rationing water in San Juan, and by August residents were to

go three out of every four days without fresh water.107 In July, the US Department of

Agriculture declared the municipalities of the former Irrigation District to under extreme

drought, and residents suffered dramatic water shortages, though rationing was less severe on

the south coast than in San Juan.108

Accelerated sedimentation is an important consideration for dam building projects in

the Caribbean. At best, high siltation rates increase the cost of building and maintaining

reservoirs, and, at worst, they threaten to make reservoirs undependable as long-term supplies

of fresh water. Dredging is an expensive solution, and Puerto Rico is in the throes of a major

debt crisis and recovering from Hurricane Maria. Even after industrialization, Puerto Rico

never gained the economic strength to absorb the long-term environmental costs of the

SCIP’s reservoirs. This paper highlighted an unexpected environmental legacy of US

imperialism, and it would be worthy of future scholarship to reflect on the ways in which the

106 César Ayala, ‘The Decline of the Plantation Economy and the Puerto Rican Migration of the 1950s,’ Latino Studies Journal 7 (1) 1996: 61-90. 107 Gloria Ruiz Kuilan, ‘Arranca el miércoles el racionamiento de agua,’ El Nuevo Día, San Juan, Puerto Rico, 11 May 2015; Sara del Valle Hernández, ‘Tres días de racionamiento para clientes del carraízo,’ El Nuevo Día, San Juan, Puerto Rico, 5 Aug. 2015. 108 Frances Rosario, ‘En sequía extrema Salinas y Guayama: se unen a otros cuatro municipios que están bajo esta misma categoría,’ El Nuevo Día, San Juan, Puerto Rico, 23 July 2015.


www.whpress.co.uk island’s political status has constrained its ability to ameliorate the short-term costs of

sedimentation and plan for more sustainable management of its freshwater resources.

Conclusion

The story of North American dam building is incomplete without the United States’

overseas colonies because the motivations and consequences of building dams in the

Caribbean were different than on the mainland. Imperial politics shaped the how the risks and

rewards of dam building in Puerto Rico were distributed. The SCIP was designed to water to

the cane plantations of large corporations from the mainland who reaped tremendous profits

from their cane exports while paying their Puerto Rican fieldworkers comparatively little. In

contrast to the dam building boom that was unfolding in the American West at the same time,

the SCIP was designed to reinforce established socioeconomic hierarchies, not change them.

The consequences of building dams in the US Caribbean territories were also

different than on the mainland. Large concrete dams were new to the Caribbean sugar

industry, making the irrigated south-eastern canefields an unprecedented undertaking in

Caribbean agriculture. Though the SCIP was one of thousands of such irrigation projects

undertaken around the world throughout the twentieth century, it was one of the earliest to be

undertaken with US engineering expertise and capital and in support of US imperial

interests.109 It was the first time that US engineers designed and built irrigation dams that had

to contend with a tropical climate and hurricanes, conditions that led to unforeseen

environmental consequences after construction.

The SCIP reengineered Puerto Rico’s rivers and turned the south-east into a giant

canefield, but it did not control nature as azucareros and engineers had envisioned. Seasonal

droughts continually reduced the amount of available water, though the incidental installation

109 For an overview of twentieth-century hydrosphere engineering see: J.R. McNeill, Something New Under the Sun: An Environmental History of the Twentieth-Century World (New York: W.W. Norton and Co., 2000), pp. 149-192.


www.whpress.co.uk of hydroelectric turbines provided cheap electricity for groundwater pumps that made up for

the loss. If the accidental bonanza of hydroelectricity worked to the project’s benefit, other

unanticipated developments did not. Reservoirs became repositories for silt from upstream

watersheds, where the combination of steep topography, loose soils, and severe weather

accelerated erosion and greatly increasing the amounts of sediments to the reservoirs. Rapid

siltation, in turn, further curtailed already scarce water supplies and threatened to make the

dams obsolete. Sediments continued to build even after the sugar boom ended, an enduring

legacy of US imperialism that is expensive to mitigate.

Documents

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