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At 750 million gallons a day, Puerto Ricos water consumption is already near the maximum limits, taxing water resources and presenting a huge challenge to planners.
By JOHN MCPHAUL
December 2, 2004
Water supply is the problem
When it comes to a reliable water supply, management incompetence at Prasa may not be the islands biggest problem.
Puerto Rico could well be running out of potable water. While the public perennially points to the management of the Puerto Rico Aqueduct & Sewer Authority (Prasa), whether in government or private hands, for the chronic water problems throughout the island, little attention is paid to the availability of water resources.
With the growing demand for water, the island could be coming very close to tapping out its capacity to produce potable water, making it imperative to seek alternatives, according to experts.
"The situation of water resources on the island, while not yet critical, is serious, especially in the aquifers, which are all seriously stressed," said Ferdinand Quiñones, director of the Office of the Water Plan at the Department of Natural & Environmental Resources.
Two years ago, Quiñones office began working to create a comprehensive database of the water resources available in Puerto Rico. The database will result in the publication of a water atlas for the island, which should be finished by years end.
Quiñones said about two billion gallons of water flow through Puerto Ricos rivers and streams every day. His offices study, which is 90% to 95% complete, shows that residential, business, and industrial water use in Puerto Rico amounts to 750 million gallons of water a day.
That figure is perilously close to the maximum safe-use, the amount of water available for use from the islands aquifers, streams, and reservoirs without adversely affecting the environment under drought conditions, according to the U.S. Geological Survey (USGS).
For instance, during the drought of 1994, which led to rationing and eventually to the construction of the 100-gallon-a-day superaqueduct, the Sergio Cuevas water-filtration plant, which provides drinking water to San Juan, exceeded the safe-use capacity of its source, Lake Carraizo. Each river, reservoir, and aquifer has its own safe-use capacity, for a total 750-million-gallon-a-day capacity for the whole island. "During a drought, water-filtration plants have to borrow water from nearby jurisdictions, and the systems could collapse during a prolonged drought," said Fernando Gomez, a hydrologist with the USGS.
"If we had a serious drought now, we would have just enough water [in rivers and reservoirs] to supply the islands needs," said Quiñones. "But if we had a drought as serious as the one in 1994, we would have severe shortages."
Gomez noted that the yearlong drought in 1994 caused a shortage in the San Juan metro area of some 85 million gallons of water a day. A three-year event like the one in the 1880s would cause a considerably larger shortage.
According to Gomez, Prasas daily consumption of water between 1995 and 2000 jumped by 100 million gallons a day, or around 18%. Though that increase coincided with a sizable increase in infrastructure that appreciably improved the capture and distribution of water, the likely possibility of a similar increase in demand will take the island well beyond the safe-use limit.
Fixing the leaks
Quiñones said the first strategy to increase the volume of water available for delivery to Prasa customers is to fix the leaks responsible for the loss of 40% to 50% of the water treated at Prasa plants. The authority has consistently listed fixing the leaks as one of its priorities. Yet whether Prasa has been under private management or public management, the leaks have never been fixed.
Several years ago, amid much fanfare, the privately run Puerto Rico Water Co. brought in Mexican consultants who used radar to locate leaks. Two years later, the Puerto Rico Water Co. was history. Its successor, Ondeo, lasted two yearswith no appreciable progress in fixing the leaks. Back again in government hands, Prasa is once more touting fixing leaks as a priority.
The authority is developing a strategy to deal with the leakage, including creating an office dedicated to water-loss control. "Its an office whose only job is an islandwide effort to reduce leaks," said Quiñones.
Also under government management, the authority has been divided into five regions, which makes the administration of one of the largest water utilities in the U.S. more fluid, said Prasa Executive President Jorge Rodriguez. "We are operating under a new, much broader vision, which will put all tools at our disposal," he said. Prasa is assigning permanent crews whose only job is to detect and repair leaks and is developing a capital investment program to replace sections of pipe that leak beyond repair.
Quiñones said the program could cost hundreds of millions of dollars. Boston spent $5 billion to reduce leakage in its water-delivery system from 45% to 25%. Quiñones said he is optimistic about the success of Prasas plan, which will be carried out under Executive Director for Infrastructure Jose Ortiz.
A plan for the future
Quiñones said the water plan includes recommendations on how to manage the islands aquifers, which are stressed by the removal of more water than is replenished.
In the southern region, the recommendation is for no new removal of water from the Santa Isabel-Coamo aquifer. The intrusion of saltwater from the ocean, sucked in by the removal of fresh water, is rapidly depleting the resource. The plan also recommends consideration of a proposal to recharge the aquifer using effluent from the Santa Isabel wastewater-treatment plant, which currently discharges water into a creek that quickly runs off into the ocean.
The plan also recommends no further withdrawals from the upper alluvial aquifer, the body of water at superficial levels beneath the surface, in the northern coastal area, which is also suffering from overpumping of some 50 million gallons of water a day. The wells that pump some 14 million gallons of water a day from the deep-running artesian wells on the north coast are leaking, so the recommendation is to stop pumping until the leaks are fixed.
Prasa is planning to build a plant in Dorado with the capacity to treat 10 million gallons of wastewater a day, and the plan suggests using this water to recharge the north-coast aquifer. The water-resource study indicates the interior alluvial aquifers in Caguas-Juncos, Ciales, and Cayey are being pumped to the maximum, said Quiñones.
Prasa takes 68% of the water it uses to produce potable water from the islands reservoirs, said Quiñones. "The reservoirs are absolutely critical," he said. The water plan proposes the drafting of a management plan for each reservoir. "They have to take a look at all the data in a given area to reduce erosion, ensure water quality, and make reforestation plans," said Quiñones. The plan also recommends the creation of Hydrographic Basin Councils made up of local residents and others involved in the restoration of the basins.
Former Prasa Executive President Emilio Colon, currently with the U.S. Army Corps of Engineers, said that even if Puerto Rico is reaching safe-use limits, the water resources could be managed in other ways to provide for the islands potable-water needs. For instance, the islands six coastal wastewater-treatment plants pump about 200 million gallons of water a day into the ocean. Though it isnt possible to use that water as a potable-water source per se, it could be pumped back upstream to increase the volume and safe-use margin of the river.
"You could recharge the rivers, increase the volume of water sufficiently to sustain the river ecologies and still draw water as a potable source," said Colon. Recharging the aquifers with treated wastewater also would forestall their gradual salinization.
To accomplish that, however, the wastewater-treatment plants would have to be upgraded to secondary treatment. The plants currently provide only primary treatment, which consists of treating water with chlorine before discharging it into the ocean. Secondary treatment adds the step of oxygenating the wastewater, usually by filtering it though a bacterial culture.
The U.S. Environmental Protection Agency has issued 301-h waivers to five of the six plants that discharge primary-treated water into the ocean. The waivers are necessary because the federal Clean Water Act permits only the discharge of secondary-treated water into bodies of water. Upgrading the plants to secondary treatment would cost hundreds of millions of dollars. Under the conditions of the 301-h waivers, however, the plants must be upgraded to secondary treatment within 15 years.
The dredging option
Another option would be to dredge existing reservoirs to expand their capacity, said Colon. Gomez of the USGS said, however, that dredging reservoirs is a losing battle against nature. The dredging of Lake Carraizo in 1997, accomplished at a cost of $60 million, increased the capacity of San Juans principal source of water. A recent USGS bathymetric study of the contours of the reservoirs bottom, however, showed that about half of that capacity has been lost to renewed siltation, an inevitable consequence of erosion, said Gomez.
Still, management of the existing water resources and infrastructure would forestall having to choose from other impractical options, said Colon. Desalinization is too expensive, and building more reservoirs would raise environmental concerns. Blocking rivers and inundating upstream river environments has been unpopular with environmentalists for years and has become increasingly unpopular even among government agencies, said Colon. He said the trend in the States is to dismantle reservoirs to restore river environments.
While the USGS has scouted out a number of possible dam sites, Colon said he thinks building another reservoir on rivers would be impractical. "The USGS sister agencies [the U.S. Fish & Wildlife Service and the U.S. Environmental Protection Agency] would be the first to raise objections," he said.
More reservoirs needed
Prasa is planning, however, to build off-stream reservoirs, where water is taken off rivers and stored in reservoirs away from the rivers themselves. This poses less of an environmental concern because water can be drawn during rain so as not to appreciably reduce the river-runoff rate. Also, reservoirs dont engulf the upstream river environment.
Reservoirs to be built in this manner include one on the Blanco River to contain 12 million gallons, for which plans have been finalized, and a 12-million-gallon reservoir on the Beatrice River in Caguas, for which an environmental impact statement has been submitted. A 15-million-gallon reservoir on the Valenciano River in Juncos is on the drawing board, as is a 12-million-gallon reservoir on the Fajardo River. A 60-million-gallon reservoir on the Casei River in the Añasco River Basin is about 10 years away, said Quiñones.
Potential reservoir sites identified by the USGS include the Cavonillas River, where 25 million gallons of water a day could supply the San Juan metro area. In Caguas, two potential dam sites on the Quebradillas River could provide five million gallons of water a day to the Caguas filtration plant, in addition to the Beatrice River reservoir previously mentioned. In Comerio, a second reservoir on the La Plata River would create 50,000 acre-feet of storage that would provide 65 million gallons of water a day.
In Mayaguez, three potential dam sites have been identified. A 16,000-acre-foot reservoir on the Rosario River in Sabana Grande would provide 20 million gallons of water a day. A reservoir on the Yaguez River would provide seven million gallons daily, and a reservoir on the Caña River would provide eight million gallons of water a day.
"We have plenty of water; we just need a place to store it," said Quiñones.
Another concern is the condition of the islands watersheds, where development is causing siltation, which could diminish the reservoirs capacities. Rodriguez said he plans to work closely with the Puerto Rico Conservation Trust to acquire land in watersheds to better protect rivers and reservoirs.
One particularly stressed area of the island is the eastern end, where Prasa is having a hard time keeping up with rapid construction development. Community groups and environmentalists have complained the region is already suffering from chronic water shortages.
Prasas Rodriguez said the Northeastern Aqueduct, which entails building a reservoir off the course of the Fajardo River that will provide 12 million gallons of water daily, will provide more than enough water to supply the growing development needs, including the water for the San Miguel-Four Seasons and Dos Mares-J.W. Marriott resorts in Luquillo.
Environmentalists have gone to court to try to block the construction of the resorts, both of which will be built partially on land sold to the developers by the Puerto Rico Industrial Development Co. They argue the Fajardo River reservoir will provide only five million additional gallons of water a day, with the river currently providing seven million gallons a day. The additional five million gallons wont satisfy the needs of the growing population in the area, say environmentalists.
According to the USGS, Luquillo is at the bottom of the list of municipalities in terms of gallons of water a day provided by Prasa. In the San Juan metro area, Prasa provides 150 gallons of water a day per person; in Luquillo, it provides only 75 million daily per person. The total 12 million gallons a day allowed with the new damn wouldnt be enough given the scope of planned development in the region, according to the critics.
Quiñones, however, doesnt agree. For the municipalities of Ceiba, Fajardo, and Luquillo, Prasa currently provides 12.6 million gallons of water a day. With the addition of the five million gallons daily from the Fajardo River reservoir, Prasa will have sufficient water to provide for the areas 80,000 residents plus the projected population growth.
"If the population grows, theres still plenty of water," he said.
Gubernatorial candidates would focus on infrastructure to solve water woes
The next governor of Puerto Rico will undertake an ambitious infrastructure project to correct the islands perennially deficient water system. Though we still dont know which will be the next governor, both Popular Democratic Party candidate Anibal Acevedo Vila and New Progressive Party candidate Pedro Rossello have promised to address the islands water problems by making large investments in infrastructure.
Acevedo Vila has promised to institute an Agua Segura (Safe & Reliable Water) project with the investment of $1.6 billion in infrastructure projects. During his political campaign, Acevedo Vila told CARIBBEAN BUSINESS there would be a provision or financing mechanism to ensure the money is used exclusively for the infrastructure projects.
Rossello said during his campaign that he would resolve the problems posed by the hundreds of different water systems around the island by building seven more superaqueducts under a project called Agua por un Tubo y Siete Llaves (Water Through One Pipe & Seven Faucets). The program would also regionalize the water system.
One water expert who spoke to CARIBBEAN BUSINESS on condition of anonymity said the large infrastructure projects may be good for contractors and businesses that sell pipe, but moving water around wont solve the basic problem of diminishing safe-use capacity. Other means such as building more reservoirs or desalinization must be considered.
Following experiment with private management, Prasa has big plans
Since the Puerto Rico Aqueduct & Sewer Authority (Prasa) ended an eight-year experiment with privatized management in May, the new management has embarked on a five-year plan to invest $1.9 billion in new infrastructure at the much-criticized authority.
Prasa Executive President Jorge Rodriguez predicts the new initiatives will make for a historic change in the operations of the authority. But first, Prasa has to overcome the disorder and uncertainty left after eight years of private management and the continuing strike by its principal union, the Authentic Independent Union.
The private-management experiment began in September 1995, when the Rossello administration contracted France-based Compagnie Generale de Eaux to run Prasa. Claiming that its contract was too restrictive to allow it to improve the islands water problems, the company saw its contract renegotiated once before it expired and wasnt renewed in 2002. Instead, the Calderon administration awarded France-based Ondeo a $3.82 billion, 10-year management contract.
The government reasoned that only a long-term contract would allow the private company to make the investments needed to put Prasa on the right track. But after less than two years, Ondeo was already asking for an additional $93 million, saying it had been given bad information about the conditions of the authority before making its original bid for the contract.
The Calderon administration responded by canceling the contract and announcing the government would again assume Prasas management. The government officially took over management of Prasa on May 1, 2004.
Rodriguez said the government is in a better position to manage the utility because private companies, with an eye on the bottom line, skimp by failing to invest in maintenance, letting equipment decay and causing breakdowns. Private companies also have less of an incentive to think in the long term. "We are devising integral strategic plans for five, 10, 20, and 25 years," said Rodriguez.
The authority is beginning by dividing the island into five regions to create systems that are of a more manageable size than the sprawling islandwide system, which is really more like some 200 small systems jumbled together. "Were going to have more regional plants, more simple plants. Were also going to try to unite the networks within regions as much as possible," said Rodriguez.
Each region will have its own hierarchy, added Rodriguez. "There will be more delegation of authority to the chiefs of operations," he said.
The authority also has on tap a $1.9 billion infrastructure plan that includes an 18-million-gallon reservoir on the Blanco River, a 60-million-gallon reservoir near Mayaguez, a regional wastewater-treatment plant in Dorado, and a regional treatment plant in Caguas that will take wastewater from Caguas, San Lorenzo, Juncos, Aguas Buenas, and Gurabo. Wastewater-treatment plants are also planned for Santa Isabel, Vega Baja, Ponce, Guayama, and Jayuya, said Rodriguez.
301-h waiver: The federal Clean Water Act requires that all wastewater-treatment plants that discharge into any bodies of water must use secondary treatment. This requirement can be waived with the issue of a 301-h waiver if the plant that discharges into the ocean can produce wastewater with primary treatment that meets Clean Water Act requirements after passing through a so-called mixing zone. The mixing zone, of a predetermined surface area, serves as a filter. The water must meet the requirements by the time it reaches the edge of the mixing zone. Five plants in Puerto Ricoin Carolina, Arecibo, Aguadilla, Puerto Nuevo, and Bayamonhave received 301-h waivers. A decision on the Ponce plant is pending.
Alluvial aquifer: An aquifer is a body of water beneath the earths surface. An alluvial aquifer is water at a shallow depth below the earths surface that has run off after rains and seeped into the ground.
Artesian aquifer: Water that is deeper below the earths surface than an alluvial aquifer and beneath a layer of impermeable material. Artesian wells are drilled through the impermeable layer to gain access to the water.
Bathymetric: The measurement of depth at various places in a body of water.
Erosion: When it rains, water running off land, especially land that has been deforested, will carry with it part of the topsoil.
Primary treatment: The treatment of wastewater at sewage-disposal plants by removing solids and adding chlorine. Polymers can also be added for more efficient removal of solids in advanced primary treatment.
Safe-use: The amount of water that can be safely used for drinking without adversely affecting the environment during times of drought. Some two billion gallons of water a day flow through Puerto Ricos rivers, but it is judged safe to use only around 750 million gallons of those. The safe-use capacity can be increased by building new reservoirs or by recharging rivers with treated wastewater now being discharged directly into the ocean.
Secondary treatment: The treatment of wastewater by using primary treatment, followed by the filtration of water through a bacterial culture. The bacteria feed on the nutrients in the wastewater. The process produces wastewater that purifies the water to a greater degree than primary treatment.
Siltation: Once topsoil eroded from the land reaches a body of water, it typically becomes suspended in a murky silt. The resulting suspension is siltation.
This Caribbean Business article appears courtesy of Casiano Communications.