WINTER Wastewater Master Plan for Cartagena HORIZONS. water environment solutions. The. Averting Damage to Vital Infrastructure

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1 WINTER Trenchless 6 Analyzing 8 Protecting Assets 13 Underwater Shrinking from Climate Change Construction Demand Ramifi cations Wastewater Master Plan for Cartagena HORIZONS water environment solutions The Averting Damage to Vital Infrastructure

2 Trenchless Construction in an International Access Channel In response to a Consent Decree, a complex $67.4-million utility relocation project in the access channels to the Port of Miami was completed both on-time and within budget. The Port of Miami is the second largest economic generator in Miami-Dade County and, as a result, recently signed a Memorandum of Understanding with the Panama Canal Authority to promote new business growth via the all water route between Asia and North America s East Coast through the expanded Panama Canal. The Port of Miami Improvements Program, which consists of various projects (including the utility relocation, a dredging operation, and a traffic tunnel), is anticipated to greatly enhance the local economy, maximizing utilization of port property while improving access for ships, commercial trucks, personal vehicles, and rail cars. As part of the program, Hazen and Sawyer recently provided fast-track design-build services to replace underwater pipelines to prepare for the dredging of the Port of Miami access channels to accommodate New Panamax ships allowed by the deepened Panama Canal. The Port of Miami was the only port south of Norfolk, VA., capable of being deep-dredged by This is the largest designbuild project the Miami-Dade County Water and Sewer Department (MDWASD) has undertaken and the first to be completed under the federal and state Consent Decree to upgrade the County sewer system. The 20-inch water main provides potable water service to the Port of Miami, Fisher Island, and Virginia Key, from two directions and is critical to the cruise ship industry since the ships take on water from the Port for distribution to the Caribbean Islands. 2 HORIZONS WINTER 2014

3 The force main replacement was completed via a 72-inch diameter micro-tunnel from Fisher Island to an in-water shaft south of Miami Beach. The 1,100-foot long micro-tunnel, installed at a depth of 80 feet carries a new 60-inch fiberglass-reinforced pipe. The water main replacement was completed via a 140-foot deep and 1,600-foot long 24-inch diameter Horizontal Directional Drill from the Port of Miami to Fisher Island to replace an existing 20-inch water main. Government Cut Utility Relocation Projects The Government Cut Utility Relocation Projects consist of the replacement of a critical 30-year old, 54-inch collection system sewage force main, and a 20-inch water main below the shipping channels of the Port of Miami via the design-build approach. Ric-Man Construction led the construction team; Hazen and Sawyer led the design team. The primary driver of the design was the installation method. A trenchless method was selected to minimize the environmental impacts and also to allow for deeper installation beneath the seabed to enable dredging of the shipping channel in the Port of Miami to accommodate the deeper draft vessels traveling through the Panama Canal. 24-inch Water Main Installation Horizontal Directional Drilling MDWASD owns, operates, and maintains a 20-inch diameter ductile iron loop from the City of Miami to the Port of Miami, Fisher Island, Virginia Key, and back to the City of Miami. The main provides potable water service to the Port of Miami, Fisher Island, and Virginia Key from two directions and HORIZONS WINTER

4 and laid along the edge of the Fisher Island golf course. The pullback was coordinated with Fisher Island officials in order to not interrupt their commercial ferry access. Once the HDPE pipe was pulled through, approximately 500 feet of 24-inch ductile iron pipe was installed and connected to the existing 20-inch water main via two hot taps. This approach minimized the potential for water service interruptions while the connections were made. Coordination with the Port of Miami was critical to minimize impacts to operations and other improvement projects. In addition, all of the environmental resource and coastal construction permits were fast-tracked in order to maintain the project schedule. Due to the fast-tracked permits, this portion of the project was completed on budget and six months ahead of schedule. DR11 HDPE with PE 4710 resin was selected as the pipe material due to its inherent ability to withstand higher tension loads. is critical to the cruise ship industry, since the ships take on water from the Port for distribution to the Caribbean Islands. The water main replacement was originally proposed to be installed via an 850-foot long, 60-inch diameter microtunnel across Fisherman s Channel (between the Port of Miami and Fisher Island). However, in an effort to minimize project risks, reduce costs, minimize environmental impacts, expedite the schedule, and cause minimal disruption to the community, the design-build team completed the installation via a 140-foot deep and 1,600-foot long 24-inch diameter horizontal directional drill (HDD). Several material options were considered for the HDD installation. Steel was not implemented into the design due to cost, high susceptibility to corrosion in a salt water environment, and additional QA/QC time required for analyzing and testing of welded joints. After careful consideration, DR11 HDPE with PE 4710 resin was selected as the pipe material due to its inherent ability to withstand higher tension loads and greater service life. The first step to installing the pipeline was to drill an 8-inch pilot hole from the Port of Miami to Fisher Island using a 550 ton drilling rig. Once the pilot hole was established, the bore hole was increased via a two-pass reaming process, first with a 26-inch reamer and later to its final size with a 42-inch reamer. After the reaming process was completed, the 24-inch HDPE pipe was pulled from Fisher Island to the Port of Miami. All 1,600 feet of pipe had already been fused 60-inch Force Main Installation Micro-Tunneling The MDWASD also owns, operates, and maintains a 54-inch diameter pre-stressed concrete cylinder pipe (PCCP) force main that transmits wastewater from the City of Miami Beach (and from communities further north including Surfside, Bal Harbour, Bay Harbor Islands, and North Bay Village), under Government Cut, across Fisher Island, and under Norris Cut to the 143-mgd Central District Wastewater Treatment Plant (CDWWTP) at Virginia Key. The pipe does not have redundancy and could not be taken out of service. The force main replacement was completed via a 72- inch diameter micro-tunnel from Fisher Island to an in-water shaft south of Miami Beach. The 1,100-foot long microtunnel, installed at a depth of 80 feet, carries a new 60-inch fiberglass-reinforced pipe. For the installation of the force main, a launch shaft was designed at Fisher Island and a retrieval shaft was designed in the shallow waters at the edge of the Government Cut shipping channel. The launch and retrieval shafts were constructed by the secant pile method where drilled concrete shafts overlap to form cut-off walls. Each shaft included a bolted-together corrugated metal piping liner grouted inside the shaft to ensure the structure was water tight. The selected micro-tunnel boring machine allowed for a significant reduction in the retrieval shaft diameter, thus reducing the risk of water intrusion, as well as reducing environmental impacts and construction costs. A large coral relocation and mitigation program was also completed to protect and preserve benthic communities and coral species thriving in the Biscayne Bay. 4 HORIZONS WINTER 2014

5 The 13-foot and 20-foot diameter secant pile wall shaft designs featured four built-in unique water tightness features an external grout column, a secant pile shaft structure, a grouted annulus, and a steel can liner - all working together to form a 100-foot deep water tight structure. During construction, an inspection of the condition of the existing 54-inch force main found several defective segments between the in-water retrieval shaft and the City of Miami Beach force main that discharges into the MDWASD pipeline. As a result, the design-build team installed a second 700-foot long, 60-foot deep, 72-inch micro-tunnel from a new launch shaft in Miami Beach to the in-water retrieval shaft to replace the defective pipe segment. Project Completion Construction began in April 2011 and installation of both pipelines was completed by September 2013 in time for the commencement of the dredging project at the Port of Miami, which will bring the depth of the shipping channels from (-) 42 feet to (-) 50 feet. Work was completed without interrupting services to the residents in the coastal and northern Miami-Dade County areas. I m proud of our team at the Water and Sewer Department for bringing this complex, high-stakes project in on time and within budget, said Miami The design-build team installed a second 700-foot long, 60-foot deep 72-inch micro-tunnel from a new launch shaft in Miami Beach to the in-water retrieval shaft to replace a defective pipe segment. Mayor Carlos A. Gimenez. This is a great example of government getting the job done the right way, and it sets a high standard for the many projects that we will be embarking on as we overhaul our massive water and sewer system in the years ahead. The existing water main was relocated to 140' below sea level to accommodate new, larger ships coming into the Port through the deepened Panama Canal. Pre-existing 20" water main: 55' below sea level Relocated water main: 140' below sea level Larger ship profile enabled by Panama Canal dredging Existing ship profile HORIZONS WINTER

6 Understanding Demand in a Growing Desert Community As a large and growing desert community that shares sensitive water supplies with other cities, the City of Phoenix (AZ) must closely monitor water demand trends to ensure supply reliability. Hazen and Sawyer performed a comprehensive analysis of demand patterns for the City, which identified key influences on long-term water efficiency and conservation potential in order to improve the City s long-term planning policies. Total Water Consumption Per Account 0.6 Million Gallons per Account / Year % decrease in average water use per load (due to high efficiency washers) 24% decrease in average water per flush (due to low flow technology) HORIZONS WINTER 2014

7 20.2% decrease in water consumption per account Our research revealed that even as the number of user accounts continues to rise, overall demand is decreasing due to a variety of factors including improved plumbing efficiency, larger homes with less room for pools and landscaping, and high vacancy rates in multi-unit and commercial properties. Our analyses of demand factors revealed that 60-70% of water demand in the summer months is intended for non-critical outdoor purposes, providing opportunities for conservation in times of need HORIZONS WINTER

8 With significant portions of wastewater infrastructure located in coastal and flood-prone areas, municipalities must take proactive measures to fortify their assets. Protecting Assets from Climate Change Ramifications Hazen and Sawyer, as part of a joint venture, identifi ed and quantifi ed the impacts of climate change and population growth on New York City s sewer, drainage, and wastewater systems, and recommended adaptation strategies to manage risks. Two devastating recent storms - Irene and Sandy - demonstrated the risk to lives and property that coastal communities face as our climate becomes more volatile. As a denselypopulated coastal city, New York City faces significant challenges with respect to wastewater treatment and collection infrastructure. Most of the treatment plants and pump stations are located in low-lying, coastal areas particularly affected by and prone to flooding. The City turned to a team that included Hazen and Sawyer to help them proactively prepare to minimize the impacts of global climate change, including rising sea levels, increasing storm frequency and intensity, and elevated surface temperatures. In October 2013, the New York City Department of Environmental Protection (DEP) released the NYC Wastewater Resiliency Plan, the nation s most detailed and comprehensive assessment of the risk climate change poses to a 8 HORIZONS WINTER 2014

9 wastewater collection and treatment system. This long-term adaptation and optimization strategy, based on defined deterministic metrics, will ensure that the City s infrastructure will be robust enough to withstand predicted climate change scenarios. The ground-breaking study, initiated in 2011 and expanded after Superstorm Sandy, was based on an asset-by-asset analysis of the risks from storm surge at all 14 treatment plants and 58 pumping stations. If no action is taken, it is estimated that damage to the equipment from repeated coastal flooding at projected sea levels could exceed $2 billion over the next 50 years. The analysis recommends $315 million in costeffective upgrades at these facilities to protect valuable equipment and minimize disruptions to critical services during future storms. New York City s waterways are one of our greatest assets and we have invested well over $10 billion during the last decade to make our harbor cleaner than it has been in a century, said DEP Commissioner Carter Strickland. We are committed to ensuring that our wastewater infrastructure is resilient and can stand up to the rising sea levels and extreme weather events associated with climate change in order to limit future disruptions to the system. The City operates 7,500 miles of sewers, 96 pumping stations, and 14 wastewater treatment plants that employ advanced biological and chemical processes to treat more than 1.3 billion gallons of wastewater every day. Superstorm Sandy s storm surge inundated many of the facilities with sea water that damaged pumps and electrical equipment. Damage caused to the facilities also resulted in more Like the many at-risk wastewater treatment facilities shown in the map of New York City, the Hunts Point plant resides well within the 100-year flood zones, and is particularly vulnerable to surge. In all, the study found that all 14 wastewater treatment plants and 58 of the 96 pumping stations in New York City are at risk from future, large surge events. HORIZONS WINTER

10 The Oakwood Beach WWTP in Staten Island, NY, experienced a record 10 foot storm surge in the wake of Superstorm Sandy. Ten of the City s 14 treatment plants, and 42 of the City s 96 pumping stations, were damaged during Sandy. than 560 million gallons of dilute, untreated sewage were released into local waterways. While the City worked continuously before, during, and after the storm to protect equipment where possible, it became evident that additional protection would be needed for future extreme storm events. In total, 10 of the City s 14 treatment plants, and 42 of the City s 96 pumping stations, were damaged during Sandy and nearly $50 million has been already been spent on repairs. When completed, the City estimates that the immediate damages from Sandy will top $100 million. However, flooding risk is likely to increase as climate change results in rising sea levels and more intense storms. The entire analysis, from the initial mobilization and site visits to the final protective measure recommendation analysis, took just 6 months. During that span, detailed facility-specific reports were produced, providing the City with the rapid documentation needed to strategically rebuild and improve resiliency. Three Step Process The New York City Wastewater Resiliency Plan presents an assessment of the facilities identified as at-risk for flooding, potential costs of future damages, and suggested site-specific protective measures, such as elevating and water proofing critical equipment to reduce the risk of damage and loss of services. The Plan represents the culmination of a detailed and innovative risk assessment with three main components. 1. First, the Climate Analysis identified possible future rainfall, storm surge, sea level, and temperature scenarios to establish future conditions the City must prepare for. 2. During the Vulnerability Analysis, Hazen and Sawyer interviewed plant staff and performed walk-throughs of each wastewater treatment plant, identifying site-specific flood pathways, at-risk facilities, and at-risk assets in the 100-year flood with sea level rise. 10 HORIZONS WINTER 2014

11 Experts were mobilized from across the nation to visually inspect more than 500 buildings and close to 50,000 assets. Assessing protective measures involved detailed cost estimates, risk calculations, and coordination with operational staff. Careful and nuanced understanding of facility equipment, tunnel systems, pipe systems, and electrical conduits was needed to ensure appropriate recommendations. Ultimately, Hazen and Sawyer quantified the value of at-risk infrastructure in nearly 500 buildings. 3. Finally, a comprehensive Adaptation Analysis of various robust protective measures yielded a recommended path forward for hardening the City s wastewater infrastructure and reducing the likelihood of prolonged service interruption. For each at-risk location, Hazen and Sawyer selected optimal, site-specific protective measures using an innovative, risk-based cost-benefit analysis, while the JV partner performed a similar analysis for at-risk pumping stations. The Federal Emergency Management Agency s new advisory base fl ood elevation maps for a 100-year fl ood event were selected as the baseline for the analysis. An additional 30 inches of fl ooding was added to this baseline to account for expected sea level rise by the 2050s, the high end of projections from the New York City Panel on Climate Change. Flood pathways at each facility and the location of critical equipment were then compared to the anticipated fl ood elevation level to determine which infrastructure is potentially at risk. In determining the appropriate resiliency measures and the level of acceptable costs, DEP considered the value of each asset at wastewater treatment plants and pump stations, the population and critical facilities they serve, and potential impacts on nearby beaches and waterways. Cost-effective protective measures such as elevating equipment, water proofi ng buildings, and replacing traditional pumps with submersible pumps were then selected based upon cost and level of risk reduction. The result is a portfolio of strategies that will be implemented as part of future capital projects or as other funding mechanisms are identifi ed. The City will coordinate this work with broader coastal protection initiatives, such as engineered barriers and wetlands. The joint venture team collaborated with City planners, engineers, and operations staff at the earliest possible stages to maximize value across the City s missions and ensure immediate integration of climate change adaptation. At two facilities already in the midst of upgrades, the Manhattan and Gowanus Pump Stations, DEP has already incorporated a number of the study s recommended resiliency measures into ongoing work. DEP is installing a mechanical fl ood gate at the Gowanus Pump Station building, raising the control room fl oor and its critical electrical equipment, constructing a dike wall, and adding a waterproof membrane to the building s exterior. The DEP Plan, published in October 2013, is a public document which contains detailed information regarding future surge conditions, the methodology of the study, and facilityspecific vulnerability and adaptation measures. Future Applications and Implications The study, the fi rst to assess coastal fl ooding risks based on fi ne resolution maps and a detailed analysis of the elevation of individual components of the wastewater system, will serve as a national model. In addition, the NYC Wastewater Resiliency Plan will provide the basis for requests to the federal government to fund resiliency measures. The Plan serves as valuable informational resource for operators, planners, and engineers for use in strengthening emergency preparedness and better integrating proactive and informed protective measures in future designs. The analysis pinpointed facility vulnerabilities and high-risk infrastructure, arming DEP with the information needed to prioritize and systematically implement HORIZONS WINTER

12 resiliency upgrades. In addition, the plant vulnerabilities and lessons learned from Superstorm Sandy were synthesized in plant-specifi c reports and reference sheets. This transfer of operational knowledge is critical for effective preparation for future extreme surges. For example, operators can scan the reports or guidance sheets before a storm surge event hits, comparing facility and equipment elevations with the anticipated fl ood levels to rapidly identify key areas requiring protection. The Adaptation Analysis produced a set of forward-looking resiliency initiatives and new, comprehensive design recommendations that account for more severe surge conditions. Furthermore, a user-friendly and streamlined reference of all wastewater infrastructure containing details such as level of risk, vulnerable flood pathways, and recommended courses of action will help future engineers integrate knowledge of facility vulnerabilities and site-specific protective measures into future system upgrades and facility designs. Disseminating information to other City government offices, other coastal municipalities, and the public was a key educational component of the project, with the goal of continuing the movement towards greater proactive flood resiliency. New York City has demonstrated exceptional leadership in gathering community leaders to move forward on adapting and enhancing resilience to the substantial risks posed by climate change, said Daniel Kreeger, Executive Director of the Association of Climate Change Officers. The latest product of these efforts, the NYC Wastewater Resiliency Plan, is a model for local, state, and federal government officials nationwide. The high-profile nature of the project established NYCDEP at the forefront of proactive climate risk management, and demonstrates the feasibility and value of performing risk assessments. The study shows that a detailed risk assessment can be rapidly executed and provides invaluable information regarding proactive protection measures that could save a municipality millions of dollars in damage repairs. The study serves as a model for other coastal cities around the globe that can use the adaptable risk management framework to perform their own assessments, building stronger, more resilient communities against future climate risks. Investing $315 Million in strategic fortification can safeguard $1.1 Billion of vital infrastructure and can save the City $2.5 Billion in emergency response costs over the next 50 years. 12 HORIZONS WINTER 2014

13 The waterways of Cartagena, Colombia, one of the most heavily used ports in the Caribbean Sea, were being degraded by releases of untreated wastewater, one of several factors that prompted the establishment of a wastewater master plan. The population of Cartagena (Colombia) has experienced explosive growth within the last 40 years, but expansion and improvements to infrastructure have not kept pace. Hazen and Sawyer worked to upgrade wastewater infrastructure to protect public health and a substantial tourism industry, realizing a nearly immediate improvement in surrounding water quality. Assuring a Viable Future for a HISTORIC CITY Founded in the 1500s by the Spanish as the main port for its famed galleons to carry gold, silver, and jewels to the New World, Cartagena de Indias (Cartagena) today has a population of nearly one million residents and a substantial tourism industry. Tourist income, which has become the mainstay of the local economy, was becoming increasingly threatened by the discharge of all wastewaters to the local estuary (Ciénaga de la Virgen) and bay (Bahía de Cartagena) through outfalls, force mains, and open sewers without treatment. The Bahia is one of the most heavily used ports in the Caribbean Sea, with more than HORIZONS WINTER

14 28 million tons of cargo handled on an annual basis. Industrial development has been encouraged to support the local economy and now more than 80 industries are situated along the Bahía de Cartagena s eastern shoreline. Passenger cruise ships have also adopted Cartagena as a regular port of call. The historical importance of the City, combined with the Colombian government instituting effluent discharge standards in Decree 1594 and an increased need for sustainable development, prompted the local government to pursue the advancement of a master plan to expand the extent and capacity of the city s sewage collection and address the need for treatment and proper disposal. The Distrito Turístico y Cultural de Cartagena de Indias and Aguas de Barcelona entered into a public/private partnership to upgrade and operate the utility. This entity, referred to as Aguas de Cartagena (ACUACAR), was successful in obtaining more than $110 million in loans from the World Bank and the Inter-American Development Bank for the project. ACUACAR retained Hazen and Sawyer to evaluate various wastewater treatment and disposal options and prepare an Effluent Disposal Feasibility Study. Due to the limited assimilative capacity of the Bahía and the fact that the southern portion of the 5,500-acre Ciénaga had turned eutrophic, lacking adequate dissolved oxygen to support aquatic life, Hazen and Sawyer staff initiated a comprehensive 12-month field effort which included background water quality and benthic sampling, and conductivity, temperature, and depth profiles of the open ocean. We also utilized tide gauges and an acoustic Doppler current profiler (ADCP) to characterize ocean currents, waves, and tides more than 30 miles off the Colombian coast. Effluent Disposal Feasibility Study The study consisted of developing and utilizing computer models to predict hydrodynamics, pollutant transport, initial dilution, and solids deposition. Twelve months of field data collection was conducted to monitor parameters including: Water quality Current patterns Tidal cycles Benthic soil characteristics Water column stratification More than 30 sample stations, located along the shore, within the Bahía, and in the vicinity of proposed outfall discharge locations, were monitored for parameters including BOD, TSS, total and fecal coliforms, Hazen and Sawyer collected and evaluated data for the Wastewater Master Plan. Tide gauges were installed at many locations, including the Islas del Rosario, to help determine a suitable location for the ocean outfall. 14 HORIZONS WINTER 2014

15 enterococcoci, total nitrogen, total phosphorus, phytoplankton, zooplankton, dissolved oxygen, temperature, and salinity. Tidal measurements were used as model input to predict hydrodynamic conditions within the study area. Current measurements were utilized to verify model results and to establish current magnitudes and direction at the proposed outfall locations. A detailed study of the local environment was critical to garner support from the citizens of Cartagena and the villagers of neighboring Punta Canoas, and to justify the project to the World Bank s independent panel of experts who were charged with assessing the proposed design prior to making a recommendation for funding. Placement of the outfall in an area of naturally high background turbidity and low biodiversity ensured the best possible protection of the environment during both construction and operation. The design of the diffuser to achieve a dilution of 100:1, while accommodating the lowest 10 th percentile current speed, coupled with the natural disinfection capability of the open ocean, ensured the best possible protection of the downstream public. Design and Construction Upon acceptance of the predesign, Hazen and Sawyer continued with detailed design for various components of the upgraded sewer system, including a new master pump station, a 72-inch conveyance pipeline that extended more than 12 miles, the new Punta Canoas Wastewater Treatment Plant, and a 72- inch diameter ocean outfall extending more than 2.5 miles and located 60-feet deep within the Caribbean Sea. With the treatment plant and open ocean outfall in service for only a few months, subsequent sampling results along the beaches have shown a marked reduction in bacteriological levels. The escalation of material prices wastewater generated. The plant at during the design process prompted Punta Canoas, the first wastewater the implementation of a unique outfall treatment plant in Cartagena s storied construction approach, wherein the history, will provide for the City s pipe was fabricated out of HDPE in sanitary health for the foreseeable Norway and towed in seven 1,500-feet future. sections by tug to Cartagena. At the For several years before outfall time of construction, the 72-inch I.D. implementation, ACUACAR collected pipe was the largest diameter solid wall monthly bacteriological samples at HDPE pipe ever fabricated. the beaches in order to measure Upon reaching the port, the pipe the degree of contamination along segments were joined together, fitted the shoreline. The data revealed with concrete ballasts and towed to the that total and fecal coliforms often outfall site, where a carefully controlled exceeded the recreational water air release from the seaward end quality standards by several orders of enabled connection to the pipe trench magnitude. With the treatment plant in the surf zone. Once positioned and and open ocean outfall in service lowered to the ocean floor, the diffuser for only a few months, subsequent was installed and the treatment plant sampling results along the beaches and outfall were placed into service in have shown a marked reduction the spring of in bacteriological levels, exhibiting Viable Future The upgrades to the sewage collection and transmission system now capture more than 95% of all 95 th percentile values well within Colombian standards. These water quality improvements have set the stage for recovery of the Bahía and Ciénaga. HORIZONS WINTER

16 hazenandsawyer.com GET THE LATEST RESEARCH NEWS sign up for our e-newsletter Articles reprinted from industry-leading publications such as WE&T and the AWWA Journal Detailed descriptions of our AWARD WINNING work Abstracts from ACE, WEFTEC and other conferences from around the globe