Montgomery County Water Services
Dayton, Ohio
Montgomery County Water Services (MCWS) is a regional water and sewer provider
with 11 water booster stations, 36 sewage lift stations, three equalization basins, and two
regional WWTPs (20 MGD and 13 MGD). MCWS provides an average 26 MGD
drinking water to 250,000 people. All drinking water is purchased from the City of
Dayton, OH. MCWS staff is comprised of 242 persons.
Responding to operational alarms and work requests at remote water and sanitary pump
stations often requires sending two people—one mechanic and one electrician. This often
creates unnecessary overtime as the corrective action usually requires either mechanical
or electrical repair—not both. In 2007, we began to study how to maintain core operation
and maintenance (O&M) responsibilities, save labor costs, provide improved mechanical
and electrical maintenance support using existing staff, and to develop better-skilled
maintenance employees. The ability to improve maintenance skills within the two
WWTPs was also examined.
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Posted: May 20th, 2011 | Filed under: 100K-500K, Stormwater, Waste Water Treatment, Water Treatment | Tags: Improved Employee Morale, Improved Maintenance, Improved Plant Reliability, Increased Equipment Service Life, Lobor Cost Savings, O&M Savings | No Comments »
Portland Water Bureau
Portland, Oregon
A key challenge faced by utilities in managing their infrastructure is the need to confidently
determine short and long term asset investment requirements without getting buried in the detail
or waylaid by the poor quality of data, for thousands of individual assets. The paper will discuss
an approach using management strategies to simplify the management effort, appropriately
model short and long term future investment needs for all assets, result in improved confidence
in the quality and confidence of the analysis, – even in situations of limited data – and enhance
improved capital improvement program programming. It presents the benefits, implications, and
applicability of using management strategies as described by the implementation for the City of
Portland Water Bureau on the development of their future investment needs.
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Posted: May 20th, 2011 | Filed under: 100K-500K, Stormwater, Waste Water Treatment, Water Treatment | Tags: Improved Maintenance Operations, Improved Plant Reliability, Optimized Decision Making, Reduced Modeling Processing Time | No Comments »
Reno-Stead Water Reclamation Facility
Reno, Nevada
The objective of this study was to demonstrate the effectiveness of an advanced treatment
process not utilizing reverse osmosis (RO) for removal of hormones, pharmaceuticals, and flame
retardants (collectively termed microconstituents or chemicals of emerging concern [CECs])
from municipal effluent. The advanced treatment process consisted of (in the order of use):
membrane filtration (MF), ozonation (O3), and biological activated carbon (BAC). The 15-
month, continuous flow, 10.7 gpm, MF-O3-BAC demonstration study was conducted in two
phases at the Reno-Stead Water Reclamation Facility (RSWRF): Phase 1 focused on ozone
process optimization and bromate mitigation; Phase 2 was a 10-month steady-state
demonstration of process performance. For RSWRF effluent, an ozone dosage of at least 5 mg/L
was needed for desired CEC removals. Peroxide (year-round) and ammonia (seasonal) were
added to mitigate bromate formation during ozonation. BAC removed flame retardants, and
ozonation byproducts including NDMA (N-Nitrosodimethylamine), aldehydes, and
biodegradable organic carbon. Findings of this study imply that MF-O3-BAC treatment is
equally effective as RO-based treatment for CEC removals, but with substantially less energy
utilization.
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Posted: May 20th, 2011 | Filed under: Stormwater, Waste Water Treatment, Water Treatment | Tags: Advanced Treatment Alternative, Contaminants of Emerging Concern (CEC) Removal, Cost Effective Treatment Process, Energy Savings, Environmental Impact, Improved Health | No Comments »
Various WWTP's
Various States
After manpower, energy is the highest operating cost item for most water and wastewater companies.
Over the last decade, energy consumption by the sector has considerably increased as a result of
implementation of new technologies to meet new effluent and potable water quality standards. High
energy consumption will affect the water industry worldwide and is inextricably linked to the issue of
Climate Change. Through its Optimization Challenge program, the Water Environment Research
Foundation (WERF) participated in the Global Water Research Coalition’s (GWRC) project titled Energy
Efficiency in the Water Industry: A Compendium of Best Practices and Case Studies. For this project,
WERF served the role of North America practice coordinator, developing a Compendium of best
practices in the energy efficient design and operation of water industry assets for this region of the world.
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Posted: May 20th, 2011 | Filed under: Stormwater, Waste Water Treatment, Water Treatment | Tags: Compendium of Best Practices, Cost Savings, Energry Efficiency, Energy Recovery Technologies, Energy Savings, Environmental Impact, Plant Optimization | No Comments »
Various WWTP's
Various States
Public agencies are increasingly pressured to become more sustainable. Wastewater plants are
significant consumers of energy and correspondingly produce significant quantities of
greenhouse gas (GHG). Reductions in energy and GHG are challenges for wastewater facilities
as flows and loads increase and discharge requirements become more restrictive. The results
highlight some methods to reduce energy and GHG, including the concept of becoming energy
neutral. Energy (as represented by electrical energy or fuels) equate directly to GHG production.
A significant portion of the fuel source for most utilities in the United States is from
anthropogenic sources such as coal, oil, or electric. To achieve energy neutral facilities, the
wastewater plant must implement energy conservation and shift to biogenically derived energy
sources, such as biogas, or alternative energy sources, such as wind. This paper and presentation
describe how wastewater treatment plants can significantly reduce energy to the point of
becoming energy neutral.
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Posted: May 20th, 2011 | Filed under: Stormwater, Waste Water Treatment, Water Treatment | Tags: Best Practices, Cost Savings, Energy Efficiency, Energy Savings, Environmental Impact, Improved Biogas Production, Plant Sustainability, Reduced Carbon Footprint, Reduced Greenhouse Gas Emissions | No Comments »
Various WWTP's
Various States
Energy consumption for municipal wastewater treatment accounts for 15% to 30% of the
operating cost at large treatment facilities and 30% to 40% at small facilities (WEF, 2009).
Energy costs are expected to continue escalating as a result of the rising price of fossil fuels used
for energy production while the energy demand for wastewater treatment is expected to grow as
the use of energy intensive treatment processes increases to meet water quality objectives that
may demand increasingly stringent wastewater discharge limits.
The United States Environmental Protection Agency (EPA) is committed to promoting energy
efficiency and implementation/use of energy conservation measures at municipal wastewater
treatment facilities. EPA, in partnership with The Cadmus Group and HDR, has undertaken a
project to identify and evaluate innovative energy conservation methods implemented at
wastewater utilities in the U.S. and report on their effectiveness in achieving reductions in energy
use and cost associated with wastewater treatment.
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Posted: May 20th, 2011 | Filed under: Stormwater, Waste Water Treatment, Water Treatment | Tags: Cost Saving, Energy Efficiency, Energy Savings, Environmental Impact, Operational Modification, Plant Sustainability, Process Control Enhancements, Reduced Carbon Footprint, Reduced Greenhouse Gas Emissions | No Comments »
This paper outlines how energy management planning can accomplish dual goals of
energy self-sufficiency and optimum treatment processing, and how this provides robust
performance and acceptable payback on investment, leading to net zero energy
wastewater operations. The energy content of wastewater surpasses the energy required
by treatment, reportedly be a factor of up to 10 times. Nevertheless, conventional
activated sludge plants with advanced treatment consume typically 1,800 kWh/MG of
electricity, but facilities vary from 1,000 to 3,000 kWh/MG. Energy efficiency studies
conclude that the potential for energy use reductions through efficient pumps and aerators
are on the order of 30 to 50 percent, which is a range of about 400 to 700 kWh/MG. For
plants with anaerobic digestion, a rule-of-thumb for electrical production from biogasfueled
generators is 500 kWh/MG. Supplementation of anaerobic digesters with high
strength organic waste and fats, oils and grease is possible where utilities have excess
digester capacity. The experience with supplementation is that facilities have increased
biogas by a factor of two or three times pre-existing conditions, and are able to have a
corresponding increases in electricity production, where generators have been adequately
sized. When thermal heat can be returned for plant processes, overall plant efficiencies
rise even higher. Energy planning studies have also shown that innovative technologies
that build upon anaerobic processes reduce energy usage from typical values, and,
further, energy plans have demonstrated some unexpected results, such as the economic
and environmental justification of anaerobic digestion combined with thermal processing,
such as dryers and incinerators. While local conditions, particularly energy pricing and
government subsidies, likely shape the specific planning objectives and outcomes of any
individual plant, the variety of energy efficiency and production technologies that are
becoming proven can result in a similar endpoint, and specifically net zero energy
wastewater treatment.
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Posted: May 20th, 2011 | Filed under: Stormwater, Waste Water Treatment, Water Treatment | Tags: Cost Savings, Energy Efficiency, Energy Savings, Environmental Impact, Plant Sustainability, Reduced Carbon Footprint, Reduced Greenhouse Gas Emissions | No Comments »
The development of the Carbon Heat Energy Analysis Plant Evaluation Tool (CHEApet) by
the Water Environment Research Federation (WERF) was in response to the identified need
for a predictive modeling tool that unifies prior WERF research information regarding
quantifying and managing energy consumption. CHEApet was created under OWSO4R07C
of WERF’s Optimization Challenge to model performance and energy consumption of waste
water treatment plants (WWTPs). Energy consumption, along with treatment process
emissions, contributes to a facility’s carbon footprint. CHEApet can be used to create a
baseline scenario, or inventory, of a utility’s carbon footprint for informational purposes as
well as to compare with hypothetical treatment plants. This kind of comparison allows the
user to identify facilities in the utility for energy optimization and the potential for biogas
recovery which can save in costs and improve the footprint of the facility.
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Posted: May 20th, 2011 | Filed under: Stormwater, Waste Water Treatment, Water Treatment | Tags: Biological Phosphorus Removal, Chemical Phosphorus Removal, Cost Savings, Energy Optimization, Energy Savings, Environmental Impact, Heat Drying, High Efficiency Air Diffusers, Improved Biogas Production, Phosphorus recovery, Plant Sustainability, Process Modeling, Reduced Carbon Footprint, Reduced Greenhouse Gas Emissions | No Comments »
Fayetteville Public Works Commission
Fayetteville, North Carolina
Fayetteville Public Works Commission (PWC) is implementing a number of renewable energy
projects. These projects include digester gas cogeneration at their Cross Creek Wastewater
Treatment Plant, solar panels to be installed as part of an innovative, sustainable design for a new
elementary school, and smart grid technology for their power distribution. These technologies
will allow PWC to reduce their power demands, reduce their carbon consumption and emissions,
and take advantage of renewable energy sources to meet the requirement for renewable energy
portfolio standards required by North Carolina Statutes. This paper will provide a description of
the smart grid and solar panel projects, and a more detailed discussion of the digester gas
cogeneration project. Cogeneration technologies that were evaluated include engine generators,
microturbines, and fuel cells. A comparison of technologies, capacities, implementation plans,
alternatives analyses, and cost evaluations will be discussed.
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Posted: May 20th, 2011 | Filed under: 50k-100k, Stormwater, Waste Water Treatment, Water Treatment | Tags: Cost Savings, Energy Savings, Environmental Impact, Green Infra, Improved Biogas Production, Plant Sustainability, Reduced Carbon Footprint, Reduced Greenhouse Gas Emissions, Solar Energy Utilization | No Comments »
City of North Port Wastewater Treatment Facility
North Port, Florida
Recent societal pressures to reduce the costs associated with energy consumption and the related
greenhouse gas emissions have created a driver that is an inconsistent with the traditional goals
of water quality and environmental protection. The conflict between these goals is particularly
compelling for wastewater treatment facilities (WWTFs), as more stringent effluent requirements
are being promulgated. By and large, it can be said that the greater the required level of treatment
– the greater the energy demand. In addition, both influent concentrations and the type of
biological treatment processes used to meet the regulatory requirements play a considerable role
of the factors that must be considered. In most cases, many facilities over aerate, with no regard
to how much air is required for the process in order to obtain adequate margin of safety against
permit exceedances. The result is that the actual discharge concentrations of these constituents
are well below the permitted discharge concentration, while a significant amount of energy is
wasted in accomplishing this.
Another concern facing utilities are diminishing freshwater supplies, impacts from climate
change, population growth, and more stringent effluent disposal and water quality limitations, all
of which have all placed greater demands on the development of reclaimed water facilities to
supplement the use of this resource in lieu of potable water. Not only can the use of reclaimed
water help conserve potable water by replacing potable water for certain non-potable water uses,
it can also help recharge groundwater supplies. As a result, utilities are finding synergistic
solutions to water supply, wastewater treatment and water resources management issues.
Therefore, the adequacy and protection of our water supplies will be one of the more challenging
issues that utilities will face in the 21st century.
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Posted: May 20th, 2011 | Filed under: 50k-100k, Stormwater, Waste Water Treatment, Water Treatment | Tags: Cost Savings, Energy Savings, Environmental Impact, Improved Effluent, Plant Sustainability, Reclaimed Water, Reduced Carbon Footprint, Reduced Greenhouse Gas Emissions | No Comments »