Phase I: Regional Demand
July 22, 2020
Prepared for the Indiana Finance Authority
Pursuant to Senate Enrolled Act 416 and the State of Indiana’s Water Infrastructure Task Force Final Report (dated November 9, 2018), the Indiana Finance Authority has begun to undertake a series of studies to identify water infrastructure needs and solutions, specific to regional areas of the State, as well as efficiencies to be gained through regional partnerships and improved sharing of resources.
The Indiana Finance Authority acknowledges the contribution of INTERA Incorporated and Dr. Benedykt Dziegielewski for the creation of this report.
This report was developed in consultation with a team of professionals from state and federal agencies. The team attended monthly meetings that included project updates and technical discussion of the water forecast methods. This group of dedicated water industry professionals and engineers helped guide the project by listening to our status reports while we were developing the forecast and then again with their patient and generous review of early drafts of this report.
We would like to express our sincere gratitude to the team members from:
We would also like to thank the regional water utility members of the Central Indiana Collaborative. This group was consulted during the project and provided an important public water supply perspective.
Citation: Indiana Finance Authority, 2020. Central Indiana Water-Supply Needs – 50 Year Forecast, Central Indiana Water Study, Phase I: Regional Demand, 184
Estimates of water use in the Central Indiana Water Supply Planning Region (Central Region or Region) were developed for the next 50 years for five major water demand sectors: 1) public supply, 2) self-supplied domestic, 3) self-supplied thermoelectric power generation, 4) self-supplied industrial and commercial and 5) self-supplied irrigation and agricultural uses. The forecast of future water use for each sector was developed at the county scale and then, separately, for each public water system at the facility level for all 52 dominant public systems. The primary goal of the Central Indiana Water Study (Study) is to provide a better understanding of the supply and demand of water resources in the Central Indiana region.
The methods used to forecast water use differed by sector and include multiple regression methods and unit demand estimates. These methods provided estimates of future water use as a function of demand drivers and explanatory variables for each of the sectors and subsectors. Explanatory variables are those that influence the unit rates of water demand, such as summer season temperature and precipitation, median household income, employment to population ratio, labor productivity, and precipitation deficits during the irrigation season. For most of the water uses in the Central Region, total demand was estimated by multiplying these unit rates for water use by forecast changes in the demand drivers. Demand drivers included the population served by public supply systems and self-supplied domestic wells, the expected number of employees, and gross estimates of thermoelectric power generation. This report makes use of the projections of the Indiana Business Research Center; alternative growth rates were not considered for population or socioeconomic growth.
For the public water supply sector, scenarios for future water demand were developed to reflect different future conditions, including climatic variability. These different drought and climate scenarios were used to capture the uncertainty in future water use and water demand within the Region.
Total future water demand in the Central Region was estimated to be 111 MGD (29%) more thancurrent withdrawals (2018) (Figure A). Demand for public water supply systems was the largest fraction of this increase. Expected growth in the Region will add over 500,000 people to the larger metropolitan area in the next 50 years (Figure B). Water use increases will primarily occur on the north side of the Region, in Hamilton County, with substantial growth also occurring in Johnson County to the south.
Total water use in this Region over the past decade has not increased substantially. Water use for thermoelectric power generation has declined as coal plants have been decommissioned throughout the Region and are being replaced by different fuel sources that use less water. In the past, thermoelectric cooling water has come from intakes along the White River. Future power generation is anticipated to come from more efficient generating facilities. The drinking water utilities that will experience the largest increase include Citizens Energy, serving the central metropolitan area and many suburbs, as well as other utilities that supply the larger communities in Hamilton and Johnson counties.
While total withdrawals from surface water have declined, use of groundwater from aquifers along the White River, will likely increase to accommodate growth. More than 100 MGD is forecast to be withdrawn from the outwash aquifer that follows the general path of the White River through the Region. This aquifer already supplies the majority of the groundwater used in the Region.
While uses of surface water for industrial and power cooling purposes have declined over the last several decades, use of groundwater for public water systems continues to grow as the metropolitan area expands. Agricultural irrigation will also likely increase, especially in the southeastern part of the Region in parts of Shelby and Johnson counties, where center pivot irrigation has become standard practice. Industrial demand, the most difficult of the water use sectors to forecast, will also increase as more businesses are created in and around the City of Indianapolis. Self-supplied domestic water use is assumed to remain the same over the next 50 years as some utilities expand to add service area in the unincorporated domains, and new homes are developed further away from the city. By the end of the forecast period, anticipated climate variation, change in temperature and precipitation, could potentially add between 10 and 35 MGD of additional demand in the dry summer months. Again, this demand will be focused on the north side of the Region and to the south where growth is expected to continue.
With approximately 40 inches of rainfall per year, Lake Michigan to the north, the Ohio River to the south, and streams and reservoirs in between, Indiana is considered a wet state. In an average sense, this is true. However, Indiana experiences seasonal and sometimes multi-seasonal droughts and rainfall shortages, that cause conflict and create uncertainty. During the drought of 2012, domestic well owners in some locations had dry wells or significantly declining groundwater levels. As climate change becomes a reality, these vulnerabilities are magnified and active water supply planning and management becomes critical to economic sustainability for the State. Water supply planning and management requires knowledge of the amount of water currently being used, how much will be needed in the future and if that water is available from the sources of supply.
The State of Indiana (State) has designated the Indiana Finance Authority (IFA) to coordinate water-related investigations to identify the water infrastructure needs and solutions for specific regions of the State. The Central Indiana Region (Central Region) was defined as a critical area for water planning. The goal of the Central Indiana Water Study (Study) is to provide a better understanding of the water resources, both water demand and water availability, in this area. The objective of the Study is to aid in the management, economic development and environmental health of the Central Region. The Study has been subdivided into five phases:
This report is the Phase I forecast of regional water demand. Estimates of future demand are presented in 5-year increments out to the year 2070.
The water supply used in the Central Region serves almost 30% of the population of the State and comes from diverse sources including withdrawals from the West Fork of the White River, storage in reservoirs, and groundwater from shallow and deep aquifers. The central portion of the state was chosen for evaluation because a group of water utilities has already organized and meets regularly to discuss their water supply, treatment, and regulatory issues. This group of utilities known as the Central Indiana Drinking Water Collaborative (Collaborative), conducts regular meetings to share information. The boundaries of the Collaborative region are the same as the Central Indiana Water Planning Region and include nine (9) counties centered around Indianapolis: Boone, Hamilton, Hancock, Hendricks, Johnson, Madison, Marion, Morgan, and Shelby counties (Figure 1.1).
The purpose of Phase I is to develop an estimate of current and future water withdrawals in the Central Region. The goal of the fifty-year water demand forecast (2020-2070) is to improve the understanding of current and future groundwater and surface water needs within the residential, commercial and industrial, power generation, and agricultural sectors of the Region. The forecast will be utilized in Phase III of the Study to assess the current and future availability of water resources.
Water use was forecasted on a county level in 5-year increments from 2020-2070 for each water supply sector, including:
The public water supply sector was further divided into forecasts per utility to capture the unique withdrawal patterns within each utility. A summary of withdrawals was tabulated for each county by adding up the public supply and other sector withdrawals for each forecast year. A baseline future scenario was developed for all sectors and drought and climate change scenarios were developed for the largest sector, public water supply. In addition, an analysis of the seasonality of public water supply withdrawals was included.
The forecasting techniques that were used differed by sector and include unit demand methods and multiple regression. These methods provided estimates of future demand as a function of demand drivers and explanatory variables for many sectors and subsectors. The water withdrawal forecast for each water sector is described in Sections 3 through 7. Additional data and graphs for each sector are provided in Appendices A through G.
This report is organized into an executive summary and ten sections. The executive summary discusses the goals and purpose of the study and summarizes the results for all water use sectors.
Section 1 provides the project introduction and discusses the data and analytical models used to estimate future water demands. Section 2 describes the current and historical water withdrawals in the Central Region. The five water use sectors are described in the five subsequent sections (Sections 3 through 7). Each of these sections briefly describes the water demand sector, summarizes the historical water withdrawals in the sector, and then explains the procedure for deriving water demand relationships for the sector. This is followed by summary of the sector results. Most sections are accompanied by one or more appendices containing detailed tables with primary data and other information used in deriving future water demand.
Section 8 describes the seasonal analysis of the public water supply sector and Section 9 shows the impacts on water withdrawals under simplified climate change scenarios, as well as the potential increase in water demands during a period of intense drought. Section 10 provides a summary of the regional water withdrawal forecast. References for all chapters appear at the end of the report.
Appendices A through G provide details and supplementary tables explaining how demand and population forecasts were made for each sector.
Future annual water use estimates are not attempts to estimate the actual water use next year. Instead we are estimating the average amount of water use expected over the next several years. A standard set of methods are used to consider how the factors that alter use may change in the future and then consider how those changes will alter average use over time. An example from San Diego County Water Authority is shown in Figure 1.2 (SDCWA, 2016). The chart shows the reported water use between 1995 and 2015. Although the annual use varies by plus or minus 25,000 acre-feet depending on precipitation and temperature, the average annual water use seems to increase in a predictable way between 1995 and 2007. An event such as the financial crisis of 2008 is not predicted by the forecast model and growth continues from the new reset after that time. The regional growth trend before and the long-term forecast after 2015 is analogous to the baseline forecast in the model – actual use will fluctuate around the forecasted increase. The water withdrawal forecast for the Central Region will similarly project annual average water use for the region, but will not capture the annual variations due to fluctuations in weather and other unforeseeable changes.
Historical water withdrawal data for the years of 2005-2017 were obtained from the Indiana Department of Natural Resources (DNR). The DNR maintains a database of Significant Water Withdrawal Facilities (SWWF) in the State. The SWWF database contains monthly water withdrawals reported by owners "for any ground or surface water source that either individually or in aggregate is" capable of withdrawing greater than or equal to 100,000 gallons per day (gpd) (DNR, 2018). The SWWF data has been reported to the DNR since 1985. The water users within the database are assigned a major water use category based on the primary use of the water at the facility. The six categories coded within the database are: IR (Agriculture/Irrigation), IN (Industry), PS (Public Supply), EP (Energy Production), RU (Rural Use), and MI (Miscellaneous). Data obtained from the SWWF database was divided into sub-sectors within each DNR water use category by sorting facility types by facility names. The sub-sectors were then re-grouped into four major water use sectors. This process is illustrated in Figure 1.3. The SWWF database was the source for all historical water use that is mapped to four of the five major sectors, as illustrated in the Figure 1.3.
Water use estimates in the fifth major sector, self-supplied domestic water supply (DWS), are based on population and per capita water-use in areas outside of public supply service areas. Domestic water supply consists of water supplied to homes with private wells. Water use data for private wells must be estimated, as private wells typically do not have the pumping capacity to require reporting to the State.
The data on water withdrawals in each sector were supplemented with corresponding data on demand drivers and explanatory variables for each demand area and sector. Demand driver data included: resident population and population served and employment population, gross and net thermoelectric generation. The explanatory variable data included: median household income; historical trends; air temperature during the growing season; and growing-season precipitation. Supplemental data on historical and future values of demand drivers and explanatory variables were obtained from a variety of state and federal agencies, including the Indiana Business Research Center, Indiana State Climate Office, U.S. Census Bureau, U.S. Department of Agriculture, U.S. Department of Labor Bureau of Labor Statistics, and the U.S. Energy Information Administration.
This study focuses on the forecast of water withdrawals based on voluntary reporting of monthly diversions from streams or groundwater. In this report, the terms water use and water demand are used interchangeably, and both terms are equated here with water withdrawals, as reported in the SWWF database: withdrawal, use and demand refer exclusively to the reported amount of water taken from a source such as a stream, reservoir, or aquifer.
Water withdrawals are not equivalent to consumptive use of water in the Region. Consumptive use is the amount of water used, either by a person, vegetation, or industry, that is not returned or discharged back to the source. Although a portion of the water withdrawals by each sector is considered non-consumptive, the unconsumed water is often returned to a source different from where it was obtained and often with altered water quality. Additionally, water can be withdrawn from one place and returned to geographically different location upstream, downstream, or in a different watershed. These diversions that alter the availability of the water supply are not considered in this phase of the Study. However, in Phase III of the Study, water availability will be evaluated and consumptive use will be analyzed to calculate the regional annual or seasonal water budgets for the Region. This water forecast is limited to determining the amount of water withdrawn from either surface water or groundwater sources within the Central Region.
Water withdrawals are forecasted for human water-use sectors only. The forecasts do not consider the needs of aquatic ecosystems and the environment. In Indiana, there are no regulated minimum flows for streams or other aquatic environments (DNR, 2015). Although quantifying flow requirements for ecosystems is technically complex and challenging, there is increasing awareness of the negative impacts that altered stream flows have on aquatic habitats and riparian zones. As water supply planning and management evolves in the State, ecosystem uses will likely need to be specifically incorporated into the planning process.
The analytical approach chosen for each water supply sector was based upon the best method for the best available data. The two principle techniques used in this report were the unit-use coefficient method and linear regression. The general approach of these methods is described below and additional information regarding the analytical methods, estimated models, and assumptions is included in the sections that describe each major sector of use.
The general approach to estimating future water demand using the unit-use method can be described as a product of the number of users (i.e., demand driver) and unit quantity of water as:
When historical water withdrawal relationships can be quantified, qt can be expressed in the form of equations. Thus, the average rate of water usage is expressed as a function of one or more explanatory variables, such as temperature or precipitation. A multiple regression analysis is used to determine the particular relationship between water withdrawals and each explanatory variable. This type of analysis was used in this study for the public water supply sector. The explanatory variables used for this sector were temperature, precipitation, and median household income. More details about the public water supply model are provided in Section 7
It is important to understand the uncertainty embedded in determining future water demands in any study area and user sector. This uncertainty is always present and should be considered when making regional water supply planning decisions. Generally, the error associated with the forecast values of water demand can come from the following sources:
Water withdrawals by public water suppliers were analyzed for seasonal fluctuations by examining the monthly historical water-use patterns of each utility. Typical seasonal variation occurs in response to annual weather changes: high temperatures and decreased precipitation drive customers to use more water in summer months. Further details about these seasonal analyses and the results are discussed in Section 2.
The U.S Environmental Protection Agency (EPA) developed the Climate Resilience Evaluation and Awareness Tool (USEPA CREAT) to help drinking water and wastewater utilities understand the potential system-related risks associated with climate change. CREAT provides projections of changes in climate change conditions based on averages of climate model outputs. To understand the range of potential impacts due to climate change in the Central Region, three scenarios were prepared for the public water supply sector. Using temperature and precipitation values from the climate change model output, the scenarios were incorporated into the public water supply forecast model. The scenarios include Warm/Wet Conditions, Hot/Dry Conditions, and a 30% Drought Condition. Further details about these scenarios and the results are discussed in Section 9.
The Indiana Department of Natural Resources (DNR) Division of Water maintains a Significant Water Withdrawal Facility (SWWF) database organized by the type of use. With the enactment of Indiana Code 14-25-7, beginning in 1985, any groundwater well or surface intake facility with the capacity to withdraw at least 100,000 gallons of water per day has been required to report monthly withdrawals each calendar year. This data, collected and assembled by type of use (irrigation, rural, mining, public supply, industrial, energy generation, and miscellaneous) provides the state with a unique window into the growth and change in water use throughout the state for the past 35 years. Currently, the records maintained by DNR include about 4,200 facilities with over 7,300 groundwater wells and almost 1,300 surface water intakes (DNR personal communication, 2020). The findings described in this report are based upon the information in that database supported by the staff at the Division of Water.
It is clear from the locations of the SWWF that there is more water withdrawal and use near the rivers and streams than further upland (Figure 2.1). This can partially be explained by surface and groundwater availability (more in the gravel-rich outwash aquifers and in the River than the tributaries and the thin till sands), but the use is driven by economic factors as well. The geography of water use is based on demographics and development, which historically follow major rivers and aquifers. One exception to this is mine dewatering operations where bedrock or aggregate is being mined.
Water use in the Central Region reported to DNR gives us some indication of the changes over time. The changes from large-scale manufacturing / industrial processing to professional services are reflected in the changing uses of water withdrawn from rivers and aquifers throughout the Region (Figure 2.2). The water use trends for each sector are described and the record of statewide use for each of the sectors is illustrated in the graphs on Figure 2.2 that follow.
Consistent with national water-use data, the largest water user in Indiana has been, prior to 2015, thermoelectric power for once-through cooling (Figure 2.2; USGS, 2017a). Technology, pricing and energy policy are changing as new fuels and generation methods enter the market and new rules are developed to stimulate non-hydrocarbon energy sources. Nevertheless, until 2013, power plants continued to use very large volumes of water. These cooling systems only consume a small fraction of the intake water and approximately 95 percent of the water withdrawals are returned as warmed effluent discharge. While more power generation facilities use groundwater than in the past, about 95 percent of all cooling water is withdrawn from streams and surface supplies. The energy production category represents relatively few registered SWWFs in Indiana; however, each requires large amounts of water. The power generation water use sector is unlike the other sectors as it has fewer facilities, each of which uses (and returns) a large fraction of the annual total withdrawal.
Figure 2.3 shows total water withdrawals for industrial use by state across the country in 2015. Indiana withdrew more industrial water than any other state that year. However, unlike other sectors of the economy, self-supplied industrial water use has been shrinking as a percent of total water use, both across the country and in Indiana. As one of the most heavily industrialized states in the nation, Indiana has documented a 35 percent reduction in industrial high-capacity water use over the period from 1985 to 2015 (Figure 2.2). The change is likely in response to a number of factors, among them globalization of manufacturing, the normal regulation of industrial wastewater discharge, and the general shift to more efficient operations that focus on streamlined logistics systems.
This trend of reduced industrial water use reflects an important change to the economy of the State that has occurred over the period of record. However, water is a valuable asset and the industrial history of Indiana is being used to attract new fabrication, manufacturing, and commercial enterprises. Industrial water use is an important component of what Indiana has to offer to manufacturers and industries.
While it plays an important role in the state’s economy, agriculture is not as much of a driver for water use in the Central Region. The agricultural component of the state’s gross domestic product (GDP) has monotonically increased over the past decade. Recent consolidations and mergers in the agricultural sector indicate that increases in water use will follow as the business of growing food and fuel demand increased management and higher profit margins. Over the last decade, the price of corn and soybeans has required that, even in historically moist areas, some farms add irrigation systems to ensure yields. Consequently, across the state irrigation water use has been the fastest growing category of SWWFs, more than doubling since the first year of the program (Figure 2.4).
In most of Central Indiana, the dominant water user is the community drinking water system. The Central Region has over 52 drinking water utilities that together supply over 200 MGD to the public (Figure 2.5). The water utilities in the Region supply water to more than 1.4 million people for domestic use (IFA, 2015). For a variety of reasons, seasonal variation of public supply withdrawals are becoming increasing with higher daily peaks relative to the average day. Much of this can be explained by synchronized lawn irrigation systems.
In the perimeter counties that surround Indianapolis, local water systems are responsible for more than 75 percent of all water use. Over the past two decades, more municipal systems are adding new wells to satisfy growth. Like many Midwestern cities, Indianapolis was built initially as a surface water supply system. Upstream of the city, river water is diverted into the canal that brings water into the intake of the main treatment plant. Wells, reservoirs and other intakes were added to the system to stabilize water quality and improve drought resilience (Figure 2.6).
Indiana has many very small water utilities with one or two wells connected to a small treatment plant to supply their communities. Depending on circumstances, the difficulty and cost of developing the source, treating and safely delivering the water to the end-user, while at the same time satisfying regulatory requirements, is a challenge (IURC, 2013). Historically these smaller drinking water utilities have operated relatively independently of each other, despite the fact that they may all use the same streams and aquifers. This independence reflects the fact that, until recently, there was little indication that their uses affected one another. The success in convening meetings among these regional water users for planning and coordination is a pre-requisite for model regional water management. These collaborative discussions are critical to providing the information the public needs to protect the resource.
Trends in average annual water use, like the ones forecast here, are useful for planning on a regional scale, but most utilities and other water users have higher demand during the warm season. These utilities need to pay attention to seasonal variation to manage supplies. Figure 2.7 shows that the regional, average-monthly water use increases during the warm months by about 30%. Public drinking water supplies are the largest water user in the Central Region, but commercial, industrial, power and irrigation water users are also important. For the mining and power sector, water withdrawals reflect mine production or power that supplies the electric grid. In the irrigation sector withdrawals are driven by temperature and the timing and duration of rainfall.
The seasonal curve and annual variation from responses to weather changes (e.g. drought) point to opportunities for conservation to reduce withdrawals. In other words, the increase in the warmer seasons can potentially be managed by conservation. It’s difficult to predict how much water demand reduction is achievable without having some historical data from implemented conservation efforts. While there is no regional data to analyze conservation, Citizens Energy Group (Citizens), which serves Indianapolis and most of Marion County (and portions of others), has data from the 2012 drought which highlights the impacts of voluntary and mandatory steps to manage demand during a water shortage (CEG, 2013). With a tiered drought response action plan already in place before the 2012 drought, the utility was able to effectively manage the drought through public response to water shortage triggers. The demand reductions achieved in 2012 are illustrated in Figure 2.8. The reductions were determined by modeling the expected demand that would have occurred without issuing the Tier 2 voluntary lawn watering ban or the Tier 3 mandatory lawn watering ban. Managing the seasonal curve can successfully be done with communication and cooperation with the public.
From 1985 to 2015, the largest volume of water used in the Central Region has consistently been for thermoelectric power generation (Figure 2.9). Since that period of time, however, the water use picture has changed dramatically. In the last several years power generation withdrew less water than other major users. As coal fired power plants have shut down in the Region, water use has fallen for power generation from over 500 MGD into the range of 50 MGD, below the combined use reported by self-supplied commercial and industrial users and well below the 200+ MGD used each year by drinking water systems. This shift in thermoelectric power generation water use is the most remarkable change illustrated by the history of reported water use in the Central Region. Because self-supplied commercial and industrial use is dramatically affected by the development of new businesses and manufacturers with access to the water resource, predicting future water use is difficult. Mining activity, driven by infrastructure investments, also adds to the commercial and industrial use category. Demand for drinking water in Central Indiana has increased as the population and economy have grown. Future increases will likely be satisfied by new high capacity wells completed in the outwash aquifer in combination with strategic local surface water storage.
In 2018, 64% of all the reported water use in the Central Region was withdrawn from a surface waterbody and much of that from the West Fork White River (Figure 2.10). This dependence on surface water is a common feature of the water supplies of major cities in the country, including Louisville, Minneapolis, Chicago, Cleveland, Atlanta, and Cincinnati. The Central Region diverted 232 MGD from Fall Creek, Eagle Creek, the West Fork White River, as well as reservoirs and quarries in 2018. Just less than 100 MGD of this water is treated for public supplies for Indianapolis, and the remainder is used for industrial process water and thermoelectric cooling. Another 100+ MGD of groundwater is used for public supplies in the Region. The Region has been shifting to groundwater to satisfy the local needs of growth. The southeastern portion of the Region is also using more groundwater to supply new irrigation wells (Figure 2.10). These two trends (i.e., increasing groundwater use for drinking water and irrigation) will determine if current resources can satisfy local demand. Fortunately, the most rapid growth of irrigation water use is in the northern portion of the State with more productive aquifers. Industrial water use and cooling water for power generation are not likely to grow in the next few decades.
Often, the Commercial and Industrial (C&I) Sector is defined to include both water that isself-supplied and water purchased from the Public Water Supply (PWS) Sector for commercial and industrial use. Presented here, because the SWWF database collects only self-supplied water withdrawals, the C&I Sector data include only self-supplied water withdrawals by industrial and commercial establishments. Water purchased for use by the C&I Sector is also in the PWS Sector,but only makes up a small percentage (less than 2%) of the public water supply sector(Section 7). C&I withdrawals represent approximately 20% of total reported water use in theState.
The C&I Sector has been divided into self-supplied mining and self-supplied non-mining sub-sectors for demand forecasting, as illustrated in Figure 1.3. In each sub-sector, the forecast is based on projections of future employment and historical rates of water use in gallons per employee per day (GPED). A summary of the historical data and the forecast for eachsub-sector is provided in this section. Additional data and county graphs are in AppendixA.
Self-supplied, non-mining withdrawals have decreased approximately 30% from 12.4 MGD in 2005 to 8.5 MGD in 2017 (Table ??). This reduction in water use is due, in part, to new efficiencies in production technology that function with lower water requirements for cooling and production. The largest withdrawals in this sub-sector occur in Marion County, accounting for over 50% of the Region total. Withdrawals in this sub-sector are primarily from groundwater, much of which is returned to surface water sources after use.
|County||Percent of delivered supply|
Because the future population of employees is the important factor in this analysis, we considered two employment forecasts for comparison. The first used rates of employment growth based on assumed values, which were related to historical rates and the projected statewide rates shown in Table 3.3. The second employment forecast was generated to verify the assumptions of the first, and uses the projections of the rates of growth in labor force by county. While the total county labor force is not the same as total county employment, the rates of growth in the labor force should be similar tothe rates of employment growth.
|County||2005-2017 Historical growth (%)||Assumed annual growth (%)||Explanation of assumed growth|
|Hancock||0.83||0.42||One half of historical rate*|
|Johnson||0.63||0.63||Historical close to Statewide rate|
|Madison||-0.89||0.20||Assumed slow growth vs. negative historical|
|Marion||-0.31||0.20||Assumed slow growth vs. negative historical|
|Morgan||-1.24||0.20||Assumed slow growth vs. negative historical|
|Shelby||-0.08||0.20||Assumed slow growth vs. negative historical|
The 12-year historical employment trends are unlikely to continue throughout the 2020-2070 forecast period. To address this variability, other information on expected growth in future employment was examined. According to the Indiana University Business Research Center, the average growth rate of total Gross State Product over the 2018-2039 period is projected to be 2.31% per year. Over the same period, total Indiana employment is projected to grow at a rate of 0.61%, with employment in manufacturing falling at a rate of 0.62% and non-manufacturing employment growing at a rate of 0.82% (IBRC, 2019). A summary of historical and assumed growth rates for the self-supplied, non-mining sub-sector is presented in Table ??, and estimates of future employment in the sub-sector are presented in Table ??.
|County||2005-2017 Historical annual trend||Assumed annual growth (%)||Explanation of assumed growth|
|Boone||0.00||0.00||Minor mining withdrawals in 2017|
|Hamilton||0.02||0.61||Statewide growth rate|
|Hancock||0.00||0.00||Minor withdrawals, no growth|
|Hendricks||0.00||0.00||No trend since 2010|
|Johnson||0.00||0.00||No growth in mining employment|
|Madison||0.00||0.10||Assumed slow growth vs. negative historical|
|Marion||0.00||0.61||Statewide growth rate|
|Morgan||-0.03||0.10||Assumed slow growth vs. negative historical|
|Shelby||-0.10||0.10||Assumed slow growth vs. negative historical|
Projected water demand in each county was calculated in 5-year increments through 2070 (Table ?? and Figure 3.10). Based upon the assumed rates of mining employment growth and the base year rates of per employee use, the mining water use forecast shows an increase in water withdrawals from 64.37 MGD in 2015 to 84.73 MGD in 2070. The greatest withdrawals are expected in Hamilton and Marion counties due to the presence of sand and gravel mining operations using large quantities of water. These operations involve pumping water for dewatering and washing. Water withdrawals in Hamilton, Madison, Marion, Morgan, and Shelby counties are expected to increase by 2070, while mining withdrawals in Boone, Hancock, Hendricks, and Johnson counties are expected remain low.
Throughout the world, irrigation (including water for agriculture, or growing crops) isone of the most important uses of water. Almost 70 percent of all the world’s freshwaterwithdrawals are for irrigation purposes (USGS, 2018). In the United States alone, irrigationwithdrawals were an estimated 118,000 million gallons per day (MGD) in 2015. The majority ofthese withdrawals (81%) and irrigated acres (74%) were in the 17 contiguous WesternStates where average annual precipitation typically is less than 20 inches (USGS, 2018).In Indiana, where the average annual precipitation is approximately 40 inches per year,water withdrawals for irrigation purposes in 2015 were estimated to be 133 MGD (USGS,2018).
The Irrigation and Agriculture (IR&AG) Sector includes water withdrawals from the followingsub-sectors, as illustrated in Figure 1.3: Crop/Orchard Irrigation, Golf Course Irrigation,Aquaculture/rural use, and Miscellaneous use. Of the five water sectors, IR&AG is the smallest,making up less than 5% of the total withdrawals in the Region. In 2015, 11.50 MGD were withdrawnfor agriculture and irrigation purposes in the Region.Future water withdrawal projections were based on historical trends of reported water withdrawals bycounty and agricultural sub-sector. Trends were calculated based upon variations in water-useutilizing 2005 to 2017 USGS data. The following sections describe the method and procedures used toforecast irrigation and agriculture withdrawals.
Water withdrawal data from 2005 to 2017, available from the DNR Significant Water WithdrawalFacilities (SWWF) database were evaluated (2018 data was unavailable at the time of analysis, butlater added to graphs and tables). Additional data from United States Geological Survey’s (USGS)National Water Information System (NWIS) (DNR, 2018) were also used to verify and supplementthe SWWF data. Total regional historical withdrawals ranged from 10 MGD in 2006 to 19 MGDin 2012 (Table ??). The annual variation in this sector is primarily driven by weatheras evidenced by increased in withdrawals in 2012 when Indiana experienced a drought.Weather-related increases occur in both the golf course and cropland sub-sectors. Othersub-sectors, such as aquaculture, are relatively stable throughout the thirteen-year historicalperiod.
The sub-sector water withdrawals also vary geographically (Figure 4.2). Marion, Hamilton, andMorgan counties comprise over 75% of the total withdrawals in 2018. Graphs of total waterwithdrawals for 2005 to 2018 for each county by withdrawal type are provided in Appendix B. InHamilton and Marion counties, golf course withdrawals are largest in the Region. Morgan Countywithdrawals are predominantly from one aquaculture farm. The largest volume of water used forcropland irrigation is in Shelby County.
|County||Sub-sector||Historical growth 2005-2017 (%)||Assumed growth 2020-2070 (%)|
Irrigation and other landscape water uses are driven by weather: more water is applied to crops when temperatures are high and precipitation is low. Ideally, when forecasting irrigation withdrawals, weather impacts are incorporated into the prediction by correlating the amount withdrawn (in million gallons/acre) to the temperature and precipitation during the time period. However, this is not possible in the Central Region. Although we have annual withdrawal data, we do not know the number of acres to which that water is applied. Without the acreage, we don’t know if increased withdrawals are due to weather or due to an increase in acreage. Therefore, future water demand projections were based on historical trends of reported water withdrawals by county and agricultural subsector. Trends were calculated based upon observed variation from 2005 to 2017. If growth trends were negative the assumed forecast trend was set to zero (resulting in constant values for all forecast years at the base year level). However, if the calculated historical trends were greater than 3% per year, then the assumed trend for the forecast was set at 3% per year or less. The base year irrigation water use was calculated as the average for the 5 most recent years (i.e., 2013-2017). The growth trends for each county are reported in Table 4.3 and 4.5.
|County||Sub-sector||Historical growth 2005-2017 (%)||Assumed growth 2020-2070 (%)|
A summary of historical and forecast IR &AG water withdrawals by sub-sector is presented in Figure4.1. The increase in withdrawals forecasted for the IR&AG Sector is small, from 12.75MGD in 2020 to 18.90 MGD in 2070 (Table ??). The growth is driven primarily by thethe crop/orchard sub-sector, increasing from 2.94 MGD to 7.64 MGD in 2070 (Figure4.1). More than half of the cropland withdrawals in the Central Region is projected tooccur in Shelby County (Table ??). Regionally, Shelby, Hamilton, Marion, and Morgancounties is projected to account for 85% of the irrigation and agriculture withdrawals in 2070.
The self-supplied domestic sector includes water withdrawn from private homeowner wells. Statewidemore than 25% of the people in Indiana drink water from a private well located on their property(USGS, 2017c). These domestic users are widely distributed and are not subject to management bystate agencies and unlike other sectors, withdrawals for this sector are not collected in theDNR SWWF database. Unfortunately, this makes it difficult to know the exact number ofpeople who use private domestic water wells and, therefore, methods of estimation must beapplied.
The two basic methods of water use estimation are based upon: 1) reported PWS populationserved numbers or 2) estimation of the population outside the PWS service areas (Figure5.1). The known value for both methods is the total county population. Then, either thetotal PWS population served is subtracted from the county population (Method 1) or thedomestic population is estimated using the number of parcels that are outside of service areas(Method 2). Both of these methods and the resulting water-use estimates for 2015 aredescribed in more detail in the following sections, however, the forecast for this report usedMethod 1, by subtracting the number of people served by the public water systems from the“known” population in each county (Figure 5.1). The PWS population served data usedwas reported by the utilities in a previous IFA study (Indiana Finance Authority, 2016).
A 2017 USGS report (Open-file Report 2017-1131) estimated the domestic water-use in 2015 for the United States (USGS, 2017c) and found that domestic self-supplied population has decreased from 2010 to 2015. Similarly, the domestic per capita use has decreased from 81 GPCD in 2010 to 77 GPCD in 2015 in the United States. For Indiana, the 2015 average per capita rate was 76 GPCD (USGS, 2017c) and we used this per capita rate to calculate the total county domestic use for the two methods.
It should be noted that in many communities around the country per capita urban water use has fallen over time as modern fixtures are added to apartments and homes. Recent investigations have shown that rural areas are not becoming more efficient (Sankarasubramanian et al, 2017) but the estimates used in this analysis show that rural uses are in line with national estimates. In this report, the “domestic use” covers only homes that use private wells. The estimated use of 76 gpcd is reasonable as it is close to the national average of 83 gpcd (indoor and outdoor) in the US in the 2015 USGS data. Other work by the AWWA Research Foundation (DeOreo, et al, 2016) showed that average indoor residential use was close to 53 gpcd.
This method estimates the self-supplied domestic population in each county by subtracting the 2015population served for each utility from the known total population of each county (Table 5.1). ThePWS population served was reported to the IFA directly by the utilities in IFA Utility Report (2016).When service territories crossed county boundaries, GIS tools were used with data such ascensus-block population to estimate the portion of population served in each county. In most ruralcounties there are only a few small water utilities, so the population that rely on domestic water wellscan reliably be determined by subtraction from the county census data. When the population servedby the utility is small, the magnitude of the error is also small relative to the total population in eachcounty. However, this estimation by subtraction method can be difficult near metropolitan areas.
|County||County population||Public-supplied population||Estimated domestic users||2015 Domestic water-use (MGD)*|
The total number of domestic water-users in the Region is estimated is 422,122. As a method check,we compared our domestic population estimate with the 2015 USGS domestic-use population values;385,326 people (USGS, 2017c). These two domestic population estimates have a difference of 36,796people, this translates into a difference of 2.8 MGD spread across the nine county Region, an arguablysmall difference.
Using Method 1 to estimate the domestic population and the USGS estimate of 76 GPCD, the 2015estimate of domestic withdrawals translates into just over 32 MGD of water withdrawals throughoutthe Region (Table 5.1).
An alternate approach to estimate the domestic-use was to count the number of land parcels in theareas outside of the public water supply service areas. After confirming that there were records ofprivate water wells on a large fraction of these parcels, an estimate was made of total domesticpopulation based on the average number of people per home in the rural areas outside of the PWSservice territories. The results of this method are provided in Table 5.2. This approach provided anindependent estimate that showed large differences in the most densely populated counties.
|County||Parcels w/out Public Supply||Estimated persons per parcel||Estimated domestic users||2015 Domestic water-use (MGD)*|
Using Method 2 to estimate the domestic population and the USGS estimate of 76 GPCD, the 2015 estimate of domestic withdrawals translates into 15.7 MGD of water homeowner withdrawals throughout the Region (Table 5.2).
Method 1 incorporates the data collected from the public water suppliers and, therefore, coordinates with the public supply forecast. However, Method 2 has ramifications to the public water supply sector because it yields alternative estimates for the population served values for each county. To analyze the difference this estimate will have on the public water supply withdrawals we have to calculate the new withdrawals generated by this bounding case. The population served was back-calculated in each county from the parcel estimated domestic supply. From this, we can re-calculate the 2015 public water supply withdrawals (Figure 5.2). As compared to the previously calculated public water supply withdrawals for 2015 (total 206 MGD, see Section 7), the average water use in 2015 is less by approximately 7.5 MGD.
The uncertainty in the domestic supply population could be managed with further investigation bythe County Health Departments in the Region. A survey of homeowner wells and water use wouldimprove the confidence in the forecast for water demand state-wide. However, the scattereddistribution of homeowner wells over the entire Region minimizes the hydraulic impacts of this sectoron other water uses.
Two forecasts were calculated; one using a constant GPCD and another that modified future GPCD with conservation and median household income (MHI) growth. Both forecasts applied the county population projections growth rates to the 2015 domestic population calculated using Method 1. The results of the two forecasts were very similar, resulting in a 2020 total domestic water-use of ~33.7 MGD and a 2070 projected total of 44.7 MGD in the Region. The results of the constant GPCD forecast are shown in Table ?? and Figure 5.4. The counties with the largest total population (Marion, Hamilton, and Hendricks) also have the largest domestic population and, therefore, the largest withdrawals for domestic supply.
Despite the importance of domestic water use by individual domestic well owners in some counties, it is difficult to accurately estimate domestic use with the limited data available. Water shortages caused by over pumping by high capacity wells or from lack of recharge, could cause serious disruptions in those rural areas served by self-supplied domestic wells. While these factors are important in the rural areas of the study region, additional investigation is needed to understand these risks. Given that we can only roughly estimate the average unit use (gpcd) and number of users (i.e., active wells as a sole source of water supply), we are limited to the accounting for this use by providing our best estimate.
Power generation has historically been water intensive, however, as fuel sources change and the generation process becomes more efficient, water use has declined. This trend is evident across the country and in the Central Region. In 2005, water withdrawals exceeded 360 MGD for power generation. In 2017, water use for power generation was reported to be less than 70 MGD. For this sector, separate forecasts of water demand were prepared for thermoelectric and geothermal power production. A straightforward unit-coefficient method was used in this study to derive future quantities of water withdrawals. This method represents cooling water demand as a product of total gross generation at the plant and the unit rate of water required in gallons per kilowatt-hour. The specific coefficients and relationship for the two main types of cooling systems are discussed below.
Water withdrawn by power plants is classified by the United States Geological Survey (USGS) as thermoelectric generation water use (USGS, 2017b). It represents the water applied in the production of heat-generated electric power. The heat sources may include fossil fuels such as coal, petroleum, natural gas, or processes such as nuclear fission. The main use of water at power plants is for cooling. Nearly 90 percent of electricity in the United States is produced with thermally-driven, water-cooled generation systems which require large amounts of water.
The three major types of thermoelectric plants include: conventional steam, nuclear steam, and internal combustion plants. In internal combustion plants, the prime mover is an internal combustion diesel or gas-fired engine. Since no steam or condensation cooling is involved, almost no water is used by internal combustion power generation.
In conventional steam and nuclear steam power plants, the prime mover is a steam turbine. Water is heated in a boiler until it turns into steam. The steam is then used to turn the turbine-generator, which produces electricity. While water demand for energy generation are similar for plants of the same type, the actual unit amounts of water withdrawn per kilowatt-hour of gross generation vary from plant to plant even when the same type of cooling is used and at the same level of thermal efficiency. Significant differences in unit water use per kilowatt-hour of electricity generation among different types of cooling systems were reported in previous studies (Harte and El-Gasseir, 1978; Gleick, 1993). Some of the reasons for this variability are easily explained. For example, in load-following plants using once-through cooling systems, intake pumps are left on when the level of generation declines. This is often caused by the lack of control technologies to regulate flow to match the fluctuating load on generators. There is limited ability to close or open control valves on pipes between the pumps and the condenser, or regulate the operation of pumps.
Better measurement and control of flows is available on closed-loop systems with cooling towers. The make-up water is usually metered and its flow rate could be regulated automatically depending on the quality of the recirculating water. However, the level of control varies among plants and the amounts of intake water per kilowatt-hour of generation also vary. Without advanced technologies for water measurement and control, it is difficult to optimize system operations to minimize water intake as well as operational costs associated with maintaining the high efficiency of heat transfer in the condenser. For these reasons, the water-use rate is calculated individually for each power plant (in gallons per kWh) and used for the future projection.
Three counties have thermoelectric power plants in the Region: Hamilton County, Marion County, and Morgan County. Water withdrawals reported for 2005-2017 for the largest thermal power plants in each county were obtained from the DNR Significant Water Withdrawal Facilities (SWWF) database and can be seen in Table ?? (DNR, 2018).Water withdrawals for thermoelectric power have decreased substantially from over 360 MGD in 2005 to less than 60 MGD in 2018, and is primarily due to facilities changing from coal to natural gas.
Table ?? describes the owner, capacity, and water-use of each plant. Hamilton County’s primary power plant is operated by Duke Energy Indiana LLC and withdraws the least amount of water in the Region. Marion County has three major plants: two operated by Indianapolis Power and Light Company (IPL) and one by Citizens Energy Group. Together these plants require the greatest water withdrawal of the Region. The IPL plant on Harding Street converted from coal to natural gas in 2016 resulting in significantly lower water withdrawal rates in 2017. Morgan County contains one power plant operated by IPL. The plant shifted from coal to natural gas in 2017 which will likely lower withdrawal in the following years. As evidenced in the reduction of water withdrawals per kWh, in particular, the Indianapolis Power and Light (IPL) Georgetown and Eagle Valley have changed fuel sources from coal to natural gas, which requires less water. Due to the monetary investment and efficiencies gained from the change in fuel source, it is assumed that the power generators will maintain the current fuel choice into the forecasted future.
|County||Owner||Facility Name||Fuel Type||Fuel Type||Capacity (MW)||Gallons/kWh in 2010||Gallons/kWh in 2017|
|Hamilton||Duke Energy||Noblesville||Natural Gas||300||0.64||0.13|
|Marion||IPL||Harding Street||Natural Gas||1196||11.42||10.60|
|IPL||Georgetown||Distillate Fuel Oil / Diesel||671||4.28||0.25|
|Citizens Energy||CC Perry K||Natural Gas||20||1296.50||249.70|
|Morgan||IPL||Eagle Valley||Natural Gas / Steam||158||51.18||2.71|
|County||Historical trend (2013 - 2017) (%)|
The public water supply (PWS) sector represents water withdrawals for both community and non-community water systems. The water supplier is generally publicly or privately owned and provides water to residential areas, commercial establishments, industry, and various institutions. This section summarizes the forecast for public water supply systems within the Central Region. Variables such as population growth, income, and climate are closely evaluated to estimate future water demand.
Using publicly available historical population and water-use data, projected water withdrawals by each public water provider were forecast from 2020 to 2070. Historical withdrawal data were examined to determine base year (2015) values of annual withdrawal (in MGD), population served, and per capita use (GPCD). This baseline forecast assumes historical average weather (normal weather) patterns will be observed into 2070. A modified per capita long-term forecast of PWS was prepared for each of the 52 individual water systems.
The water withdrawals reported in DNR Significant Water Withdrawal Facilities (SWWF) databasewere used for the forecast analysis. These data are reported by individual public water suppliers andare considered the best available data. However, additional data from the United States GeologicalSurvey’s (USGS) Water-use database were analyzed as a verification of these data and are presentedin the following paragraphs (USGS, 2017a).
Population served, as opposed to total population, is the number of people served by a public watersupplier within that supplier’s service area. Population served data collected from 1985 to 2015were obtained from the USGS water-use database (USGS, 2017a). Historically, populationserved by public water supply systems in the 9-county Region had been increasing at theannual (compounded) rate of 1.51 % (Table ??). Much of the growth was seen in Hamiltonand Hendricks counties as their populations increased at the rate of nearly 7 % per year.Madison County had the lowest observed population growth with an increase of 0.06 % peryear.
|County||1985||1990||1995||2000||2005||2010||2015||Trend/ Annual Growth Rate|
|County||1985||1990||1995||2000||2005||2010||2015||Trend/ Annual Growth Rate|
|County||1985||1990||1995||2000||2005||2010||2015||Trend/ Annual Growth Rate|
The DNR SWWF database reports annual and monthly withdrawals for all significant water users(able to withdraw 100,000 gallons per day), including public water suppliers. Tables ?? and ??summarize annual withdrawals obtained from the SWWF database for 52 public water systemswithin the 9 counties (DNR, 2018). Annual withdrawals showed increasing trends in 28 systems.
|Boone||Advance Water Works||0.04||0.04||0.04||0.04||0.03||0.04||0.06||0.06||0.07||0.08||0.05||0.07||0.05||0.057|
|Jamestown Mun. Water Work||0.07||0.07||0.07||0.06||0.06||0.06||0.06||0.06||0.06||0.06||0.06||0.06||0.06||-0.012|
|Lebanon Utility Service||1.76||1.66||1.90||1.75||1.52||1.50||1.56||1.67||1.51||1.53||1.73||1.77||1.64||-0.004|
|Town of Thorntown||0.14||0.15||0.16||0.15||0.15||0.13||0.12||0.13||0.12||0.13||0.11||0.11||0.11||-0.031|
|Lost Run Farm Community||0.00||0.00||0.00||0.00||0.11||0.11||0.11||0.11||0.11||0.12||0.11||0.13||0.13||0.311|
|Hamilton||Arcadia Water Department||0.16||0.14||0.15||0.13||0.13||0.13||0.13||0.13||0.13||0.12||0.12||0.12||0.14||-0.018|
|Atlanta Water Department||0.06||0.06||0.06||0.06||0.05||0.04||0.05||0.05||0.05||0.06||0.05||0.04||0.05||-0.021|
|Carmel Municipal Water||8.45||8.15||8.63||7.42||6.79||9.01||8.65||11.79||12.12||11.05||11.27||11.57||12.01||0.043|
|Citizens Water of Westfield||4.46||4.89||9.42||8.72||6.44||10.3||6.73||7.94||8.69||7.35||7.18||6.53||5.83||0.006|
|Indiana-American Water Co||3.04||3.29||3.87||3.70||3.60||4.02||3.88||4.25||3.95||4.07||4.29||4.27||4.19||0.022|
|Indiana-American Water Co||3.04||3.29||3.87||3.70||3.60||4.02||3.88||4.25||3.95||4.07||4.29||4.27||4.19||0.022|
|Sheridan Water Works||0.27||0.28||0.29||0.29||0.28||0.29||0.28||0.24||0.29||0.23||0.22||0.23||0.22||-0.022|
|Town of Cicero Utilities||0.43||0.43||0.46||0.49||0.47||0.50||0.40||0.44||0.49||0.47||0.46||0.46||0.41||-0.001|
|Hancock||City of Greenfield||3.04||2.92||3.07||2.97||2.62||2.68||2.56||2.76||2.72||2.76||2.67||2.59||2.47||-0.014|
|Gem Water/Town of Cumberland||0.09||0.09||0.14||0.11||0.10||0.11||0.11||0.12||0.11||0.13||0.12||0.16||0.20||0.051|
|Town of Fortville||0.56||0.51||0.54||0.60||0.51||0.59||0.48||0.44||0.43||0.38||0.39||0.45||0.53||-0.024|
|Hendricks||Danville Water Company||0.30||0.48||0.42||0.57||0.51||0.52||0.14||0.80||0.82||0.84||0.85||0.84||0.85||0.087|
|North Salem Water Corporation||0.05||0.05||0.04||0.04||0.03||0.03||0.03||0.04||0.03||0.03||0.04||0.04||0.03||-0.027|
|Town of Brownsburg||1.09||1.07||1.14||1.40||1.32||1.50||1.48||1.47||1.71||1.68||1.75||1.85||1.97||0.052|
|Town of Plainfield||4.06||3.98||3.01||3.97||3.61||4.09||4.40||4.70||4.60||4.31||4.22||4.29||4.65||0.018|
|Johnson||Bargersville Water Department||2.61||2.43||3.09||2.69||2.54||2.88||2.82||3.26||2.83||2.79||2.75||2.89||3.02||0.009|
|Indiana-American Water Co Inc||9.07||8.55||9.41||9.07||8.54||9.33||8.33||9.91||9.02||8.81||8.78||8.96||9.12||0.000|
|Princes Lakes Water and Sewage||0.01||0.01||0.01||0.01||0.01||0.01||0.01||0.01||0.01||0.01||0.01||0.01||0.01||-0.004|
|Town of Edinburgh||0.71||0.65||0.70||0.74||0.80||0.81||0.82||0.89||0.79||0.83||0.83||1.16||0.83||0.029|
|Madison||Alexandria Water Works||0.69||0.70||0.72||0.70||0.83||0.81||0.82||0.94||0.94||0.82||0.72||0.73||0.71||0.007|
|Anderson Water Department||3.71||3.55||4.43||5.02||5.01||5.58||5.32||5.20||5.29||5.57||5.74||5.74||5.54||0.032|
|Citizens Water of South Madison||0.00||0.24||0.30||0.43||0.26||0.22||0.27||0.22||0.28||0.68||0.95||2.29||0.77||0.394|
|Elwood Water Utility||2.53||2.17||2.30||1.82||1.43||1.38||1.14||1.22||1.34||1.30||1.14||1.13||1.18||-0.073|
|Indiana-American Water Co Inc||0.10||0.11||0.09||0.09||0.07||0.07||0.06||0.06||0.06||0.07||0.06||0.06||0.06||-0.058|
|Ingalls Water Department||1.13||1.23||1.22||1.06||1.09||1.06||1.11||1.03||1.07||0.97||1.02||1.08||1.09||-0.011|
|Pendleton Municipal Water||0.30||0.29||0.30||0.15||0.29||0.31||0.26||0.29||0.26||0.28||0.47||0.47||0.49||0.057|
|Town of Chesterfield||0.31||0.35||0.33||0.32||0.32||0.33||0.32||0.28||0.25||0.29||0.28||0.24||0.23||-0.027||Town of Edgewood||0.18||0.17||0.19||0.17||0.19||0.18||0.16||0.16||0.16||0.16||0.15||0.16||0.15||-0.018||Town of Frankton||0.21||0.21||0.20||0.22||0.21||0.20||0.20||0.22||0.21||0.24||0.29||2.94||0.25||0.337||Town of Orestes||0.04||0.04||0.04||0.04||0.04||0.04||0.03||0.04||0.05||0.07||0.05||0.03||0.03||0.009||Marion||City of Lawrence Utilities||4.58||4.47||5.04||4.79||4.18||4.21||4.34||4.16||4.49||4.74||3.95||4.22||4.32||-0.008|
|Town of Speedway||2.70||2.71||2.66||2.31||2.09||2.30||2.27||2.28||2.29||2.29||2.30||2.07||2.01||-0.020|
|Citizens Energy Group||151.6||152.0||168.0||148.4||141.4||140.3||137.5||135.5||133.7||120.5||124.5||124.8||125.3||-0.023|
|Morgan||Brown County Water Utility||1.14||1.16||0.90||1.10||1.30||1.01||1.22||1.08||1.18||1.23||1.32||1.33||1.32||0.018|
|City of Martinsville||1.77||1.50||1.43||1.41||1.25||1.53||1.60||1.67||1.56||1.57||1.51||1.54||1.57||0.002|
|Indiana-American Water Co||1.08||1.05||1.10||1.03||0.99||1.04||1.00||1.06||1.03||0.91||0.91||0.94||0.97||-0.012|
|Mapleturn Utilities Inc||0.16||0.14||0.16||0.15||0.15||0.20||0.19||0.18||0.15||0.14||0.13||0.14||0.15||-0.007|
|Morgan County Rural Water||0.54||0.56||0.61||0.61||0.34||0.45||0.41||0.51||0.52||0.52||0.58||0.58||0.59||0.005||Painted Hills Utilities||0.11||0.12||0.12||0.13||0.13||0.14||0.13||0.13||0.13||0.13||0.13||0.13||0.11||0.003||Town of Brooklyn||0.09||0.09||0.09||0.09||0.10||0.10||0.08||0.09||0.11||0.11||0.09||0.08||0.18||0.030||Town of Morgantown||0.10||0.08||0.09||0.09||0.04||0.08||0.08||0.08||0.08||0.08||0.07||0.07||0.07||-0.012|
|Town of Paragon||0.05||0.05||0.05||0.05||0.04||0.04||0.04||0.03||0.03||0.04||0.03||0.03||0.04||-0.033|
|Shelby||Indiana-American Water Co||3.41||3.01||3.25||2.94||2.75||2.71||3.17||2.95||3.24||3.02||3.10||2.97||0.04||-0.002|
|Town of Morristown||0.54||0.54||0.63||0.58||0.57||0.59||0.54||0.58||0.54||0.58||0.61||0.62||0.61||0.006|
|Town of St. Paul||0.05||0.08||0.11||0.08||0.08||0.08||0.07||0.08||0.08||0.09||0.08||0.07||0.08||0.003|
|Waldron Conservancy District||0.06||0.06||0.06||0.06||0.05||0.06||0.06||0.06||0.06||0.05||0.06||0.06||0.07||0.002|
|County||Elasticity of Precipitation||Elasticity of Average Air Temperature||Elasticity of Median Household Income|
|County||Water Supply System/Utility||2020||2025||2030||2035||2040||2045||2050||2055||2060||2065||2070|
|Boone||Advance Water Works||0.07||0.08||0.09||0.09||0.10||0.10||0.10||0.10||0.10||0.11||0.11|
|Jamestown Mun. Water Work||0.06||0.07||0.08||0.08||0.08||0.09||0.09||0.09||0.09||0.09||0.09|
|Lebanon Utility Service||1.86||2.04||2.20||2.32||2.40||2.46||2.53||2.58||2.62||2.65||2.67|
|Town of Thorntown||0.13||0.14||0.15||0.16||0.17||0.17||0.18||0.18||0.18||0.18||0.19|
|Lost Run Farm Community||0.14||0.15||0.16||0.17||0.17||0.18||0.18||0.19||0.19||0.19||0.19|
|Hamilton||Arcadia Water Department||0.13||0.14||0.16||0.17||0.18||0.19||0.20||0.20||0.21||0.21||0.22|
|Atlanta Water Department||0.05||0.06||0.06||0.07||0.07||0.08||0.08||0.08||0.09||0.09||0.09|
|Carmel Municipal Water||12.50||13.77||15.11||16.30||17.24||18.04||18.82||19.52||20.14||20.67||21.14|
|Citizens Water of Westfield||7.72||8.51||9.33||10.07||10.65||11.14||11.63||12.06||12.44||12.77||13.06|
|Indiana-American Water Co||4.66||5.13||5.63||6.07||6.42||6.72||7.01||7.27||7.52||7.70||7.88|
|Sheridan Water Works||0.25||0.28||0.31||0.33||0.35||0.37||0.38||0.42||0.41||0.42||0.43|
|Town of Cicero Utilities||0.51||0.56||0.62||0.67||0.70||0.74||0.77||0.80||0.82||0.84||0.86|
|Hancock||City of Greenfield||2.84||3.02||3.20||3.35||3.49||3.61||3.72||3.84||3.96||4.07||4.17|
|Gem Water/Town of Cumberland||0.15||0.16||0.17||0.17||0.18||0.19||0.19||0.20||0.20||0.21||0.22|
|Town of Fortville||0.43||0.46||0.48||0.51||0.53||0.55||0.56||0.58||0.60||0.61||0.63|
|Hendricks||Danville Water Company||0.92||1.00||1.08||1.16||1.22||1.28||1.33||1.39||1.44||1.48||1.53|
|North Salem Water Corporation||0.04||0.04||0.05||0.05||0.05||0.06||0.06||0.06||0.06||0.07||0.07|
|Town of Brownsburg||1.91||2.07||2.24||2.41||2.55||2.67||2.78||2.89||2.99||3.09||3.18|
|Town of Plainfield||4.63||5.03||5.44||5.85||6.19||6.48||6.74||7.01||7.26||7.49||7.71|
|Johnson||Bargersville Water Department||2.98||3.14||3.29||3.42||3.53||3.63||3.72||3.80||3.86||3.92||3.97|
|Indiana-American Water Co Inc||9.37||9.89||10.37||10.78||11.12||11.42||11.71||11.95||12.17||12.35||12.51|
|Princes Lakes Water and Sewage||0.80||0.84||0.88||0.92||0.95||0.97||1.00||1.02||1.03||1.05||1.06|
|Town of Edinburgh||0.99||1.05||1.10||1.14||1.18||1.21||1.24||1.27||1.29||1.31||1.33|
|Madison||Alexandria Water Works||0.75||0.74||0.73||0.72||0.70||0.69||0.68||0.68||0.68||0.68||0.68|
|Anderson Water Department||5.61||5.56||5.48||5.39||5.29||5.19||5.10||5.11||5.11||5.12||5.13|
|Citizens Water of South Madison||1.29||1.28||1.26||1.24||1.22||1.20||1.17||1.18||1.18||1.18||1.18|
|Elwood Water Utility||1.17||1.16||1.15||1.13||1.11||1.09||1.07||1.07||1.07||1.07||1.07|
|Indiana-American Water Co Inc||0.06||0.06||0.06||0.06||0.06||0.06||0.05||0.05||0.05||0.05||0.05|
|Ingalls Water Department||1.01||1.00||0.99||0.97||0.95||0.93||0.92||0.92||0.92||0.92||0.92|
|Pendleton Municipal Water||0.40||0.40||0.39||0.38||0.38||0.37||0.36||0.36||0.36||0.37||0.37|
|Town of Chesterfield||0.27||0.26||0.26||0.26||0.25||0.25||0.24||0.24||0.24||0.24||0.24||Town of Edgewood||0.15||0.15||0.15||0.15||0.14||0.14||0.14||0.14||0.14||0.14||0.14||Town of Frankton||0.26||0.26||0.26||0.25||0.25||0.24||0.24||0.24||0.24||0.24||0.24||Town of Orestes||0.05||0.05||0.05||0.05||0.05||0.05||0.05||0.05||0.05||0.05||0.05||Marion||City of Lawrence Utilities||4.39||4.45||4.49||4.53||4.57||4.61||4.64||4.66||4.68||4.68||4.69|
|Town of Speedway||2.26||2.29||2.32||2.33||2.36||2.37||2.39||2.40||2.41||2.41||2.41|
|Citizens Energy Group||126.20||128.38||130.22||131.84||133.52||135.15||136.72||137.82||138.74||139.52||140.15|
|Morgan||Brown County Water Utility||1.31||1.32||1.33||1.34||1.33||1.32||1.31||1.31||1.31||1.31||1.31|
|City of Martinsville||1.55||1.57||1.59||1.59||1.58||1.57||1.56||1.56||1.56||1.56||1.56|
|Indiana-American Water Co||0.93||0.94||0.95||0.95||0.95||0.94||0.93||0.93||0.93||0.93||0.93|
|Mapleturn Utilities Inc||0.14||0.14||0.14||0.14||0.14||0.14||0.14||0.14||0.14||0.14||0.14|
|Morgan County Rural Water Co||0.57||0.58||0.58||0.58||0.58||0.58||0.57||0.57||0.57||0.57||0.57||Painted Hills Utilities||0.13||0.13||0.13||0.13||0.13||0.13||0.13||0.13||0.13||0.13||0.13||Town of Brooklyn||0.09||0.09||0.09||0.09||0.09||0.09||0.09||0.09||0.09||0.09||0.09||Town of Morgantown||0.08||0.08||0.08||0.08||0.08||0.08||0.08||0.08||0.08||0.08||0.08|
|Town of Paragon||0.04||0.04||0.04||0.04||0.04||0.04||0.04||0.04||0.04||0.04||0.04|
|Shelby||Indiana-American Water Co||3.13||3.15||3.15||3.14||3.09||3.06||3.02||3.02||3.02||3.01||3.01|
|Town of Morristown||0.61||0.61||0.61||0.61||0.60||0.59||0.59||0.59||0.58||0.58||0.58|
|Town of St. Paul||0.08||0.08||0.08||0.08||0.08||0.08||0.08||0.08||0.08||0.08||0.08|
|Waldron Conservancy District||0.06||0.06||0.06||0.06||0.06||0.06||0.05||0.05||0.05||0.05||0.05|
Temperature is also positively correlated with water usage with a further interdependence on seasonalfluctuation. Residents use greater water during the summer months than cooler months. Temperatureelasticities ranged from 0.07 to 0.60 with the greatest elasticity in Hamilton County and the lowest inMadison County. Precipitation on the other hand is negatively associated with water withdrawalprimarily due to rainfall providing greater natural water availability for lawn and garden irrigation.Precipitation elasticities were expected to be smaller than the other two variables and ranged from-0.015 to -0.11. The greatest precipitation elasticity was calculated in Hamilton County and the lowestin Boone County. For this baseline scenario, normalized weather was assumed. Normalweather is the average conditions experienced for the 30-year time span of 1980-2010.Recognizing that there is seasonal dependence of climate variables such as temperature andprecipitation, water withdrawal rates were also forecasted for various climate scenarios (see Section9).
The application of historical or assumed future trends used the formula:
where: FV= future value (income ratio), BYV=base year value, r=annual growth/decline rate, fy=future year
For each five-year increment from 2020 to 2070, population-served size was calculated using estimatedgrowth rates, and GPCD was recalculated to include expected county median household income(MHI) elasticity and corresponding income ratio. The annual growth of future MHI was assumed at0.6 % per year. The assumption is based on historical data and compared to some statewideprojections. For the state of Indiana, the long-term (35 years) income growth was 0.30 percent/year(FRED, 2020). The future per capita use rates were also assumed to be affected by the ongoing waterconservation trend, which was assumed at -0.2 % per year. The forecast for each utility isshown in Tables ?? - ??. Graphs for each of the utility forecasts are provided in AppendixD.
Water use and water withdrawals are, in part, driven by the weather as reflected in the public supply model. In that model (see Section 7), the elasticities for temperature and precipitation were calculated for each water utility and capture how water withdrawals are affected by weather. Temperature is positively correlated with water usage, meaning water use is greater during the summer months than cooler months. Precipitation on the other hand is negatively associated with water withdrawal, meaning water use decreases with more rainfall by providing more availability for lawn and garden irrigation. The weather effect is evident in monthly fluctuation of withdrawals reported in the SWWF database. Through examination of the monthly data for each utility reported from 1985-2017, seasonal effects are apparent for some utilities.
The monthly values are obtained by redistributing average annual MGD by calendar months. The percent of annual use during each month was calculated as average from historical water use data. For example, on average Carmel Municipal Water in Hamilton County uses 15% of the annual water withdrawals in July and 5% of the annual water withdrawals in January. This seasonal variation is evident regionally as seen in Figure 8.1, however, a closer examination of county and utility data reveals that the seasonal trends are only in four counties; Hamilton, Hendricks, Johnson, and Marion. Graphs of the individual public water supply utilities, provided in Appendix E, show that, in fact, the seasonal trend is evident in only five utilities; Carmel Municipal Water, Town of Plainfield, Indiana American Water Company (Johnson Co.), Bargersville Water Department, and Citizens Energy Group. In particular, Citizens Energy Group and Carmel Municipal Water have the largest summer/winter divergence of water withdrawals. These two utilities withdraw double in the summer as in winter. Seasonal variation for each county and individual utilities in each county is provided in Appendix E.
The following analysis of climate change impacts on water demand is necessarily general. As notedpreviously, the scope and scale of this investigation does not allow for a high-resolution assessment ofhow some climate change scenarios could stretch seasons or alter the seasonal cycles. In this work,climate change is a shift from historically observed climate conditions as a result of natural processesand human-induced greenhouse gas emissions.
The changes in climate will place additional stress on water availability and resources. To adequatelyaddress future water demand within the Public Water Supply (PWS) sector, climate projections wereapplied to Public Water Supply (PWS) withdrawals as a means of assessing water demand over arange of conditions. The U.S Environmental Protection Agency (EPA) developed the ClimateResilience Evaluation and Awareness Tool (USEPA CREAT) to help drinking water andwastewater utilities understand the potential system-related risks associated with climatechange. CREAT provides projections of changes in climate change conditions based onaverages of climate model outputs. To understand the range of potential impacts due toclimate change in the Central Region, three scenarios were prepared for the public watersupply sector. The climate scenarios represent conditions based on the average of fiveclimate models utilizing higher temperatures/less precipitation (Hot/Dry scenario), moderatetemperature increases/greater precipitation (Warm/Wet scenario), and historical droughtscenario (30% less precipitation than the Hot/Dry scenario). The 30 percent drought isclose to what we experienced in 1963. The various moisture/temperature climate changescenarios are meant to consider the impact of these future climate regimes becomes our new baseline.
This chapter focuses on a range of climate scenarios and their impact on public water supplywithdrawals by public and private establishments within the Central Region.
|Scenario Name||Temperature change (°F)||Precipitation change (%)|
|Hot/Dry||3.1 - 3.2||6.0 - 6.2||-0.3 - -0.6||-0.5 - -1.2|
|Warm/Wet||2.3||4.4 - 4.5||6.0 - 6.5||11.7 - 12.6|
|Severe Drought||3.1 - 3.2||6.0 - 6.2||-30||-30|
In the previous section of the report (see Section 7), regional public water supply withdrawals wereforecast into 2070 using baseline (2015) conditions and normalized weather (average 1980-2010). Inthese climate change scenarios, public water withdrawals are the forecasted into 2070 using thepredicted relationship between water demand and climate change with conditions projected by theU.S Environmental Protection Agency’s Climate Resilience Evaluation and Awareness Tool (USEPACREAT) (EPA, 2016). Critical to its use in this report, CREAT is one of the tools used bywater utilities to evaluate the risk of climate change on water supply. The fact that this approach to defining the risks of climate change has been adopted by leading water systems inthe country gives us confidence that these scenarios will be useful to the Central Region, especially because the Region’s water withdrawals are dominated by public water supply. The CREAT Methodology Guide describes the approach for addressing climate change risks as follows:
CREAT provides projected changes from Global Climate Models17 (GCMs) as available from the Coupled Model Intercomparison Project, Phase 5 (CMIP5). CREAT uses an ensemble-informed approach to derive meaningful choices from the results of 38 model runs for each 0.5 by 0.5 degree location. This approach involves generating a scatter plot of normalized, projected changes in annual temperature and precipitation by 2060 for all models. Statistical targets were calculated based on the distribution of these model results and the five models closest to those targets were averaged to generate each projection (Figure 5). The targets were designed to capture a majority of the range in model projections of changes in annual temperature and precipitation, as follows:
Once the models for each projection were selected, these models were ensemble-averaged to calculate annual and monthly changes for temperature and precipitation. CREAT selects the most appropriate data to match the defined planning horizon from two available data sets – one for 2035, which is based on projection data for 2025-2045, and one for 2060, which is based on projection data for 2050-2070. The selection of the appropriate CREAT-provided time period is based on the End Year defined by the user during the time period selection. If the End Year is 2049 or earlier, the 2035 data are selected; otherwise, CREAT selects the 2060 data set.
To account for each climate scenario, temperature and precipitation ratios were applied to the GPCDfor each five-year projection, that was then translated to annual withdrawal. The temperature andprecipitation ratios for the H/D and W/W climate scenarios were calculated using the followingequations:
Monthly withdrawals were forecasted for the years 2035 and 2070 using the monthly fraction of annualwithdrawal by each utility per county. These monthly fractions for each utility were calculated fromthe average historically observed monthly data (2008 to 2017).
The water demand forecast applied historical water-use data from the Indiana Department of Natural Resources (DNR), which provided annual withdrawal estimates in 53 water systems in the Region. The period of record extended from from 2005 to 2017 (DNR, 2018). The data set was reproduced in Section 7. To assess the impact of climate change on temperature and precipitation on both a monthly and annual basis, a baseline of historically observed weather recorded in each county was assembled (Table 9.2). These values became the reference points for annual precipitation and average annual temperatures used to estimate alternative climate scenarios in the project area. For each analysis the average annual values were decomposed into a monthly distribution. The seasonal fluctuation in water use in each month is based on the relationship between use in that month and the annual average water withdrawal.
|County||Precipitation (inches)||Temperature (°F)|
The Hot/Dry (H/D) annual and monthly forecasts were estimated for each utility per county. The annual projections were conducted in five-year increments into 2070, whereas the monthly projections were limited to the years 2035 and 2060 (EPA, 2016). The H/D climate scenario is characterized by the following changes in temperature (°F) and precipitation (%) (Table 9.3). The H/D scenario predicts relatively constant increases in temperatures, with Morgan and Johnson Counties expected to experience slightly greater temperature increases by 2035 and 2060. Marion and Hendricks Countiesare expected to see the greatest decrease in precipitation (%) in 2060.
|County||Boone||Temperature (°F)||Precipitation (%)|
The Warm/Wet (W/W) annual and monthly forecasts were estimated for each utility per county. The annual projections were conducted in five-year increments into 2070 and the monthly projections were limited to the years 2035 and 2060 (EPA, 2016). The W/W climate scenario is characterized by the following changes in temperature (°F) and precipitation (%) (Table 9.4). With the exception of a few counties, the W/W scenario predicts temperature and precipitation increases in 2035 and 2060 to be relatively constant across the region with average increases in precipitation of 6.3% in 2035 and 12.3% in 2060.
|County||Boone||Temperature (°F)||Precipitation (%)|
Historically, the driest year for Indiana occurred in 1963 with mean precipitation measuring 29.32 inches, which is a 30% deficit of the annual, normal precipitation of 41.5 inches. To simulate a similar drought, the 30% drought scenario predicts 70% of precipitation anticipated in the H/D scenario will occur with the same expected temperature increases in both 2035 and 2060 (EPA, 2016). This scenario shows that the peak use in this case would increase in the range of 30 MGD from the baseline. This level of regional hydrologic deficit was experienced by the region in 1963. Active collaboration among the utilities will be required to provide for communities that endure such a drought.
Using the combination of climate variables for each scenario, withdrawal per county in 2035 and 2070 was forecasted on an annual and monthly basis (Figure 9.8 and Tables ??- ??). Individual county graphs of the climate change scenario forecasts are provided in Appendix G. For all scenarios, the predicted withdrawals are expected to increase from the baseline scenario, particularly in the summer months. In the drought scenario, the August withdrawals are expected to increase over 30 MGD in relation to the baseline forecast.
Total water use in this Region over the past decade has not increased substantially. Water use for thermoelectric power generation has declined as coal plants have been decommissioned throughout the Region and are being replaced by different fuel sources that use less water. In the past, thermoelectric cooling water has come from intakes along the White River. Future power generation is anticipated to come from more efficient generating facilities. The drinking water utilities that will experience the largest increase include Citizens Energy, serving the central metropolitan area and many suburbs, as well as other utilities that supply the larger communities in Hamilton and Johnson counties. Projected water uses in each of the counties in the Region reflect the population in each county as well as the industrial and power sectors located within the county (Figure 10.1). For most counties, the public water supply sector accounts for over 50% of the total water withdrawals.
Total future water demand in the Central Region was estimated to be 111 MGD more than current withdrawals (2018) (Figure 10.2 and Table ??). Demand for public water supply systems was the largest fraction of this increase in the Region. The geography and timing of the anticipated increase is critical for resource and infrastructure planning. Figure 10.2 shows rapid growth occurring in the Region, particularly in Hamilton, Boone, and Hendricks counties. Increased management of the supplies in these areas will be necessary to develop and protect source waters in a way that ensures the sustainability of the regional supply, especially during drought. Additional data and cooperation are likely going to be important to regional growth. Meeting future needs and developing the supplies in a way that is both economical and sustainable is the challenge for regional utilities for the next 50 years.
While total withdrawals from surface water have declined, use of groundwater from aquifers along the White River will likely increase to accommodate growth. More than 100 MGD is forecast to be withdrawn from the outwash aquifer that follows the general path of the White River through the Region. This aquifer already supplies the majority of the groundwater used in the Region.
Surface water withdrawals for industrial and power cooling purposes has declined over the last several decades as use of groundwater for public water systems continues to grow and the metropolitan area expands. Agricultural irrigation will also likely increase, especially in the southeastern part of the Region in parts of Shelby and Johnson counties, where center pivot irrigation has become standard practice. Industrial demand, the most difficult of the water use sectors to forecast, is expected to increase as more businesses are created in and around the city. Self-supplied domestic water use is assumed to remain the same over the next 50 years as some utilities expand to add service area in the unincorporated domains, and new homes are developed further away from the city. By the end of the forecast period, anticipated climate variation, due to changes in precipitation and temperature, could potentially add between 10 and 35 MGD of additional demand in the dry summer months. Again, this demand will be focused on the north side of the Region and to the south where growth is expected to continue.
County summaries of the water forecasts are provided in Tables ?? - ??. Phase III of the water study will utilize this water withdrawal forecast generated from this work and incorporate it into the water availability study.
|Commercial & Industrial||73.26||75.17||77.15||79.18||81.27||83.42||85.64||87.92||90.28||92.70||95.19|
|Irrigation & Agriculture||12.75||13.16||13.60||14.07||14.59||15.16||15.78||16.46||17.20||18.01||18.90|
|Public Water Supply||388.31||401.14||413.65||425.37||436.21||446.58||456.96||467.05||476.84||486.35||495.67|
|Public Water Supply||2.27||2.48||2.67||2.82||2.91||3.00||3.08||3.14||3.19||3.22||3.25|
|Commercial & Industrial||0.00||0.00||0.00||0.00||0.00||0.00||0.00||0.00||0.00||0.00||0.00|
|Irrigation & Agriculture||0.42||0.42||0.43||0.43||0.43||0.44||0.44||0.45||0.46||0.46||0.47|
|Public Water Supply||25.82||28.46||31.22||33.68||35.61||37.27||38.89||40.34||41.61||42.72||43.67|
|Commercial & Industrial||27.16||28.00||28.86||29.75||30.67||31.62||32.59||33.60||34.64||35.71||36.81|
|Irrigation & Agriculture||3.76||3.84||3.93||4.02||4.13||4.23||4.34||4.46||4.59||4.73||4.87|
|Public Water Supply||3.41||3.63||3.84||4.03||4.20||4.34||4.47||4.62||4.76||4.89||5.02|
|Commercial & Industrial||0.01||0.01||0.01||0.01||0.01||0.01||0.01||0.01||0.01||0.01||0.01|
|Irrigation & Agriculture||0.09||0.10||0.11||0.11||0.12||0.14||0.15||0.16||0.18||0.20||0.20|
|Public Water Supply||7.50||8.15||8.81||9.47||10.01||10.49||10.91||11.35||11.75||12.13||12.48|
|Commercial & Industrial||0.55||0.55||0.56||0.56||0.57||0.57||0.58||0.58||0.59||0.59||0.60|
|Irrigation & Agriculture||0.21||0.21||0.21||0.21||0.21||0.21||0.21||0.21||0.21||0.21||0.21|
|Public Water Supply||14.43||14.92||15.64||16.26||16.78||17.23||17.66||18.03||18.35||18.63||18.87|
|Commercial & Industrial||1.79||1.79||1.80||1.80||1.81||1.82||1.83||1.83||1.84||1.86||1.86|
|Irrigation & Agriculture||0.68||0.74||0.80||0.88||0.96||1.05||1.15||1.26||1.39||1.53||1.69|
|Public Water Supply||11.26||11.15||11.00||10.81||10.62||10.42||10.23||10.25||10.27||10.28||10.30|
|Commercial & Industrial||0.86||0.87||0.88||0.89||0.89||0.90||0.91||0.91||0.92||0.93||0.94|
|Irrigation & Agriculture||0.25||0.26||0.27||0.27||0.28||0.29||0.30||0.32||0.33||0.35||0.27|
|Public Water Supply||132.85||135.12||137.02||138.71||140.45||142.14||143.76||144.88||145.83||146.61||147.25|
|Commercial & Industrial||37.28||38.30||39.35||40.43||41.54||42.69||43.87||45.09||46.34||47.63||48.95|
|Irrigation & Agriculture||1.99||1.99||1.99||1.99||1.99||1.99||1.99||1.99||1.99||1.99||1.99|
|Public Water Supply||5.49||5.57||5.61||5.63||5.60||5.56||5.53||5.53||5.52||5.52||5.51|
|Commercial & Industrial||3.62||3.65||3.68||3.71||3.74||3.77||3.80||3.83||3.86||3.89||3.92|
|Irrigation & Agriculture||3.50||3.57||3.64||3.71||3.78||3.86||3.94||4.03||4.12||4.21||4.31|
|Public Water Supply||3.87||3.90||3.91||3.88||3.83||3.79||3.74||3.74||3.74||3.73||3.73|
|Commercial & Industrial||1.99||2.00||2.01||2.02||2.03||2.04||2.05||2.06||2.07||2.08||2.10|
|Irrigation & Agriculture||1.85||2.03||2.23||2.45||2.69||2.96||3.25||3.58||3.94||4.33||4.77|
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