Absence of wastewater and solid waste facilities impacts the quality of life of many people in developing countries. Implementation of these facilities will benefit public health, water quality, livelihoods and property value. Additional benefits may result from the potential recovery of valuable resources from wastewater and solid waste, such as compost, energy, phosphorus, plastics and paper. Improving water quality through implementation of wastewater and solid waste interventions requires, among others, an analysis of i) sources of pollution, ii) mitigating measures and resource recovery potentials and their effect on water quality and health, and iii) benefits and costs of interventions. We present an integrated approach to evaluate costs and benefits of domestic and industrial wastewater and solid waste interventions. To support a policy maker in formulating a cost and environmentally effective approach, we quantified the impact of these interventions on 1) water quality improvement, 2) resource recovery potential, and 3) monetized benefits versus costs. The integration of technical, hydrological, agronomical and socio-economic elements to derive these three tangible outputs in a joint approach is a novelty. The approach is demonstrated using the heavily polluted Indonesian Upper Citarum River in the Bandung region. Domestic interventions, applying simple (anaerobic filter) technologies, were economically most attractive with a benefit cost ratio (BCR) of 3.2, but could not reach target water quality standards. To approach the target water quality, both advanced domestic (nutrient removal systems) and industrial wastewater treatment interventions were required, leading to a BCR of 2. We showed that benefits from selling recovered resources represent here an additional driver for improving water quality and outweigh the additional costs for resource recovery facilities. While included benefits captured some of the major items, these may have been undervalued. Based on these findings, water quality interventions justify their costs and are socially and economically beneficial.
Nearly 40% of the population in developing countries lacks access to improved sanitation facilities [
First, discharge of untreated sewage can lead to adverse health effects on individuals [
Second, discharge of untreated wastewater increases nitrogen (N), phosphorus (P) and organic pollutants (Chemical oxygen demand (COD) and Biological Oxygen Demand (BOD)) loads to water bodies. This may result in eutrophication and low oxygen levels in waters, thus impacting ecosystem functioning [
Third, the value of recoverable resources from wastewater and solid waste, such as energy, water, organics, nutrients, plastic and paper is frequently neglected, whereas the sale of recovered resources can assure long-term operational and financial sustainability [
Finally, the absence of wastewater and solid waste facilities may accrue socio-economic impacts, such as travel and waiting time for community or public toilet facilities, loss of social capital and equity and decreased property values [
Thus, implementation of wastewater and solid waste interventions benefits public health, the environment, resource conservation, the economy and people’s welfare. However, given that implementation of interventions involves costs in the form of investments, operation and maintenance of the facilities, policy makers need to understand the outcomes (benefits) of major actions in relation to their costs [
Individual cause-effect relationships to evaluate the costs and benefits to improve water quality have been established, such as: 1) the effect of pollution load on the quality of receiving water [
The developed approach can be used on any river basin or delta. In this paper, the Upper Citarum River in West Java (Indonesia) is used as a case study because of its very low water quality combined with its impact on the life of millions of people downstream (see
To assess the impact of wastewater and solid waste interventions on water quality and estimate resource recovery and economic returns, the following six consecutive steps were formulated (
collected. This information was used as a baseline to determine the impact of different types of interventions. In step 2 the sources of pollution COD, BOD, N and P per sector (domestic, industrial and agricultural) were determined. An additional assessment on the relative contribution per sector was performed considering variations in the pollution load reaching the surface water with different urban areas [
Water quality data for COD, BOD, N and P for the period 2001-2009 in the upper Citarum River at Wangisagara, Sapan, Cijeruk, Dayeukholot and Nanjung (
Three sources of pollutions were distinguished and assessed for 2010 and 2030, being (A) Domestic, (B) Industrial and (C) Agricultural (
A. Domestic pollution:
Domestic pollution was determined in five steps.
1. Determination of specific per person pollution loads: Domestic specific water consumption rates followed the Indonesia guidelines [
2. Correction of pollution load with varying types of urban status: The relation between urban category and pollution loads was reflected using the study of [
A. Domestic per capita pollution loads reaching surface watera | B. Industrial concentrations in effluent per type of industry | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
Urban category | Water use | COD | BOD | TN | TP | Coliform | Type of industry | COD | BOD | TN | TP | |
l/cap/d | g/p/d | 1/100 ml | mg/l | |||||||||
1. Metropolitan | 190 | 82.2 | 41.1 | 12.3 | 2.1 | 1 × 108 | Food & Beverageb | 5000 | 3000 | 80 | 30 | |
2. Large town | 170 | 81.0 | 40.5 | 12.3 | 2.0 | 1 × 108 | Paperc | 4000 | 1500 | 20 | 10 | |
3. Medium town | 150 | 73.5 | 36.7 | 11.3 | 1.9 | 1 × 108 | Pharmaceuticald | 5000 | 1500 | 127 | 25 | |
4. Small town | 130 | 65.3 | 32.7 | 10.2 | 1.7 | 1 × 108 | Rubberd | 7340 | 4400 | 1100 | 220 | |
5. Village | 100 | 56.9 | 28.5 | 9.1 | 1.5 | 1 × 108 | Textilee | 1350 | 450 | 60 | 20 | |
6. Rural | 30 | 47.3 | 23.7 | 7.9 | 1.3 | 1 × 108 | Othersd | 280 | 168 | 42 | 8 | |
C. Agricultural pollution loads (g/Yield.ha)d | ||||||||||||
Type of crops | COD | BOD | TN | TP | Coliforms | |||||||
Rice | 45 | 22.5 | 21.5 | 6.5 | 0 | |||||||
Non-rice food crops | 34 | 17 | 4.6 | 0 | 0 | |||||||
a. Based on [
3. Correction of pollution reaching surface water bodies: Baseline pollution correction coefficients (included in
4. Determination of pollution loads reaching the surface water for 2010 and 2030: Total specific pollutions loads per location reaching the surface water were calculated applying the specific pollution loads (combining step 2 and 3 above) on population developments obtained from the Java Spatial Model (JSM). JSM shows the population development for each urban category between 2010 and 2030 [
5. Determination of the number of people with access to wastewater facilities in 2010: The pollution loads reaching the water bodies were corrected for interventions already in place. The 2010 wastewater access data were obtained from the statistical bureau of Indonesia (BPS) and were determined as 52%. 490,000 people were connected to the Bojong Soang WWTP (pond systems) in Bandung [
B. Industrial pollution:
838 industries in the catchment area were categorized by location and type (
C. Agricultural pollution:
The 2010 and 2030 water demand for irrigation was based on [
Domestic interventions:
Selection of type of domestic WWT facilities (
1. Simple Technology (ST): Anaerobic filter is applied for medium centralized systems and a conventional activated sludge (CAS) for centralized systems;
2. Advanced Technology (AT): Medium central and central systems apply a CAS with additional N, P removal;
Scenario | 1. % Removal efficiency | 2. % industries with WWTP per size of water intake (m3/d) | |||||||
---|---|---|---|---|---|---|---|---|---|
COD | BOD | TN | TP | 0 - 100 | 100 - 500 | 500 - 1000 | 1000 - 2000 | >2000 | |
Best case | 90 | 95 | 90 | 50 | 35 | 35 | 60 | 80 | 90 |
Baseline | 65 | 69 | 65 | 36 | 25 | 25 | 50 | 70 | 80 |
Worst case | 40 | 42 | 40 | 22 | 15 | 15 | 40 | 60 | 70 |
a.
System | Criteria for usea | Applied removal efficiencies per type of technology | ||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
Residential population density (pp/ha) | Status 2020b | COD (%) | BOD (%) | TN (%) | TP (%) | Coliforms (%) | ||||||
ST | AT/RR | ST | AT/RR | ST | AT/RR | ST | AT/RR | ST | AT/RR | |||
On-site | <100 | Rural/Urban | 40a | 45 | 15 | 5 | 90 | |||||
CBS | >100 | Rural | 80a | 85 | 15 | 5 | 99 | |||||
Medium Central | 100 - 250 | Urban | 80 | 88 | 85 | 97 | 15 | 90 | 5 | 67 | 99 | 99.9 |
Central | >250 | Urban | 88 | 97 | 73 | 29 | 99.9 |
a. Current users in urban areas with a residential density between 25 - 100 pp/ha apply on-site systems, whereas all new development will be served by medium centralized system [
3. Resource Recovery technology (RR): Comprising Aerobic Granular Sludge (AGS) system [
Associated investment and operational costs were based on [
Industrial interventions:
Three industrial wastewater treatment types were formulated based on currently applied technologies [
Municipal Solid Waste (MSW) interventions:
Solid waste system selection interventions (
A generic model package (RIBASIM) for simulating the behavior of river basins under various hydrological conditions was used to simulate the effect of different interventions on water quality development in the Upper Citarum River [
Type of area & Density Activity | Rural | Urban | ||
---|---|---|---|---|
<25 pp/ha | >25 pp/ha | <100 pp/ha | >100 pp/ha | |
Collection | no | yes | yes | |
Disposal | no | yes | yes | |
Level of 3R | Home composting | Decentralized composting and plastic/paper recovery | Central digestion and composting and plastic & paper recovery |
concentrations are calculated. The RIBASIM model and defined catchment areas are further explained in OSI Section 5. The pollution loads entering the Upper Citarum River were varied, using 6 scenarios (
The output of the 2010 RISBASIM average pollutant concentrations was calibrated based on the average measured concentration (step 1).
Five economic benefits of wastewater and solid waste management improvements were defined following [
A. Health:
Averted costs of fecal-oral disease from improved on-site sanitation and wastewater management: An average disease reduction of 36% by on-site sanitation and an additional 20% by adding improved off-site facilities was applied [
Associated averted health impacts (infectious diseases and skin complaints) of less exposure during flooding events: Reported health cases during a period of several flooding events (January-March 2009) were compared to the same period in a non-flood year (January to March 2010) and was scaled to reflect all the flooded communities in the Citarum River basin, resulting in an estimated 15,000 averted cases of diarrhea in an average year [
B. Access time:
Value of time savings from reduced travel time and/or queuing for meeting sanitation needs: An average daily gain of 115 minutes per household with an annual value of US $95 per household is used [
C. Water:
Reduced drinking water treatment costs to households and industries: The total cost of water treatment (including both capital and operating costs) using surface water of a better quality source will decrease from 0.13 to 0.06 US $/m3 [
Name | Description | |
---|---|---|
S1: Baseline | 2010: Baseline situation | |
S2: No intervention | 2030: Baseline case; same WWT access percentage as 2010 applied. Only correction for population growth for WWT and MSW | |
S3: | 25% ST | 2030: 100% Domestic access, use ST and 25% switch + 100% MSW |
25% AT | 2030: 100% Domestic access, use AT and 25% switch + 100% MSW | |
50% ST | 2030: 100% Domestic access, use ST and 50% switch + 100% MSW | |
50% AT | 2030: 100% Domestic access, use AT and 50% switch + 100% MSW | |
75% ST | 2030: 100% Domestic access, use ST and 75% switch + 100% MSW | |
75% AT | 2030: 100% Domestic access, use AT and 75% switch + 100% MSW | |
S4: Industrial only | 2030: Industrial WWT intervention; 100% of big (>1000 m3/d), 90% of medium (500 - 1000 m3/d), 80% small (100 - 500 m3/d), and 75% of very small (<100 m3/d) sized industries apply intervention. Domestic WWT, MSW interventions follow S2 | |
S5: 25% - 75% ST/AT | 2030: Combination of scenario 3 and 4 | |
S6a: 25% - 75% RR | 2030: Same as S5, using recovery technologies for domestic, industrial effluent recycling and MSW |
a: Except for S6, where a MSW resource recovery based system is applied, all other cases apply a conventional MSW system (no resource recovery).
multiplied by the assessed annual production of water from surface water sources (207 million m3 for domestic and 70 million m3 for industrial consumers) in 2030.
Improved fish yields from farming in downstream lakes due to improved water quality: Data collected through interviews with the regional Fisheries Office showed a decrease in fish catch of 5,000 ton/year in recent years [
D. Environment:
Reduced frequency of river and reservoir dredging due to improved sludge and waste management: An estimated 35 l/person/year of septic waste [
Rise in land prices due to improved aesthetics of riverside and lakeside real estate: Currently the Citarum riverside area is not developed due to water pollution. However, the area is expected to become a place where riverside property could be developed for inhabitants, small businesses, and tourist facilities in a situation where water quality is improved. The current agricultural land price (10.7 US $/m2) in the vicinity of Bandung was used as a benchmark for current riverside land prices. The current market suggests that land prices can climb to 71.3 US $/m2 in highly desirable locations [
Averted maintenance costs of hydro-electric facilities: Improved solid waste management would avert the current costs of US $0.1 million [
E. Recovery of resources:
In scenario 6, resource recovery was considered (see also
Off-site wastewater systems: Production of energy (sludge digestion), struvite (from centrate) and compost (digested sludge composting).
MSW: Energy and compost production from organic waste and recovery of plastics and paper.
Industrial wastewater: industries with a water consumption exceeding 2000 m3/d reused 80% of the effluent, whereas for industries using 1000 - 2000 m3/d this was 50%.
To compare the production (recovery) of resources with the potential demand in the Upper Citarum River catchment area in 2030, the compost, struvite, plastic and paper demand in the whole of West Java obtained from [
To relate benefits and costs to either wastewater or solid waste interventions, BCR’s were presented separately. To analyze the individual impact of domestic, industrial and resource recovery interventions the BCR of scenarios S3: (50% ST and S3: 50% AT), S4: (Industrial interventions only), S5: (50% ST; S5: 50% AT) and S6 (50% RR) were determined (see also
Current cumulative pollution loads in the Upper Citarum River basin of COD (585 tonne/d), BOD (264 tonne/d), TN (91 tonne/d) and TP (20 tonne/d) were determined as the baseline values (
The domestic pollution loads entering the Upper Citarum River depend on (1) the type of technology applied (simple versus advanced) and (2) the rate of current households applying on-site systems in urban areas that will switch to an off-site system (
Source | Scenario | COD (tonne/d) | BOD (tonne/d) | TN (tonne/d) | TP (tonne/d) |
---|---|---|---|---|---|
Domestic | Baseline loads | 388 | 188 | 68 | 12 |
100% reaches surface water | 440 | 213 | 78 | 14 | |
Half of baseline loads reach surface water | 194 | 94 | 34 | 6 | |
Industrial | Baseline | 163 | 60 | 6 | 2.6 |
Best case | 98 | 33 | 4 | 2.2 | |
Worst case | 215 | 80 | 8 | 3.0 | |
Agriculture | 34 | 17 | 16 | 5 | |
Total | Baselinea (S1) | 585 | 264 | 91 | 20 |
Minimumb | 325 | 144 | 54 | 13 | |
Maximumc | 688 | 310 | 103 | 22 |
a. Total baseline values comprise domestic and industrial baseline loads + agricultural loads; b. Total minimum values add domestic low pollution correction coefficient and Industrial best case + agricultural loads; c. Total maximum values add domestic high pollution correction coefficient and Industrial worst case + agricultural loads.
25% households switching to off-site systems leads to a 29% difference and a rate of 75% households switching to off-site systems leads to a 37% difference (
When increasing the switch factor from 25% to 75%, the additional removed COD and N increased with 5% and 1% for simple technologies and 6% and 9% for advanced technologies. BOD removal follows the COD trend, whereas P removal follows the N trend. Thus, the application of advanced technologies or a higher rate of people switching from on-site system to off-site systems mainly affects the additional nutrient removal, while organic removal is less affected. The numeric values of this analysis and further elaboration on costs of interventions and their impact on water quality are described in the OSI, Section 7.
The industrial pollution load amounts to 28% of the total load (
Figures 5(a)-(f) shows the effect of interventions on the year round average water quality at different locations. The location names are approximate locations, as RIBASIM calculates concentrations in defined segments of a river (see OSI,
additional interventions all concentrations will increase compared to the 2010 values (
To reach the desired water quality levels (class II) both industrial and domestic municipal interventions are needed. In addition, the applied off-site technologies should also include N and P removal, requiring more advanced and more costly technologies (see
The maximum quantified economic benefits are US $430 million per year in which health benefits account for 39% (
Convenience and time savings are among the top five reasons for having a latrine in the home area [
latrine facilities. This estimate is conservative as 1) it excludes travel needs for urination purposes, and 2) time is valued conservatively at 30% of the GDP per capita at hourly values.
US $13.9 million of the total US $23 million reduction in water treatment cost will accrue to the public water utilities and their consumers, while industries are expected to benefit US $4.7 million annually. The value of farmed fish yields is expected to be US $4 million annually.
The combined environmental benefits (increased land value, reduced dredging, averted maintenance costs of hydro-electric facilities) amount to US $17 million, of which nearly 90% is attributed to increases in land value based on annual land sales. The benefits of reduced dredging (even assuming no decomposition or organic waste) have minor benefits.
Following the anticipated benefits (
Parameter | Recoverable resources per sector and potential demand | Total revenues (million US $/year) | ||||||
---|---|---|---|---|---|---|---|---|
Domestic WWT | Industrial WWT | MSW | Total recovery | Potential demand | Unit | Recovery percentage | ||
Compost | 91 | - | 351 | 442 | 1240 | ktonne/y | 36% | 44.2 |
Plastic | - | - | 228 | 228 | 366 | ktonne/y | 62% | 45.5 |
Paper | - | - | 193 | 193 | 1185 | ktonne/y | 16% | 38.6 |
Electricity | 27 | - | 89 | 116 | 78.8 | GWh/y | 147% | 11.6 |
Water | - | 43 | - | 43 | 563 | Mm3/y | 8% | 2.6 |
Struvite | 4.2 | - | - | 4.2 | 35 | ktonne/y | 12% | 4.1 |
Total economic value | 146.6 |
tackling both domestic and industrial pollution results in a BCR ranging from 1.83 (S5: 50% AT) to 2.64 (S5: 50% ST). However, simple technologies were not found sufficient to improve the water quality to levels approaching class II, especially in terms of nutrient (N, P) removal (
The economic returns on combined wastewater and solid waste interventions are lower than the returns on wastewater interventions only (
Additional benefits of resource recovery from MSW can be a driver for improving water quality. The BCR (including MSW) of scenario 5 (applying AT) is 1.19 and will increase to 1.65 by applying resource recovery (
Category | Sub category | A. WWT costs and benefits | B. WWT and MSW costs and benefits | ||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|
S3: 50%_ST | S3: 50%_AT | S4: industrial only | S5: 50%_ST | S5: 50%_AT | S6: 50%_RR | S3: 50%_ST | S3: 50%_AT | S4: Industrial only | S5: 50%_ST | S5: 50%_AT | S6: 50%_RR | ||
BCR | Baseline BCR | 3.20 | 2.06 | 0.52 | 2.64 | 1.83 | 1.85 | 1.62 | 1.26 | 0.52 | 1.49 | 1.19 | 1.65 |
Resource prices 50% of baseline | 3.20 | 2.06 | 0.52 | 2.64 | 1.83 | 1.79 | 1.62 | 1.26 | 0.52 | 1.49 | 1.19 | 1.37 | |
Health impact 50% of baseline | 2.22 | 1.42 | 0.52 | 1.86 | 1.29 | 1.34 | 1.12 | 0.87 | 0.52 | 1.05 | 0.84 | 1.33 | |
40 year capital lifespan | 4.94 | 3.01 | 0.60 | 3.80 | 2.58 | 2.61 | 2.11 | 1.65 | 0.60 | 1.91 | 1.54 | 2.18 | |
15 year capital lifespan | 2.60 | 1.70 | 0.48 | 2.19 | 1.53 | 1.55 | 1.40 | 1.09 | 0.48 | 1.29 | 1.03 | 1.42 | |
Access time gained 50% of baseline | 2.75 | 1.76 | 0.52 | 2.28 | 1.58 | 1.61 | 1.39 | 1.08 | 0.52 | 1.28 | 1.03 | 1.50 |
weigh the benefits by a small margin.
In case recovered resources are sold at only half the current market price (
Evaluating the economic performance of wastewater and solid waste interventions is a complex process, involving many variables and alternative combinations and coverage levels of interventions. Therefore a methodology was developed that combines several assessment methods and data sources in order to support decision making. The added value of the integrated approach allows for a nuanced view on interrelations compared to single cause-effect relations [
The practical application of the integrated approach is first demonstrated in the analysis of contribution of pollution per sector (industry, domestic or agriculture) related to the pollution prevention costs. The large contribution of domestic pollution was unambiguous and confirmed in a sensitivity analysis (see also OSI, Section 7). Presented results are in line with findings of [
Secondly, the integrated approach supports determination of cost-effective interventions. The added value of applying more advanced technologies or switching more people to a sewer system showed that required additional investments can be justified from the point of nutrient removal, but less so from COD removal (
Thirdly, linking the resource recovery potential and its revenues to its potential demand may benefit formulation of policies or increase government involvement to foster financial sustainability of sanitation facilities [
Fourthly, monetizing both direct use and indirect non-use values of sanitation implementation in relation to achievable surface water quality enables the formulation of a cost and environmental effective approach. The performed analysis demonstrated that the most cost effective scenario (S3: 50%_ST) with the highest BCR differs from the scenario reaching the required water quality (e.g. S5: 50%_AT). Therefore, a policy maker needs to prioritize between these two options. As a cost effective strategy, application of advanced technologies may be restricted to the most highly densely populated urban areas (where most pollution is produced). Alternatively, a phased approach in which first simple (low cost) technologies are implemented that are later replaced, converted or extended by systems that allow for nutrient removal [
The outcomes of the study were formulated in a planning document for the Indonesian government [
The presented framework can be further extended given the following considerations:
To assess the sustainability of interventions and ensure that pollution is being removed and not displaced, environmental emissions other than water pollution (COD, N, P), such as odor or greenhouse gasses may be included. The effect of greenhouse gasses emitted by low cost technologies (e.g. anaerobic filters or septic tanks) is excluded from the current evaluation.
In the determination of the water quality, several assumptions were made that may affect obtained results and could be incorporated in a next phase (see also OSI Section 9). First, a connection between surface and ground water was assumed in which infiltrated septic tank effluent load directly influences the surface water quality. Second, RIBASIM model disregards biological conversion of pollutants in the surface water, whereas these are observed in the field [
The low BCR of industrial interventions (0.52,
Aerobic technologies were used as industrial references, whereas the use of anaerobic technologies may result in lower investment and/or operational costs [
Not all economic impacts were quantified in this study (see also OSI, Section 10), such as consumption of fish imbibing toxic wastes or otherwise infected [
Applying advanced technologies (AT) will improve water quality (
The BCR considers the overall societal perspective, whereas different costs and benefits are incurred and enjoyed by different stakeholders. Thus, the costs of domestic interventions are to a large extent paid for by the national and local governments (in Indonesia ~ 70%) and to lesser extent by individual households [
In this study, an integrated method was presented that quantified the economic costs and benefits of wastewater and solid waste interventions in relation to water quality improvements and resource recovery potential. The approach provides added value in the decision making process in a complex and dynamic context since it helps resolve trade-offs across different dimensions of sustainability (e.g. social, environmental and economic).
Identification of pollution sources and the impact of interventions on discharged pollution loads allows for prioritizing of actions. By simultaneously modeling the water quality and cost impact of variations in 1) type of technology and 2) the household numbers switching from poor-performing septic tanks to off-site systems, insight into the cost-effectiveness of environmental policies is provided. This allows a policy maker to optimize economic and water quality benefits.
In the presented case of the Upper Citarum River, domestic interventions applying simple technologies were most attractive, with an estimated BCR of 3.2. However, to achieve the target water quality both industrial and advanced domestic WWT technologies would be required, leading to an estimated BCR of 2.0. Resource recovery from MSW was found to be a driver for improving water quality, as benefits through the sale of recovered resource outweighed the additional costs to improve the water quality.
The authors acknowledge the contribution of Aart van Nes, Fery Hardianto and Wil van der Krogt in the data collection and RIBASIM modeling as part of the 6 Ci’s project funded by the ADB (TA7189-INO: Institutional Strengthening for Integrated Water Resources Management (IWRM) in the 6 Ci’s River Basin Territory-Package B). The economic works of this study was funded by WSP’s Multi-Donor Trust Fund for WSP East Asia and the Pacific, supported by the Government of Australia. Guy Hutton conducted the work while employed at the World Bank. We thank Isabel Blackett, Almud Weitz, Enrico Rahadi Djonoputro, and Deviariandy Setiawan for their valuable input. In loving memory of pak Nugroho-Director of Urban, Housings and Settlements, National Development Planning Agency (Bappenas); may you rest in peace.
Kerstens, S.M., Hutton, G., Firmansyah, I., Leusbrock, I. and Zeeman, G. (2016) An Integrated Approach to Evaluate Benefits and Costs of Wastewater and Solid Waste Management to Improve the Living Environment: The Citarum River in West Java, Indonesia. Journal of Environmental Protection, 7, 1439-1465. http://dx.doi.org/10.4236/jep.2016.711122