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Ghana Priorities: Fecal Treatment and Reuse

In Ghana, the prevalence of onsite sanitation is more than 85%. This means that when the receptacles containing the faecal sludge are full they have to be collected and treated before discharging into the environment. Unfortunately, there are very few treatment plants available in the country and fecal sludge is mostly dumped into water bodies, drains, trenches, farms, bushes, and other unauthorized places.

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Ghana Priorities: Fecal Treatment and Reuse

  1. 1. EminentPanelConference,Accra,August7th -9th,2020 COST-BENEFIT ANALYSIS OF FAECAL SLUDGE MANAGEMENT IN GHANA Esi Awuaha, Ahmed Issahakua, Martha Osei-Marfob, Sampson Oduro Kwartenga, Micheal Addo Aziatsia and Copenhagen Consensus. a(Dept. of Civil Engineering, KNUST) b(Dept. of Water and Sanitation, UCC)
  2. 2. Faecal Sludge characteristics • Human excreta production 130-450g of excreta daily and 1.4L of urine everyday • Major source of pathogens viruses, bacteria, protozoans and helminths • Source of nutrients –Nitrogen, Phosphorous etc • Source of Energy in the form of organic carbon • The pathogens calls for treatment before its application and use • Calling for proper handling and management of excreta leading to now what we will call sanitation Sanitation is basically the protection of a community from diseases associated with poor waste management practices and the improvement in the overall environmental quality.
  3. 3. Background information Accra(years back) Nungua Farms Dumpsite Tamale Cape coast
  4. 4. Volta Region Takoradi Koforidua Background information Dompoase - Kumasi
  5. 5. Problems Associated with Poor Faecal Sludge Management • About 85% of onsite sanitation toilet technologies in Ghana. • This leads to improper dumping of the waste leading to rapid transmission of diseases. • 88% of diarrhea diseases in Accra due to Sanitation • 41million cases of Diarrhea in 2017 nation wide • The diseases due to poor sanitation including improper disposal of faecal sludge is 290million dollars. • 1.6% of GDP
  6. 6. DESCRIPTION OF FAECAL SLUDGE TREATMENT TECHNOLOGIES 2. Comprehensive treatment plant 3. Faecal sludge treatment biogas to electricity plant at Lavender Hill in Accra 4. Sludge biomass to electricity 1. Waste Stabilization ponds
  7. 7. COMPREHENSIVE FAECAL SLUDGE TREATMENT PLANTS (Intervention 1)
  8. 8. Comprehensive Waste treatment plant at Lavender Hill
  9. 9. Comprehensive treatment plants would cost 1,349m cedis with CAPEX costs of 642m cedis Total Costs = 1,349m cedis Capex costs = 642m cedis • 9.1m cedis fixed cost per plant • 82,000 cedis per m3 daily treatment capacity • 280m3 average daily treatment req per plant • 3.2m cedis fixed cost for 2km access road per plant Opex and enforcement costs = 101m cedis in year 1 • 12% of capex (based on study from Dakar, Senegal) • 24% of capex for those near coast • 40% increased enforcement capacity Estimated lifespan of each plant • Ideal scenario: 15 years if properly maintained • Realistic scenario: Only 50% of plants are still operating after 10 years. This accounts for: • Technical, financial and other maintenance issues that prevent continued operations • Lack of compliance with sanitation laws and indiscriminate dumping of sludge - 100,000,000 200,000,000 300,000,000 400,000,000 500,000,000 600,000,000 700,000,000 2019 2020 2021 2022 2023 2024 2025 2026 2027 2028 2029 2030 2031 2032 2033 2034 2035 2036 GHS Costs of comprehensive treatment plants Capex Costs Opex Costs
  10. 10. Intervention will avoid 329 deaths and 1.9m cases of diarrhea in the first year Benefits = 3962m cedis Health benefits • Assume faecal sludge treatment can maximally reduce diarrheal disease by 30% • Estimation inferred from meta-analyses and a study on pathogen transmission in Accra though evidence is limited • Leads to 329 deaths and 1.9 m cases of diarrhea avoided initially, decreasing in line with plant failure • This effect size is tempered by reported regional estimates of i) sewer coverage and ii) open defecation • FST cannot influence pathogens that are already transmitted via sewer or that are defecated direct into the environment • Largest effect size is in Ashanti (26%), lowest effect size is Upper East (10%) Other benefits • Does NOT include other potential benefits from cleaner environment including tourism, lack of smell, improved biodiversity - 100,000,000 200,000,000 300,000,000 400,000,000 500,000,000 600,000,000 2019 2020 2021 2022 2023 2024 2025 2026 2027 2028 2029 2030 2031 2032 2033 2034 2035 2036 Benefits Initial decrease due to plant failure Later increase due increase in value of life years in line with GDP
  11. 11. BCR of comprehensive treatment plants is 2.9 Intervention Benefits (millions cedis) Costs (millions cedis) BCR Comprehensive treatment plants across Ghana 3962 1349 2.9
  12. 12. Comprehensive FST targeted areas • The areas targeted for this intervention are Tema Metropolis, Cape Coast metropolis, Effutu Municipal, Adansi North, Kumasi Metropolis, Sunyani Municipal, New Juaben Municipal, Tamale Metropolis, Sekondi/Takoradi Metropolis, Bolgatanga, Wa, Ho Municipal, Bunkprugo-Yunyoo, Nkwanta South, Sawla-Tuna-Kalba, Asunafo North, Sefwi Wiaso and Techiman Municipal. All the sixteen regions in Ghana were considered. (18 areas) • Cumulatively, a total of about 6.8 million people will be reached by the intervention.
  13. 13. ENERGY/RESOURCE RECOVERY SYSTEMS (Intervention 2)
  14. 14. Biogas to Energy (Electricity) Costs = 1579m cedis Capex costs = 784m cedis • 7.8m cedis fixed cost per plant • 27,000 cedis per m3 daily treatment capacity • 200m3 average daily treatment req per plant • 3.2m cedis fixed cost for 2km access road per plant Opex and enforcement costs = 115m cedis p.a. in year 1 • 12% of capex (based on study from Dakar, Senegal) • 24% of capex for those near coast • 40% increase in enforcement capacity Estimated lifespan of each plant • Ideal scenario: 15 years if properly maintained • Realistic scenario: Only 50% of plants are still operating after 10 years. Benefits = 7485m cedis Health benefits • Assume faecal sludge treatment can maximally reduce diarrheal disease by 30% • Leads to 591 deaths and 3.8m cases of diarrhea avoided initially, decreasing at the same rate as plant failure Resource recovery benefits • 48,000 kWh produced per year • 1.3 cedis per kWh economic benefit (based on Ghanaian study) • Very minor contribution, <1% of benefits Other benefits • Does NOT include other potential benefits from cleaner environment including tourism, lack of smell, improved biodiversity
  15. 15. Sludge to Energy (Electricity) Costs = 1395m cedis Capex costs = 688m cedis • 7.8m cedis fixed cost per plant • 18,000 cedis per m3 daily treatment capacity • 200m3 average daily treatment req per plant • 3.2m cedis fixed cost for 2km access road per plant Opex costs = 102m cedis in year 1 • 12% of capex (based on study from Dakar, Senegal) • 24% of capex for those near coast • 40% increase in enforcement capacity Estimated lifespan of each plant • Ideal scenario: 15 years if properly maintained • Realistic scenario: Only 50% of plants are still operating after 10 years. Benefits = 7451 m cedis Health benefits • Assume faecal sludge treatment can maximally reduce diarrheal disease by 30% • Leads to 591 deaths and 3.8 m cases of diarrhea avoided initially, decreasing at the same rate as plant failure Resource recovery benefits • Very minor contribution, <1% of benefits Other benefits • Does NOT include other potential benefits from cleaner environment including tourism, lack of smell, improved biodiversity
  16. 16. BCR of Energy/Resource Recovery Systems Intervention Benefits (millions cedis) Costs (millions cedis) BCR Biogas to Energy 7485m 1579m 4.7 Sludge to Energy 7451m 1395m 5.3
  17. 17. Sludge to Electricity Target areas • The areas targeted for this intervention are Tema Metropolis, Cape coast metropolis, Effutu Municipal, Adansi North, Kumasi Metropolis, Sunyani Municipal, New Juaben Municipal, Tamale Metropolis, Sekondi/Takoradi Metropolis, Bolgatanga, Wa, Ho Municipal, Bunkprugo-Yunyoo, Nkwanta South, Sawla-Tuna-Kalba, Asunafo North, Sefwi Wiaso, Techiman Municipal, Ada west, Ashaiman Municipal, Agona west Municipal, Ajumako-Enyan-Essiam, Assin Central, Twifo-Heman- Lower Denkyira, Asokore Mampong, Atwima Kwanwoma, Mampong Municipal, Sekyere Central, Berekum Municipal, Dormaa Central Municipal, Jaman North, Birim North, Birim Central Municipal, Fanteakwa, Karaga, Nanumba North, Sagnerigu Municipal, Yendi, Ahanta West, Nzema East, Wassa Amenfi West, Bawku, Garu Tempane, Talensi, Jirapa, Lawra, Sissala East Akatsi south, ketu south North Tongu, Chereponi Mamprusi East,Biakoye, Krachi East, Bole Gonja Central Asutifi South, Tano North, Aowin, Bia west, Sefwi Bibiani-Ahwiaso Bekwai, Atebubu Amantin, Kintampo North Municipal, Pru and Nkoranza South. All the sixteen regions in Ghana were considered. (64 areas) • Cumulatively, a total of about 14 million people would be reached by the intervention in the country.
  18. 18. STABILIZATION PONDS (Intervention 3)
  19. 19. Stabilization ponds across Ghana would cost 926m cedi with capex costs of 436m cedis Costs = 926m cedis Capex costs = 436m cedis • 2.3m cedis fixed cost per pond • 34,000 cedis per m3 daily treatment capacity • 120m3 average daily treatment req per pond • 3.2m cedis fixed cost for 2km access road per pond Opex and enforcement costs = 59m cedis in year 1 • 12% of capex (based on study from Dakar, Senegal) • 24% of capex for those near coast • 40% increase in enforcement capacity Estimated lifespan of each pond • Ideal scenario: 15 years if properly maintained • Realistic scenario: Only 75% of ponds are still operating after 5 years. This accounts for: • Technical, financial and other maintenance issues that prevent continued operations • Lack of compliance with sanitation laws and indiscriminate dumping of sludge - 50,000,000 100,000,000 150,000,000 200,000,000 250,000,000 300,000,000 350,000,000 400,000,000 450,000,000 500,000,000 2019 2020 2021 2022 2023 2024 2025 2026 2027 2028 2029 2030 2031 2032 2033 2034 2035 2036 GHS Costs of stabilization ponds Capex Costs Opex Costs
  20. 20. - 100,000,000 200,000,000 300,000,000 400,000,000 500,000,000 600,000,000 700,000,000 Benefits Intervention will avoid 263 deaths and 1.9m cases of diarrhea in the first year Benefits = 4113m cedis Health benefits • Assume faecal sludge treatment can maximally reduce diarrheal disease by 30% • Estimation inferred from meta-analyses and a study on pathogen transmission in Accra though evidence is limited • Leads to 263 deaths and 1.9m cases of diarrhea avoided initially, decreasing in line with plant failure • This effect size is tempered by reported regional estimates of i) sewer coverage and ii) open defecation • FST cannot influence pathogens that are already transmitted via sewer or that are defecated direct into the environment • Largest effect size is in Ashanti (26%), lowest effect size is Upper East (10%) Other benefits • Does NOT include other potential benefits from cleaner environment including tourism, lack of smell, improved biodiversity Benefits increase as value of mortality risk reduction increases with GDP growth
  21. 21. Targeted areas for Waste stabilization ponds • Ada West, Ashiaman Municipal, Agona West Municipal, Ajumako-Eryan-Essiam, Assin Central, Twifo-Heman-Lower Denkyira, Asokore Mampon, Atwoma Kwanwoma, Mampong Municipal, Sekyere central, Berekum Municipal, Dormaa central Municipal, Jaman North, Birim North, Birim Municipal, Fanteakwa, Karaga, Nanumba north, Sagnerigu Municipal, Yendi, Ahanta West, Nzema East, Wassa Amenfi West, Bawku, Garu Tempane, Talensi, Jirapa, Lawra, Sissala East Akatsi south, ketu south North Tongu, Chereponi Mamprusi East,Biakoye, Krachi East, Bole Gonja Central Asutifi South, Tano North, Aowin, Bia west, Sefwi Bibiani-Ahwiaso Bekwai, Atebubu Amantin, Kintampo North Municipal, Pru and Nkoranza South. All the sixteen regions in Ghana were considered. (46 areas) • Cumulatively, a total of about 7.1 million people would be reached by the intervention in the country.
  22. 22. BCR of stabilization pond is 4.4 across all Ghana Intervention Benefits (millions cedis) Costs (millions cedis) BCR Stabilization ponds across all Ghana 4113m 926m 4.4
  23. 23. BCR Summary of Faecal sludge interventions Intervention Benefits (millions cedis) Costs (millions cedis) BCR Comprehensive treatment plants 3962m 1349m 2.9 Biogas to energy plants 7485m 1579m 4.7 Sludge to energy plants 7451m 1395m 5.3 Stabilization ponds 4113m 926m 4.4 Notes • All interventions pass benefit-cost test but overall evidence base is limited • Evidence on diarrhea benefits is very limited, 30% reduction as a maximum benefit seems reasonable but no studies to date confirm this with high certainty • Evidence of failure rates across time are also limited -> affects long term costs and benefits
  24. 24. Intervention Areas 1. Comprehensive treatment plants, BCR = 2.9 - Urban district capitals across Ghana - Targeting 18 sites across Ghana with 6.8m population served 2. Resource recovery plants (sludge to electricity, biogas to electricity), BCR = 4.7 to 5.3 - Can be placed in peri-urban or urban sites - Targeting 64 sites across Ghana with 14 million population served 3. Stabilization ponds, BCR = 4.4 - Peri-urban sites across Ghana with enough land availability - Targeting 46 sites across Ghana with 7.1 population served
  25. 25. Conclusion • Irrespective of the intervention used, the returns are positive
  26. 26. Sensitivity Analysis BCR for Comprehensive BCR for Stabilization Pond BCR for Biogas to energy BCR for Sludge to Energy Central 2.9 4.4 4.7 5.3 No failure 3.4 4.8 5.5 6.2 Failure is twice as fast and large 2.5 3.7 4.0 4.5 Diarrhea impact +50% 4.4 6.7 7.1 8.0 Diarrhea impact -50% 1.5 2.2 2.4 2.7 Costs +25% 2.3 3.6 3.8 4.3 Costs -25% 3.9 5.9 6.3 7.1
  27. 27. Recommendations • The Environmental Impact Assessment should be considered before implementation. • More detailed site specific studies to ascertain more precise benefits to costs before project implementation. • Plants when installed should be managed by Public Private Partnership and paid based on performance contract. • The Assemblies and regulatory bodies should ensure that this is done. • Plan for Land acquisition for treatment plants should be done as a matter of urgency • More research studies on current treatment facilities is needed to assess the real economic benefits
  28. 28. Thank You

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