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Definition of the indicator
This indicator defines the quantity of sludge per day that the facility can receive according to the design. Unit/value: m3/day

How to measure or calculate it
Review the design documents or ask to the design team or consultant: the input flow is considered to design the faecal sludge treatment plant. It is based on the design population, knowing that an average individual produces between 0.12 – 0.40 litres of faeces and 0.6 – 1.5 litres of urine per day. For small networks (small bore sewerage, solids free sewerage) where domestic drinking water network is available: it is estimated that 80% of the drinking water supply ends up in the sanitation system.

Why is it important to measure it
This indicator is important to know what inlet flow the plant can receive (mean and maximum). It is used to design the whole facility (tanks, pumps, drying beds, etc.).”

Definition of the indicator
Chemical Oxygen Demand (COD) is a way to measure how many pollutants from organic materials are present in wastewater, faecal sludge, effluent, or other streams. It measures how much oxygen is used up to break down organic pollutants.

Why is it important to measure it
The COD is one of the design and performance parameters for (faecal sludge) treatment plants and one of the regulatory standards for effluent discharge. COD is typically expressed as milligrams per litre (mg/L) or grams per litre (g/L).

Definition of the indicator
Total Solids (TS) is a measure of the total amount of organic and inorganic solids and is determined by evaporating a known volume of water.

It is one of the design and performance parameters for (faecal sludge) treatment plants. TS is typically expressed as milligrams per litre (mg/L) or grams per litre (g/L).

Definition of the indicator
Number of people to benefit from the faecal sludge treatment service that was used for the design of the treatment plant.

How to measure or calculate it Analyse the current population, its growth and movement trends. In a stable growing population, population to be served can be calculated as follows:
Pn = P0 * (1+i)^n
Pn = Population in year ‘n’
n = design period (refer to design life indicator) P0 = Population in year 0
i = annual growth of the population
However in humanitarian context, this will usually depend on the security context (forecast of the population affected by the crisis).

References, tips, examples n = design period = 5 years
P0 = Population in year 0 = 1,000 persons
i = annual growth of the population = 10% influx per year
P5 = 1,000 * (1+0.1)^5 = 1,610 persons, say 1,600

Why is it important to measure it It is necessary to know the size of the population that needs to be served in order to design the treatment plant correctly and accordingly. It is important to forecast the population growth to better size the facility (tanks, pumps, drying beds, etc.) so that it can answer to the future needs of the population. If the facilities are not designed according to the needs, the construction and operation costs can end up being unnecessarily increased (plant overdesigned) or the treatment results can be poorer (plant underdesigned).

Definition of the indicator
This is the space occupied by the faecal sludge treatment site in relationship with the design input flow (see indicator).

How to measure or calculate it
Measure in the field (on site) or in the project designs, the total area of the faecal sludge treatment site and divide it by the designinput flow (see indicator).

Example:
If the total area of the plant is 500 m2, and the design input flow is 100m3, the required space is 500/100= 5m2/ m3.

Why is it important to measure it
This indicator is useful to know the amount of land needed to implement treatment technologies depending on the quantity of sludge generated. In humanitarian contexts, where the population is often obliged to settle in crowded areas with unfavourable environmental conditions, the space available for faecal sludge treatment sites may be limited.

Definition of the indicator This indicator defines the total cost the construction works, including:
– Preliminary and general items (Office and transport contractor and supervisors, security, insurance, electricity supply connection, etc.)
– Purchase of land if relevant
– Civil works
– Electromechanical works: pumps, GenSet, etc.
– Design (typically 5% of Civil & Electromechanical costs)
– Supervision of implementation (typically 5-15% of Civil and Electromechanical costs) divided by the design input flow.

How to measure or calculate it
Review the purchase documents and include the HR costs related to construction. All the expenditure for the construction and installation of a sludge faecal treatment system has to be considered and divided by the design flow (see indicator).

References, tips, examples
Capital expenditure per design flow for faecal sludge treatment sites differs from place to place and depends mostly on transport costs. A treatment plant in inaccessible areas where cement bags need to be flown in can be 10 times more expensive than the same plant in areas where cement can be purchased ‘off the shelf’.

Why is it important to measure it
This indicator is useful to know the cost of construction of a treatment solution, in relation to the volume of sludge treated. This enters in the decision-making process to choose a treatment solution as the amount of money available for construction can be limited.

Definition of the indicator
This indicator is required to know how much sludge is currently treated at the faecal sludge treatment site. It can differ from the design flow and be lower.

How to measure or calculate it
Calculate the real input flow by measuring the sludge volume in transport tanks arriving to the faecal sludge treatment site or by measuring the pump flow rates and their time of use (duration of usage) during desludging. Consider an average value including also the days the faecal sludge treatment activities are not running. If it’s not possible to measure in the field, the input flow is estimated as follows:
For emergency simple pits where effluent can infiltrate and latrines are emptied at regular intervals consider the following sludge accumulation rates:
– Wastes retained in water where water is used as anal cleansing material: 25 litres per capita per year (lcy);
– Wastes retained in water where degradable anal cleansing materials are used: 40lcy;
– Wastes retained in water where non-degradable anal cleansing materials are used: 60lcy;
– Wastes retained in dry conditions where degradable anal cleansing materials are used: 60lcy;
– Wastes retained in dry conditions where non-degradable anal cleansing materials are used: 90lcy.
For pour-flush facilities where water cannot infiltrate and be emptied at regular intervals: it is estimated at 4.2 lcd (2 for additional flush water),
For small networks (small bore sewerage, solids free sewerage) where domestic drinking water network is available: it is estimated that 80% of the drinking water supply ends up in the sanitation system.

Examples: Simple pit latrines emptied at regular intervals and with poor pit infiltration: only water used for anal cleansing and cleaning the toilet enters the receptacle together with the volume of urine and faeces. Typical volume for anal cleansing is 1 litre per person per day (lcd or litres per capita per day).
Typical volume of fresh urine and faeces is 1.2 lcd. Hence, for 1.000 people: 1.000 * (1+1.2) = 2,200 litres or 2.2 m3/day;
Pour-flush facility where water cannot infiltrate, emptied at regular intervals: water used for anal cleansing and for manually flushing the toilet enters the receptacle. A typical volume for pour-flush is 2-3 lcd. Hence, for 1,000 people: 1,000 * (3+1.2) = 4,200 litres or 4.2 m3/day;
Small network (small bore sewerage, solids free sewerage) where domestic drinking water network is available: when wastewater is collected, conveyed and treated, usually 80% of the drinking water supply ends up in the system. Hence, if for example drinking water is 25lcd, wastewater is 25 * 0.8 = 20lcd. Hence, for 1,000 people: 1,000 * 20 = 20,000 litres or 20 m3/day.

Why is it important to measure it
The real input flow can be compared with the design flow and upgrades or flow increases can be planned accordingly.

Definition of the indicator
Total solids is the measurement of the concentration of particulate solids that can dissolve or suspend in wastewater. It is commonly expressed as mass of solids in comparison to volume of solution (% weight-volume).
The reduction is related to the total solids concentration of the effluent exiting the faecal sludge treatment site in comparison to the total solids concentration of the influent entering the faecal sludge treatment site.

How to measure or calculate it
The reduction is calculated as a relative percentage of the average total solids value of the effluent exiting the faecal sludge treatment site over the average total solids value of the influent entering the faecal sludge treatment site in the same period.
% = (1-Ce/Ci) x 100
with Ce = effluent TS concentration (mg/l)
Ci = influent TS concentration (mg/l)
The laboratory test protocol can be found at:
The STeP Global Testing Protocols & Parameters
– A best practices guide for testing sanitation technologies in the field http://stepsforsanitation.org/?smd_process_download=1&download_id=4171

References, tips, examples
Septage (contents of a septic tank) usually has a low percentage of solids (typically 1-2 %) and faecal sludge from pit latrines usually has a high percentage of solids (typically 10-15%). Example values from Zambia: 7-15% for pit latrines and 1-2% for septic tanks.
For example if the influent TS concentration of the treatment plant is 1000 mg/l and the effluent TS concentration is 400 mg/l:
(1-400/1000) x 100 = 60% of TS reduction.

Why is it important to measure it
Faecal sludge characteristics vary widely between cities, types of on-site sanitation systems and types of emptying system used. Samples taken from the same pit latrine can have significant variations in standard physio-chemical testing, which impacts how sludge must be treated.
Suspended solid can lead to the development of sludge deposits and anaerobic conditions when untreated wastewater is discharged in the aquatic environment.
Moreover, as an example, solids content is an important parameter to estimate the volume of dried sludge to be removed from the drying beds of sludge treatment plants.

Definition of the indicator
Chemical oxygen demand (COD) is an indicative measure of the amount of oxygen that can be consumed by reactions in a measured solution. It is commonly expressed in mass of oxygen consumed over volume of solution (mg/L) and is composed principally of proteins, carbohydrates and fats.
The reduction is related to the COD concentration of the effluent exiting the faecal sludge treatment site in comparison to the COD concentration of the influent entering the faecal sludge treatment site.

How to measure or calculate it
The reduction is calculated as a relative percentage of the average COD value of the effluent exiting the faecal sludge treatment site over the average COD value of the influent entering the faecal sludge treatment site in the same period.
% = (1-Ce/Ci) x 100
with Ce = effluent COD concentration (mg/l)
Ci = influent COD concentration (mg/l)
The laboratory test protocol can be found at:
The STeP Global Testing Protocols & Parameters
– A best practices guide for testing sanitation technologies in the field http://stepsforsanitation.org/?smd_process_download=1&download_id=4171

References, tips, examples
If the influent COD concentration of the treatment plant is 3000 mg/l and the effluent COD concentration is 1000 mg/l: (1-1000/3000) x 100 = 66% of COD reduction.
Influent values example from Zambia: 50,000-100,000mg/l for pit latrines and 10,000-20,000mg/l for septic tanks

Why is it important to measure it
Faecal sludge characteristics vary widely between cities, types of on-site sanitation systems and types of emptying system used. Samples taken from the same pit latrine can have significant variations in standard physio-chemical testing, which impacts how sludge must be treated.
The COD parameter monitors the available oxygen which has a direct impact on aquatic life. If biodegradable organics are discharged untreated to the environment, their biological stabilisation can lead to the depletion of natural oxygen resources and to the development of septic conditions.

Definition of the indicator
Faecal coliforms are pathogenic organisms that can transmit diseases. They include genera that originate in feces (e.g. Escherichia) as well as genera not of faecal origin (e.g. Enterobacter, Klebsiella, Citrobacter). It is an indicator of faecal contamination, indicating the presence of other pathogens. E.Coli are part of the feacal coliforms that can be tested. They are commonly expressed in colony forming units over 100mL volume of solution (CFU/100mL), or in Log (1 log = 1000 CFU/100mL).
The reduction is related to the faecal coliforms concentration of the effluent exiting the faecal sludge treatment site in comparison to the faecal coliforms concentration of the influent entering the faecal sludge treatment site.

How to measure or calculate it
The reduction is calculated as COMPLEMENTARY PERCENTAGE of the average faecal coliforms of effluent exiting the faecal sludge treatment site over the average faecal coliforms of influent entering the faecal sludge treatment site in the same period.

References, tips, examples
If the number of faecal coliforms in the influent of the treatment plant is 1*10^6 and the number of faecal coliforms in the effluent is 1000:
log10(1*10^6)-log(1000) = 3 Log Reduction. Example values from Zambia: 2*107 CFU/100ml for pit latrines and 1*105 CFU/100ml for septic tanks

Why is it important to measure it
Faecal sludge characteristics varies widely between cities, types of on site sanitation systems and type of emptying system used. Even samples taken from the same pit latrine have been shown to have significant variation in standard physio-chemical testing. Such characteristics impact how sludge can be processed following removal. Stabilised sludge is very poor in terms of gas release in an anaerobic digester.

Definition of the indicator
Operation expenditure includes the daily average of:
– Staff costs
– Energy costs (especially high when electricity needs to be generated separately)
– Chemical costs
– Transport costs
– Administration costs
– Water for cleaning / operating costs
– Personal Protection Equipment costs
– Etc.
divided by real input flow.
This doesn’t include the desludging costs.

How to measure or calculate it
Review the operation and maintenance SOPs, the purchase documents and ask the staff. All the expenditure for operation has to be considered and divided by the real input flow (see indicator). Expenditure for daily, weekly and monthly operation, as well as yearly and extraordinary maintenance should be considered as a daily average. It includes the cost of human resources involved in the operation and maintenance of the plant, but it doesn’t include the costs related to desludging activities.

References, tips, examples
Typical O&M costs for faecal sludge treatment plants around the world are 6-10 USD/m3.

Why is it important to measure it
This indicator is useful to know the economical efficiency of a faecal sludge treatment system.