| Title: | Economic Analysis of Soil and Water Conservation Measures in Watersheds |
| Version: | 0.1.0 |
| Description: | Provides functions and benchmark datasets for the economic appraisal of soil and water conservation (SWC) measures in watershed development projects. Implements benefit-cost ratio (BCR), net present value (NPV), internal rate of return (IRR) via the bisection method of Brent (1973, ISBN:9780130223715), modified BCR, marginal rate of return using the CIMMYT (1988, ISBN:9686127127) method, payback period, soil loss economic valuation via the Universal Soil Loss Equation of Wischmeier and Smith (1978, ISBN:0160016258), groundwater recharge valuation, employment generation ratio, sensitivity analysis, switching value analysis, and Monte Carlo simulation. Six datasets are included: state-wise BCR benchmarks from NABARD (2019) watershed evaluations, USLE erodibility parameters for Indian soil orders from NBSS and LUP, rainfall erosivity for twenty Indian districts from IMD data, SWC unit cost norms from PMKSY-WDC (GoI 2015), and two hypothetical datasets for illustration. Methods follow Gittinger (1982, ISBN:9780801825439) and Squire and van der Tak (1975, ISBN:9780801816697). |
| License: | GPL (≥ 3) |
| Encoding: | UTF-8 |
| Language: | en-US |
| LazyData: | true |
| RoxygenNote: | 7.3.3 |
| Depends: | R (≥ 4.1.0) |
| Imports: | stats, graphics, grDevices, utils |
| Suggests: | testthat (≥ 3.0.0), knitr, rmarkdown, covr |
| VignetteBuilder: | knitr |
| Config/testthat/edition: | 3 |
| NeedsCompilation: | no |
| Packaged: | 2026-04-13 05:18:42 UTC; acer |
| Author: | Sadikul Islam |
| Maintainer: | Sadikul Islam <sadikul.islamiasri@gmail.com> |
| Repository: | CRAN |
| Date/Publication: | 2026-04-16 20:10:02 UTC |
swcEcon: Economic Analysis of Soil and Water Conservation Measures
Description
Provides functions and benchmark datasets for the economic appraisal of soil and water conservation (SWC) measures in watershed development projects. Functions cover financial appraisal (BCR, NPV, IRR, PBP, MRR), soil loss valuation (USLE), water resource valuation, employment generation, sensitivity analysis, switching value, Monte Carlo simulation, a full pipeline runner, and automated HTML report generation.
Author(s)
Maintainer: Sadikul Islam sadikul.islamiasri@gmail.com (ORCID)
References
Brent, R.P. (1973). Algorithms for Minimization Without Derivatives. Prentice-Hall. ISBN: 9780130223715.
CIMMYT (1988). From Agronomic Data to Farmer Recommendations. CIMMYT, Mexico DF. ISBN: 9686127127.
Gittinger, J.P. (1982). Economic Analysis of Agricultural Projects, 2nd ed. Johns Hopkins University Press. ISBN: 9780801825439.
GoI (2015). Common Guidelines for Watershed Development Projects under PMKSY-WDC. Ministry of Rural Development, New Delhi.
Joshi, P.K., Jha, A.K., Wani, S.P., Joshi, L. and Shiyani, R.L. (2005). Meta-Analysis to Assess Impact of Watershed Program and People's Participation. IWMI Research Report 8. ISBN: 9290906677.
NABARD (2019). Operational Guidelines: Watershed Development Fund. National Bank for Agriculture and Rural Development, Mumbai.
Squire, L. and van der Tak, H.G. (1975). Economic Analysis of Projects. Johns Hopkins University Press. ISBN: 9780801816697.
Wischmeier, W.H. and Smith, D.D. (1978). Predicting Rainfall Erosion Losses. USDA Agriculture Handbook No. 537. ISBN: 0160016258.
Benefit-cost ratio for SWC watershed projects
Description
Computes the discounted Benefit-Cost Ratio (BCR) for a SWC project. BCR is the ratio of present value of benefits to present value of costs.
Usage
calc_bcr(
investment,
annual_benefit,
annual_omc = 0,
life = 20L,
discount_rate = 0.12,
residual_value = 0,
benefit_lag = 0L
)
Arguments
investment |
Numeric. Capital investment (INR lakh or consistent unit). |
annual_benefit |
Numeric. Annual gross benefit. Scalar or vector of
length |
annual_omc |
Numeric. Annual O&M cost. Default |
life |
Integer. Project design life (years). Default |
discount_rate |
Numeric. Annual discount rate as proportion
(e.g. |
residual_value |
Numeric. Salvage value at project end. Default |
benefit_lag |
Integer. Gestation years before benefits begin. Default |
Details
BCR = \frac{\sum_{t=1}^{n} B_t/(1+r)^t + S/(1+r)^n}{
I_0 + \sum_{t=1}^{n} C_t/(1+r)^t}
Decision rules (Gittinger 1982; GoI 2008): BCR > 1.0 is viable; BCR >= 1.5 meets NABARD threshold for watershed funding (NABARD 2019); BCR < 1.0 is not viable at the chosen discount rate.
Value
A named list of class "swcEcon_bcr" with elements:
bcr, pv_benefits, pv_costs, verdict,
and inputs.
References
Gittinger, J.P. (1982). Economic Analysis of Agricultural Projects, 2nd ed. Johns Hopkins University Press. ISBN: 9780801825439.
GoI (2008). Guidelines for Economic Analysis of Projects. Planning Commission of India, New Delhi.
NABARD (2019). Operational Guidelines: Watershed Development Fund. National Bank for Agriculture and Rural Development, Mumbai.
Examples
calc_bcr(investment = 20, annual_benefit = 6,
annual_omc = 0.8, life = 20, discount_rate = 0.12)
# With 2-year gestation period
calc_bcr(investment = 35, annual_benefit = 9, annual_omc = 1.2,
life = 20, discount_rate = 0.12, benefit_lag = 2)
Employment generation ratio for SWC projects
Description
Computes the Employment Generation Ratio (EGR) and checks compliance with the MGNREGS 60 per cent labour norm.
Usage
calc_employment(employment_days, investment_lakh, wages_per_day = 250)
Arguments
employment_days |
Numeric. Total person-days generated. |
investment_lakh |
Numeric. Total investment (INR lakh). |
wages_per_day |
Numeric. Daily wage rate (INR). Default |
Details
EGR = \frac{\text{Person-days}}{\text{Investment (INR lakh)}}
Value
A named list with egr_days_per_lakh, total_wage_bill_inr,
labour_share_pct, and mgnregs_60pct_norm.
References
GoI (2023). Mahatma Gandhi National Rural Employment Guarantee Scheme: Operational Guidelines, 4th ed. Ministry of Rural Development, New Delhi.
NABARD (2019). Operational Guidelines: Watershed Development Fund. National Bank for Agriculture and Rural Development, Mumbai.
Examples
calc_employment(employment_days = 45000, investment_lakh = 50,
wages_per_day = 250)
Internal rate of return for SWC watershed projects
Description
Computes the IRR – the discount rate at which NPV equals zero – using the bisection algorithm of Brent (1973).
Usage
calc_irr(
investment,
annual_benefit,
annual_omc = 0,
life = 20L,
lower = 0,
upper = 2
)
Arguments
investment |
Numeric. Capital investment. |
annual_benefit |
Numeric. Annual gross benefit. |
annual_omc |
Numeric. Annual O&M cost. Default |
life |
Integer. Project life (years). Default |
lower |
Numeric. Lower search bound. Default |
upper |
Numeric. Upper search bound. Default |
Details
Benchmarks: 12 per cent (Planning Commission, GoI 2008); 12–15 per cent (NABARD 2019); 10–15 per cent (World Bank 1998).
Value
A list of class "swcEcon_irr" with irr,
irr_pct, converged, and benchmark comparisons.
References
Brent, R.P. (1973). Algorithms for Minimization Without Derivatives. Prentice-Hall. ISBN: 9780130223715.
GoI (2008). Guidelines for Economic Analysis of Projects. Planning Commission of India, New Delhi.
NABARD (2019). Operational Guidelines: Watershed Development Fund. National Bank for Agriculture and Rural Development, Mumbai.
Examples
calc_irr(investment = 20, annual_benefit = 6,
annual_omc = 0.8, life = 20)
Additional crop income from SWC-enabled irrigation
Description
Additional crop income from SWC-enabled irrigation
Usage
calc_irrigation_benefit(
irrig_area_ha,
yield_increase_t_ha,
crop_price_inr_t,
input_cost_inr_ha = 8000
)
Arguments
irrig_area_ha |
Numeric. Additional irrigated area (ha). |
yield_increase_t_ha |
Numeric. Yield increase (t/ha). |
crop_price_inr_t |
Numeric. Farm-gate crop price (INR/t). |
input_cost_inr_ha |
Numeric. Additional input cost (INR/ha).
Default |
Value
A named list with gross, additional cost, and net benefit.
References
Joshi, P.K., Jha, A.K., Wani, S.P., Joshi, L. and Shiyani, R.L. (2005). Meta-Analysis to Assess Impact of Watershed Program and People's Participation. IWMI Research Report 8. ISBN: 9290906677.
Examples
calc_irrigation_benefit(irrig_area_ha = 80, yield_increase_t_ha = 1.6,
crop_price_inr_t = 18000, input_cost_inr_ha = 8000)
Modified benefit-cost ratio
Description
Computes the Modified BCR: MBCR = (TB - OC) / CC (Gittinger 1982).
Usage
calc_mbcr(total_benefit, operating_cost, capital_cost)
Arguments
total_benefit |
Numeric. Total benefit over project life. |
operating_cost |
Numeric. Total operating costs over life. |
capital_cost |
Numeric. Initial capital investment. |
Value
A list of class "swcEcon_mbcr" with mbcr and
interpretation.
References
Gittinger, J.P. (1982). Economic Analysis of Agricultural Projects, 2nd ed. Johns Hopkins University Press. ISBN: 9780801825439.
Examples
calc_mbcr(total_benefit = 80, operating_cost = 12, capital_cost = 20)
Marginal rate of return (CIMMYT method)
Description
Computes MRR following CIMMYT (1988): the return per unit of additional investment when switching from current practice to a SWC technology.
Usage
calc_mrr(nb_with, nb_without, cost_with, cost_without, min_mrr = 100)
Arguments
nb_with |
Numeric. Net benefit per ha with SWC technology. |
nb_without |
Numeric. Net benefit per ha without SWC. |
cost_with |
Numeric. Variable cost per ha with SWC. |
cost_without |
Numeric. Variable cost per ha without SWC. |
min_mrr |
Numeric. Minimum acceptable MRR (per cent). Default |
Details
MRR = \frac{NB_{with} - NB_{without}}{C_{with} - C_{without}}
\times 100
A minimum acceptable MRR of 100 per cent is recommended by CIMMYT (1988).
Value
A list of class "swcEcon_mrr" with mrr,
marginal_benefit, marginal_cost, and recommendation.
References
CIMMYT (1988). From Agronomic Data to Farmer Recommendations. CIMMYT, Mexico DF. ISBN: 9686127127.
Byerlee, D. and Collinson, M. (1980). Planning Technologies Appropriate to Farmers. CIMMYT, Mexico DF.
Examples
calc_mrr(nb_with = 18000, nb_without = 11000,
cost_with = 16000, cost_without = 11500)
Net present value for SWC watershed projects
Description
Computes the Net Present Value (NPV) by discounting annual net benefits.
Usage
calc_npv(
investment,
annual_benefit,
annual_omc = 0,
life = 20L,
discount_rate = 0.12,
residual_value = 0
)
Arguments
investment |
Numeric. Capital investment. |
annual_benefit |
Numeric. Annual gross benefit. |
annual_omc |
Numeric. Annual O&M cost. Default |
life |
Integer. Project life (years). Default |
discount_rate |
Numeric. Discount rate. Default |
residual_value |
Numeric. Salvage value. Default |
Details
NPV = \sum_{t=1}^{n}\frac{B_t - C_t}{(1+r)^t}
+ \frac{S}{(1+r)^n} - I_0
Value
A list of class "swcEcon_npv" with npv,
cashflows (data frame), and decision.
References
Gittinger, J.P. (1982). Economic Analysis of Agricultural Projects, 2nd ed. Johns Hopkins University Press. ISBN: 9780801825439.
Squire, L. and van der Tak, H.G. (1975). Economic Analysis of Projects. Johns Hopkins University Press. ISBN: 9780801816697.
Examples
r <- calc_npv(investment = 20, annual_benefit = 6,
annual_omc = 0.8, life = 20, discount_rate = 0.12)
print(r)
head(r$cashflows)
Nutrient replacement cost from soil erosion
Description
Estimates the annual economic cost of NPK nutrients lost through soil erosion based on soil nutrient content and fertiliser prices.
Usage
calc_nutrient_cost(
soil_loss_t_ha,
area_ha,
n_kg_per_t = 0.5,
p_kg_per_t = 0.08,
k_kg_per_t = 1.2,
n_price = 20,
p_price = 50,
k_price = 25
)
Arguments
soil_loss_t_ha |
Numeric. Annual soil loss (t/ha/yr). |
area_ha |
Numeric. Catchment area (ha). |
n_kg_per_t |
Numeric. N per tonne of soil (kg/t). Default |
p_kg_per_t |
Numeric. P per tonne (kg/t). Default |
k_kg_per_t |
Numeric. K per tonne (kg/t). Default |
n_price |
Numeric. N fertiliser price (INR/kg). Default |
p_price |
Numeric. P fertiliser price (INR/kg). Default |
k_price |
Numeric. K fertiliser price (INR/kg). Default |
Value
A named list with nutrient quantities lost and replacement costs.
References
Katyal, J.C. and Sharma, B.D. (1991). Nutrients in soil fertility. Fertiliser News, 36(4), 13–24.
Examples
data(usle_india_soils)
s <- usle_india_soils[usle_india_soils$soil_series == "Alfisols", ]
calc_nutrient_cost(soil_loss_t_ha = 12, area_ha = 200,
n_kg_per_t = s$n_kg_per_t,
p_kg_per_t = s$p_kg_per_t,
k_kg_per_t = s$k_kg_per_t)
Payback period for SWC projects
Description
Computes simple and discounted payback periods and assesses adoption likelihood. PBP is the strongest predictor of voluntary SWC uptake among smallholders in rainfed India (Joshi et al. 2005).
Usage
calc_pbp(
investment,
annual_benefit,
annual_omc = 0,
life = 20L,
discount_rate = 0.12
)
Arguments
investment |
Numeric. Capital investment. |
annual_benefit |
Numeric. Annual gross benefit. |
annual_omc |
Numeric. Annual O&M cost. Default |
life |
Integer. Project life (years). Default |
discount_rate |
Numeric. Discount rate. Default |
Value
A list of class "swcEcon_pbp" with simple_pbp,
discounted_pbp, and adoption.
References
Joshi, P.K., Jha, A.K., Wani, S.P., Joshi, L. and Shiyani, R.L. (2005). Meta-Analysis to Assess Impact of Watershed Program and People's Participation. IWMI Research Report 8. ISBN: 9290906677.
Singh, A.J., Lal, P. and Sharma, S.K. (2006). Economics of adoption of improved technologies in rainfed farming systems. Indian Journal of Agricultural Economics, 61(3), 420–435.
Examples
calc_pbp(investment = 20, annual_benefit = 6, annual_omc = 0.8)
Economic cost of soil loss using the USLE
Description
Estimates annual economic cost of soil loss using the Universal Soil Loss Equation (Wischmeier and Smith 1978) and converts the reduction achieved by a SWC measure to monetary value.
Usage
calc_soil_loss_cost(
R,
K,
LS,
C_pre,
C_post,
P_pre = 1,
P_post = 0.5,
area_ha = 1,
nutrient_cost_per_t = 1000,
years = 1
)
Arguments
R |
Numeric. Rainfall erosivity factor (MJ mm / ha hr yr). Use
|
K |
Numeric. Soil erodibility factor. Use
|
LS |
Numeric. Slope length-gradient factor (dimensionless). |
C_pre |
Numeric. Cover-management factor before SWC. |
C_post |
Numeric. Cover-management factor after SWC. |
P_pre |
Numeric. Support practice factor before SWC. Default |
P_post |
Numeric. Support practice factor after SWC. Default |
area_ha |
Numeric. Treatment area (ha). Default |
nutrient_cost_per_t |
Numeric. Nutrient replacement cost per tonne
of soil (INR/t). Default |
years |
Numeric. Annualisation multiplier. Default |
Details
A = R \cdot K \cdot LS \cdot C \cdot P \quad (t/ha/yr)
The annual economic benefit = (A_pre - A_post) x area x nutrient cost.
Value
A list of class "swcEcon_soil" with soil_loss_pre,
soil_loss_post, soil_saved_ha, soil_saved_total,
annual_benefit_inr, and pct_reduction.
References
Wischmeier, W.H. and Smith, D.D. (1978). Predicting Rainfall Erosion Losses. USDA Agriculture Handbook No. 537. ISBN: 0160016258.
Singh, G., Babu, R., Narain, P., Bhushan, L.S. and Abrol, I.P. (1992). Soil erosion rates in India. Journal of Soil and Water Conservation, 47(1), 97–99.
Katyal, J.C. and Sharma, B.D. (1991). Nutrients in soil fertility. Fertiliser News, 36(4), 13–24.
Examples
data(usle_india_soils)
K <- usle_india_soils[usle_india_soils$soil_series == "Vertisols", "k_mean"]
calc_soil_loss_cost(R = 720, K = K, LS = 4.2,
C_pre = 0.35, C_post = 0.18,
P_pre = 1.0, P_post = 0.5, area_ha = 500)
Switching value analysis for SWC projects
Description
Computes how much costs can rise (or benefits fall) before BCR = 1.0. A higher switching value indicates greater robustness to estimation error (Gittinger 1982; World Bank 1998).
Usage
calc_switching_value(
investment,
annual_benefit,
annual_omc = 0,
life = 20L,
discount_rate = 0.12
)
Arguments
investment |
Numeric. Capital investment. |
annual_benefit |
Numeric. Annual gross benefit. |
annual_omc |
Numeric. Annual O&M cost. Default |
life |
Integer. Project life (years). Default |
discount_rate |
Numeric. Discount rate. Default |
Value
A list of class "swcEcon_sv" with switching values and
interpretations.
References
Gittinger, J.P. (1982). Economic Analysis of Agricultural Projects, 2nd ed. Johns Hopkins University Press. ISBN: 9780801825439.
World Bank (1998). Handbook on Economic Analysis of Investment Operations. World Bank, Washington DC.
Examples
calc_switching_value(investment = 20, annual_benefit = 6,
annual_omc = 0.8, life = 20,
discount_rate = 0.12)
Groundwater recharge and runoff harvesting value
Description
Estimates annual economic value of water benefits from a SWC watershed intervention.
Usage
calc_water_value(
area_ha,
rainfall_mm,
rc_pre = 0.35,
rc_post = 0.2,
harvest_pct = 45,
gw_recharge_pct = 20,
water_value_m3 = 3.5
)
Arguments
area_ha |
Numeric. Watershed area (ha). |
rainfall_mm |
Numeric. Mean annual rainfall (mm). |
rc_pre |
Numeric. Runoff coefficient before SWC (0–1). Default |
rc_post |
Numeric. Runoff coefficient after SWC (0–1). Default |
harvest_pct |
Numeric. Percentage of reduced runoff harvested. Default |
gw_recharge_pct |
Numeric. Percentage percolating to groundwater. Default |
water_value_m3 |
Numeric. Value of water (INR/m3). Default |
Details
Runoff volume (m3/yr) = RC x P x A x 10. Annual water benefit = (Q_harvest + Q_recharge) x water_value.
Value
A list of class "swcEcon_water" with runoff volumes and
annual_benefit_inr.
References
Joshi, P.K., Jha, A.K., Wani, S.P., Joshi, L. and Shiyani, R.L. (2005). Meta-Analysis to Assess Impact of Watershed Program and People's Participation. IWMI Research Report 8. ISBN: 9290906677.
Examples
data(rainfall_erosivity_india)
rf <- rainfall_erosivity_india[
rainfall_erosivity_india$district == "Pune", "annual_rf_mm"]
calc_water_value(area_ha = 500, rainfall_mm = rf,
rc_pre = 0.35, rc_post = 0.20)
Simulated farm-level SWC adoption survey dataset
Description
A hypothetically generated survey of 120 farm households from four Indian states. SWC adoption modelled via logistic regression. Not real survey data.
Usage
data(farmer_adoption)
Format
A data frame with 120 rows and 10 variables:
- farmer_id
Character. Farmer identifier.
- state
Character. State (Maharashtra, Rajasthan, Karnataka, MP).
- farm_size_ha
Numeric. Farm area (ha).
- education_yrs
Integer. Years of formal education.
- annual_income_lakh
Numeric. Annual household income (INR lakh).
- credit_access
Character. Institutional credit access (Yes/No).
- extension_visits
Integer. Extension agent visits per year.
- yield_pre_kharif
Numeric. Kharif yield before SWC (t/ha).
- adopted_swc
Integer. Adoption: 1 = adopted, 0 = not adopted.
- yield_post_kharif
Numeric. Kharif yield after SWC (t/ha);
NAfor non-adopters.
Details
Data status: HYPOTHETICALLY GENERATED. Not real survey data.
Adoption logit model:
logit(p) = -1.2 + 0.15 \cdot size + 0.08 \cdot edu +
0.20 \cdot income + 0.60 \cdot credit + 0.18 \cdot extension
Simulated adoption rate approx. 63 per cent. set.seed(2025).
Source
Hypothetical. See data-raw/generate_all_datasets.R.
References
Joshi, P.K., Jha, A.K., Wani, S.P., Joshi, L. and Shiyani, R.L. (2005). Meta-Analysis to Assess Impact of Watershed Program and People's Participation. IWMI Research Report 8. ISBN: 9290906677.
Singh, A.J., Lal, P. and Sharma, S.K. (2006). Economics of adoption of improved technologies in rainfed farming systems. Indian Journal of Agricultural Economics, 61(3), 420–435.
Examples
data(farmer_adoption)
mean(farmer_adoption$adopted_swc)
aggregate(adopted_swc ~ state, data = farmer_adoption, FUN = mean)
Generate an automated HTML economic appraisal report
Description
Produces a self-contained HTML report from a
run_swc_pipeline result, formatted for NABARD and
PMKSY-WDC project proposals.
Usage
generate_swc_report(
pipeline,
output_file = "swcEcon_report.html",
title = "SWC Economic Appraisal Report",
author = "swcEcon",
organisation = ""
)
Arguments
pipeline |
An object of class |
output_file |
Character. Output HTML path.
Default |
title |
Character. Report title. |
author |
Character. Author name. |
organisation |
Character. Organisation name. Default |
Value
Invisibly returns the path to the HTML file.
References
GoI (2015). Common Guidelines for Watershed Development Projects under PMKSY-WDC. Ministry of Rural Development, New Delhi.
NABARD (2019). Operational Guidelines: Watershed Development Fund. National Bank for Agriculture and Rural Development, Mumbai.
Examples
pl <- run_swc_pipeline(investment = 20, annual_benefit = 6,
annual_omc = 0.8, include_sensitivity = FALSE)
tmp <- tempfile(fileext = ".html")
generate_swc_report(pl, output_file = tmp, author = "Researcher")
Monte Carlo simulation for SWC project risk analysis
Description
Stochastic simulation of BCR and NPV distributions. Investment, benefit, and O&M costs are sampled from truncated Normal distributions; project life from a discrete Uniform; discount rate from a continuous Uniform. Follows Pouliquen (1970) as recommended by World Bank (1998).
Usage
monte_carlo_swc(
inv_mean = 20,
inv_cv = 0.1,
ben_mean = 6,
ben_cv = 0.15,
omc_mean = 0,
omc_cv = 0.2,
life_min = 15L,
life_max = 25L,
r_min = 0.1,
r_max = 0.14,
n_sim = 5000L,
seed = 42L
)
Arguments
inv_mean |
Numeric. Mean capital investment. Default |
inv_cv |
Numeric. CV for investment. Default |
ben_mean |
Numeric. Mean annual benefit. Default |
ben_cv |
Numeric. CV for benefit. Default |
omc_mean |
Numeric. Mean annual O&M. Default |
omc_cv |
Numeric. CV for O&M. Default |
life_min |
Integer. Minimum project life. Default |
life_max |
Integer. Maximum project life. Default |
r_min |
Numeric. Minimum discount rate. Default |
r_max |
Numeric. Maximum discount rate. Default |
n_sim |
Integer. Number of simulations. Default |
seed |
Integer or |
Value
A list of class "swcEcon_mc" with simulated BCR and NPV
vectors, probability estimates, and summary statistics.
References
ADB (2017). Guidelines for the Economic Analysis of Projects. Asian Development Bank, Manila. https://www.adb.org/documents/guidelines-economic-analysis-projects
Pouliquen, L.Y. (1970). Risk Analysis in Project Appraisal. World Bank Occasional Papers No. 11. Johns Hopkins University Press.
World Bank (1998). Handbook on Economic Analysis of Investment Operations. World Bank, Washington DC.
Examples
mc <- monte_carlo_swc(inv_mean = 20, ben_mean = 6, omc_mean = 0.8,
n_sim = 1000, seed = 42)
print(mc)
Print a swcEcon_result object
Description
Print a swcEcon_result object
Usage
## S3 method for class 'swcEcon_result'
print(x, ...)
Arguments
x |
An object of class |
... |
Ignored. |
Value
Invisibly returns x.
Rainfall erosivity (R-factor) for 20 Indian watershed districts
Description
USLE R-factor and climatological parameters for 20 representative watershed districts across major Indian agro-ecological zones.
Usage
data(rainfall_erosivity_india)
Format
A data frame with 20 rows and 8 variables:
- district
Character. District headquarters name.
- state
Character. State name.
- lat
Numeric. Latitude, decimal degrees (WGS84).
- lon
Numeric. Longitude, decimal degrees (WGS84).
- annual_rf_mm
Numeric. Mean annual rainfall (mm), 1981–2010.
- r_factor
Numeric. USLE R-factor (MJ mm / ha hr yr).
- kharif_pct
Numeric. June–September rainfall (per cent).
- mean_temp_c
Numeric. Mean annual temperature (degrees C).
Details
Data status: Real – derived from public domain data using published peer-reviewed formulae.
R-factor computed using Modified Fournier Index (MFI) and the regression: R = 38.46 + 3.48 x MFI (Bhattacharyya et al. 2010). Rainfall normals from IMD 0.25-degree gridded dataset, 1981–2010.
Source
IMD 0.25-degree gridded rainfall, 1981–2010. India Meteorological Department, Pune (public domain). https://imdpune.gov.in
References
Bhattacharyya, T., Pal, D.K., Mandal, C. and others (2010). Soils of India: Historical perspective, classification and recent advances. Current Science, 98(9), 1248–1257.
Pai, D.S. and others (2014). Development of a new high spatial resolution long period daily gridded rainfall data set over India. Mausam, 65(1), 1–18.
Examples
data(rainfall_erosivity_india)
rainfall_erosivity_india[rainfall_erosivity_india$r_factor > 900,
c("district", "state", "r_factor")]
Run the complete swcEcon economic appraisal pipeline
Description
Runs BCR, NPV, IRR, payback period, switching value, and optionally sensitivity analysis and Monte Carlo simulation in a single call.
Usage
run_swc_pipeline(
investment,
annual_benefit,
annual_omc = 0,
life = 20L,
discount_rate = 0.12,
project_name = "SWC Project",
include_sensitivity = TRUE,
include_monte_carlo = FALSE,
n_sim = 2000L,
...
)
Arguments
investment |
Numeric. Capital investment. |
annual_benefit |
Numeric. Annual gross benefit. |
annual_omc |
Numeric. Annual O&M cost. Default |
life |
Integer. Project life (years). Default |
discount_rate |
Numeric. Discount rate. Default |
project_name |
Character. Project label. Default |
include_sensitivity |
Logical. Run sensitivity analysis. Default |
include_monte_carlo |
Logical. Run Monte Carlo. Default |
n_sim |
Integer. Monte Carlo iterations. Default |
... |
Reserved for future use. |
Value
A list of class "swcEcon_pipeline" with steps
(sub-module results), summary (data frame), and metadata.
Examples
pl <- run_swc_pipeline(
investment = 20,
annual_benefit = 6,
annual_omc = 0.8,
project_name = "Hypothetical Check Dam Project",
include_sensitivity = FALSE,
include_monte_carlo = FALSE
)
print(pl)
Sensitivity analysis for SWC project appraisal
Description
Performs one-at-a-time (OAT) sensitivity analysis varying costs, benefits, and discount rate by specified ranges. Returns an 8-scenario table suitable for a tornado diagram.
Usage
sensitivity_analysis(
investment,
annual_benefit,
annual_omc = 0,
life = 20L,
discount_rate = 0.12,
cost_range_pct = 20,
benefit_range_pct = 20,
rate_range_pct = 3
)
Arguments
investment |
Numeric. Base capital investment. |
annual_benefit |
Numeric. Base annual benefit. |
annual_omc |
Numeric. Base annual O&M cost. Default |
life |
Integer. Project life (years). Default |
discount_rate |
Numeric. Base discount rate. Default |
cost_range_pct |
Numeric. Variation applied to costs (per cent).
Default |
benefit_range_pct |
Numeric. Variation applied to benefit (per cent).
Default |
rate_range_pct |
Numeric. Percentage points added/subtracted from
discount rate. Default |
Details
Required by NABARD (2019) for watershed project appraisal and recommended by World Bank (1998) for agricultural investment projects.
Value
A list of class "swcEcon_sens" with scenarios
(data frame), base_bcr, base_npv, and summary.
References
NABARD (2019). Operational Guidelines: Watershed Development Fund. National Bank for Agriculture and Rural Development, Mumbai.
World Bank (1998). Handbook on Economic Analysis of Investment Operations. World Bank, Washington DC.
Examples
sensitivity_analysis(investment = 20, annual_benefit = 6,
annual_omc = 0.8, life = 20,
discount_rate = 0.12)
State-wise SWC watershed economic benchmarks for India
Description
Typical ranges of BCR, IRR, unit cost, employment generation ratio, and payback period for watershed SWC projects across ten major Indian states. Compiled from published government evaluation reports.
Usage
data(swc_benchmarks)
Format
A data frame with 10 rows and 10 variables:
- state
Character. State name.
- agro_zone
Character. Agro-ecological zone.
- annual_rainfall_mm
Numeric. Mean annual rainfall (mm).
- bcr_min
Numeric. Minimum BCR from evaluated projects.
- bcr_max
Numeric. Maximum BCR.
- bcr_typical
Numeric. Median BCR across evaluations.
- irr_pct
Numeric. Typical IRR (per cent).
- cost_per_ha
Numeric. Investment cost per ha (INR).
- egr_person_days_per_lakh
Numeric. Person-days per INR lakh.
- pbp_years
Numeric. Typical payback period (years).
Details
Data status: Real – public domain government documents.
Compiled from NABARD WDF Annual Reports 2010–2022 (National Bank for Agriculture and Rural Development), PMKSY-WDC Progress Reports (https://dolr.gov.in), and CRIDA Technical Bulletins (ICAR). All BCR values computed at 12 per cent discount rate.
Source
NABARD WDF Annual Reports 2010–2022 (public domain). PMKSY-WDC Progress Reports, GoI (public domain).
References
NABARD (2019). Operational Guidelines: Watershed Development Fund. National Bank for Agriculture and Rural Development, Mumbai.
GoI (2015). Common Guidelines for Watershed Development Projects under PMKSY-WDC. Ministry of Rural Development, New Delhi.
Examples
data(swc_benchmarks)
swc_benchmarks[swc_benchmarks$bcr_typical >= 2.0,
c("state", "bcr_typical", "irr_pct")]
SWC measure unit cost norms (PMKSY-WDC 2015, updated to 2024)
Description
Standard unit costs for 18 common SWC structures from PMKSY-WDC Common Guidelines (GoI 2015), updated to 2024 using RBI CPI.
Usage
data(swc_cost_norms)
Format
A data frame with 18 rows and 7 variables:
- measure
Character. SWC measure name.
- unit
Character. Cost basis: per unit or per ha.
- norm_2015_inr
Numeric. PMKSY-WDC 2015 unit cost (INR).
- norm_2024_inr
Numeric. Estimated 2024 unit cost (INR).
- design_life_yr
Numeric. Expected design life (years).
- omc_pct_capital
Numeric. Annual O&M as per cent of capital.
- labour_pct
Numeric. Labour as per cent of total cost.
Details
Data status: Real – public domain Government of India guidelines.
Unit costs from PMKSY-WDC Common Guidelines (GoI 2015), available at https://dolr.gov.in. The 2024 estimates apply a CPI inflation factor of 1.65 (RBI CPI April 2015 to April 2024).
Source
GoI (2015). Common Guidelines for Watershed Development Projects under PMKSY-WDC. Ministry of Rural Development, New Delhi. Available at https://dolr.gov.in.
References
GoI (2015). Common Guidelines for Watershed Development Projects under PMKSY-WDC. Ministry of Rural Development, New Delhi.
CSWCRTI (2019). Technical Manual on Soil and Water Conservation Structures. ICAR, Dehradun (public domain).
Examples
data(swc_cost_norms)
swc_cost_norms[swc_cost_norms$design_life_yr >= 20,
c("measure", "norm_2024_inr", "design_life_yr")]
USLE erodibility and nutrient parameters for Indian soil orders
Description
Soil erodibility K-factor ranges and NPK nutrient content for eight major soil orders in Indian watersheds.
Usage
data(usle_india_soils)
Format
A data frame with 8 rows and 11 variables:
- soil_series
Character. Soil order (USDA classification).
- soil_order
Character. Common Indian name.
- states_typical
Character. States where order predominates.
- k_min
Numeric. Minimum K-factor (t ha hr / ha MJ mm).
- k_max
Numeric. Maximum K-factor.
- k_mean
Numeric. Mean K-factor for use when site data unavailable.
- oc_pct
Numeric. Typical organic carbon (per cent).
- t_value
Numeric. Permissible soil loss (t/ha/yr).
- n_kg_per_t
Numeric. N per tonne of soil (kg/t).
- p_kg_per_t
Numeric. P per tonne (kg/t).
- k_kg_per_t
Numeric. K per tonne (kg/t).
Details
Data status: Real – public domain scientific literature.
K-factor values from NBSS and LUP Technical Bulletin No. 132 (ICAR) and Singh et al. (1992). Nutrient content from Katyal and Sharma (1991).
Source
NBSS and LUP (2002). Soil Erodibility (K Factor) of Different Soils of India. Technical Bulletin 132. ICAR, Nagpur.
References
Wischmeier, W.H. and Smith, D.D. (1978). Predicting Rainfall Erosion Losses. USDA Agriculture Handbook No. 537. ISBN: 0160016258.
Singh, G., Babu, R., Narain, P., Bhushan, L.S. and Abrol, I.P. (1992). Soil erosion rates in India. Journal of Soil and Water Conservation, 47(1), 97–99.
Katyal, J.C. and Sharma, B.D. (1991). Nutrients in soil fertility. Fertiliser News, 36(4), 13–24.
Examples
data(usle_india_soils)
usle_india_soils[usle_india_soils$soil_series == "Vertisols", ]
Simulated watershed SWC project evaluation dataset
Description
A hypothetically generated dataset of 50 simulated SWC project evaluations for package illustration. Not real project data.
Usage
data(watershed_projects)
Format
A data frame with 50 rows and 18 variables:
- project_id
Character. Identifier (WS001–WS050).
- state
Character. Simulated state name.
- swc_measure
Character. Primary SWC measure.
- area_ha
Numeric. Watershed area (ha).
- investment_lakh
Numeric. Capital investment (INR lakh).
- annual_benefit_lakh
Numeric. Annual gross benefit (INR lakh).
- annual_omc_lakh
Numeric. Annual O&M cost (INR lakh).
- discount_rate_pct
Numeric. Discount rate (per cent).
- project_life
Numeric. Design life (years).
- soil_loss_pre
Numeric. Pre-SWC soil loss (t/ha/yr).
- soil_loss_post
Numeric. Post-SWC soil loss (t/ha/yr).
- gw_level_change_m
Numeric. Groundwater level change (m).
- irrig_area_added_ha
Numeric. Additional irrigated area (ha).
- employment_days
Numeric. Employment generated (person-days).
- hh_benefited
Numeric. Beneficiary households.
- bcr
Numeric. Computed benefit-cost ratio.
- npv_lakh
Numeric. Net present value (INR lakh).
- pbp_years
Numeric. Simple payback period (years).
Details
Data status: HYPOTHETICALLY GENERATED. Not real project data.
Generated with set.seed(2025). Parameter distributions
calibrated to NABARD WDF project characteristics (Joshi et al. 2005).
See data-raw/generate_all_datasets.R.
Source
Hypothetical. See data-raw/generate_all_datasets.R.
References
Joshi, P.K., Jha, A.K., Wani, S.P., Joshi, L. and Shiyani, R.L. (2005). Meta-Analysis to Assess Impact of Watershed Program and People's Participation. IWMI Research Report 8. ISBN: 9290906677.
Examples
data(watershed_projects)
summary(watershed_projects$bcr)
aggregate(bcr ~ swc_measure, data = watershed_projects, FUN = mean)