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Phase I Field Mobilization Report
February 20-21, 2026 | Submitted March 15, 2026

Bhadaure Settlement

WASH Baseline and Technical Reconnaissance

Bhadaure Eco-Sanitation Team

IOE Pulchowk Campus

Executive Summary

Objective: Synthesize socio-economic, technical, and institutional data to determine the feasibility of eco-sanitation interventions in the Bhadaure Settlement. Goal: Standardized, disaster-resilient infrastructure.

37.5% Deficit

Lack private sanitation facilities. 29.2% rely on shared toilets; 8.3% practice open defecation.

100% Soil Risk

Expansive, impermeable red clay across sloped terrain renders standard soak-pits structurally unfeasible.

Water Scarcity

50.0% travel >5 minutes for water, restricting conventional water-reliant pour-flush systems.

70.8% Equity

Community is highly motivated, ready to contribute physical labor and local materials ("sweat equity").

Methodology & Data Aggregation

A mixed-methods research design utilizing a Data Triangulation approach to simultaneously measure human behavior, physical constraints, and social dynamics.

WASH Baseline

n = 24

Households

Targeted individual family units (129 individuals) to establish demographics, income, and sanitation practices.

Technical Recon

n = 8

Plots Sampled

Evaluated physical constraints: topographical gradients, surface soil characteristics, and foundational requirements.

Neighboring Community

n = 4

Adjacent Households

Assessed the nearer community of Bhadaure to contextualize shared challenges and broader social dynamics.

Fieldwork executed in Feb 2026 using digital surveys with precise GPS mapping.
Demographics & Household Structure

Population Dynamics

The settlement exhibits moderate-to-high population density. Understanding the structure is key for sizing sanitation facilities appropriately.

  • Household Size: Average is 5.4 individuals (ranging from 2 to 11 members per roof).
  • Family Typology: The vast majority operate as Nuclear families, suggesting sanitation will be managed by individual units rather than large extended compounds.

Family Typology

Ethnic Composition & Stability

Ethnic Breakdown

Social Validation

The settlement is ethnically homogeneous, consisting entirely of historically marginalized communities (Sarki & Kami). This uniform marginalization validates the absolute necessity of external/CSR intervention where market-driven models have failed.

Residency Stability

An overwhelming 91.7% of households are native to the settlement. This exceptional stability guarantees that capital invested in infrastructure will serve a permanent, vested population unlikely to abandon the site.

Gender Representation & Leadership

The Decision Paradox

An analysis of the respondent data reveals a critical divergence between household leadership and domestic engagement regarding WASH issues.

The Data Advantage

Women overwhelmingly answered the survey (71%). Data regarding sanitation deficits, menstrual hygiene, and water burdens is deeply accurate and lived.

Financial Control

Conversely, 82.6% of households are male-headed. Final financial and structural approvals are male-led.

Conclusion: Mobilization must explicitly engage both genders to secure construction approvals while ensuring designs meet female hygiene needs.

Respondents vs Head of Household

Economic Baseline & Vulnerability

Income Brackets (Monthly NPR)

Financial Polarity

Extreme Vulnerability

45.9% survive on < 15,000 NPR monthly (with 16.7% earning under 5,000 NPR). Expecting this segment to self-fund high-quality toilets is financially impossible.

Remittance Dependency

Conversely, 29.2% earn > 30,000 NPR, likely driven by overseas remittance (compounding the out-migration of working-age males noted by surveyors).

Unstable Sources

The largest segments rely exclusively on unstable Daily Wage labor (23.8%) and subsistence farming.

Food Security & Land Ownership

Food Insecurity

Economic fragility is starkly reflected in food security metrics. Only 29.2% of households produce enough food to last year-round.

Alarmingly, 29.2% face severe food insecurity, producing only enough for 6 months or less.

Strategic Asset: Land Tenure

Despite extreme financial insecurity, 100% of surveyed households legally own their land. This eliminates legal risks of building on squatter land and guarantees that permanent capital investments (retaining walls, septic vaults) are fully protected.

Food Security Duration

The Sanitation Gap

37.5% of the settlement operates without private sanitation.

Current Facility Distribution

Shared Facilities (29.2%)

While an improvement over open fields, these quickly degrade due to a lack of defined ownership and coordinated cleaning schedules, leading to rapid pathogen spread.

Open Defecation (8.3%)

A persistent minority still practices OD in nearby forests, posing severe contamination risks to local groundwater and surface runoff during the monsoon.

Target Demographic: The 37.5% Deficit
Gendered Impacts of WASH Deficits

Sanitation deficits disproportionately impact women. 70.6% of female respondents confirmed acute challenges.

Specific Vulnerabilities Reported

Engineering Mandates

The new eco-toilets must explicitly address these data points:

  • Secure Hardware: Internal lockable doors to guarantee absolute privacy and safety.
  • Hygiene Logistics: Localized internal water storage (small tanks) inside the unit to manage menstrual hygiene.
  • Passive Lighting: Translucent roofing sheets to provide natural light for safety at dawn/dusk.
Water Accessibility & Logistics

Commute Time to Water Source

Critical failure point for pour-flush systems.

Primary Sources

  • 100% rely on Springs/Padhero for drinking water.
  • 58.3% utilize metered pipe taps for other uses.
  • Water is available year-round (no seasonal drying).

The Hauling Burden

A standard pour-flush toilet requires 3 to 5 liters of water per flush. For the 50% of households situated >5 minutes from a tap, forcing them to haul hundreds of liters of water uphill weekly merely to flush a toilet is socially unsustainable.

Field Documentation
Field Documentation
Field Documentation
Field Documentation
Community Prioritization

Systemic Challenge Rankings

Priority 1: Sanitation

42.0% explicitly ranked "Toilet / Sanitation" as their absolute #1 need, far surpassing Unemployment (10.5%). Secondary concerns featured Lack of Education (41.7% of Priority 2).

Actionable Insight

The community is not having this project forced upon them; they are actively requesting it. This high level of organic demand directly correlates with the exceptional willingness to contribute physical labor (70.8%).

Geotechnical Baseline: Surface Observations

Universal Baseline: 100% of surveyed plots present highly restrictive physical conditions based on surface observations.

Red Clayey Soil

The predominant soil type observed across all sampled plots is red clay. This presents two critical engineering challenges that must dictate design choices:

1. Impermeability (Percolation Failure)

Extremely low hydraulic conductivity. If standard soak pits are constructed here, the effluent will not drain into the soil. The pits will inevitably pool and overflow, causing severe biological hazards at the surface.

2. Expansive Nature (Shrink-Swell)

This soil type swells massively during the monsoon season and shrinks during the dry winter. This continuous movement induces immense lateral and upward pressure, cracking standard rigid masonry walls easily.

Topography & Disaster Risk Reduction

Sloped Terrain Vulnerability

The settlement is situated on gentle to steep slopes. Combined with the expansive clay, this topography creates severe landslide and erosion risks during the monsoon season.

Standard flat-plain designs will categorically fail in this environment without significant modification.

Mandated Structural Upgrades:

  • No Slab-On-Grade: Standard shallow slabs are vulnerable to washing out.
  • Aggressive Site Grading: Required to divert water away from the structure.
  • Cut-and-Fill Terracing: Mandatory to establish stable platforms for superstructures.
  • Plinth Protection: Concrete aprons around the base are necessary to manage surface runoff and prevent under-scouring.
Foundation Engineering

To counteract the highly sloped terrain and loose, expansive red clayey soil, standard excavations are at extremely high risk of collapse and differential settlement.

Continuous Strip Footings

Mandate: Isolated column footings are strictly prohibited. The substructure must utilize a continuous strip foundation (rubble stone masonry or reinforced concrete) excavated well below the active moisture zone to mitigate differential settlement.

Stone Masonry Lining

Mandate: For any underground pits (if a modified pour-flush is conditionally approved), a robust partial stone masonry lining must be provided. The surveyor field notes explicitly emphasize this to prevent pit wall collapse in the wet clay.

Stepped Foundations

Mandate: Due to sloped topography, foundations must be stepped, adapting to the natural contour of the hill. This minimizes the need for dangerously deep excavations on the uphill side while maintaining integrity.

Structural Anchorage & Wind Hazards

Wind & Uplift Vulnerability

Many homes and existing structures in Bhadaure were built using post-2015 earthquake relief funds, heavily utilizing lightweight materials like Corrugated Galvanized Iron (CGI) tin sheets.

The Threat

High-velocity evening winds flowing through the hilly terrain regularly threaten these lightweight roofs. Surveyor notes highlight that locals currently use heavy stones to press roofs down—a highly unsafe, temporary fix.

Anchorage Mandates

  • Ferrocement Priority: Where budget allows, prioritize heavy ferrocement slab roofs over tin sheets for sanitation units.
  • J-Bolts & Washers: If CGI sheets must be used, they must be secured using J-bolts with large washers at close spacing to purlins.
  • Continuous Ring Beam: Purlins must be tied down to a continuous wooden or RCC ring beam.
  • GI Straps: Utilize GI (Galvanized Iron) straps for robust wall-to-roof anchorage.
Field Documentation
Drainage Area Field Photo
Drainage & Topographical Mapping

Identifying high-risk water accumulation zones across the settlement.

Drainage and Topographical Map
Engineering Implication: Households situated near or downhill from these historically mapped zones absolutely cannot utilize standard soak pits, as effluent will pool to the surface immediately during the monsoon. Above-ground vaults are the only viable solution here.
Construction Logistics & Access

The Final Mile Hurdle

Infrastructure delivery is severely hampered not just by the macro-terrain, but by the micro-access paths to individual household plots.

Poor Road Conditions

Access roads to the settlement are hazardous, particularly for heavy transport or even two-wheelers, which restricts the delivery of large bulk construction materials directly to the site.

Manual Portering Requirement

Because trucks must drop materials far from the actual construction plots, intense manual portering ("sweat equity") will be required to haul cement, rebar, and aggregate up and down the steep paths to each household. This necessitates extreme community coordination.

Bio-Engineering Solutions: Vetiver Grass

Integrating physical construction with natural, ecological solutions to maximize budget and community impact.

The Stabilization Problem

Physical dry-stone retaining walls are highly effective but expensive and require moving massive amounts of heavy stone down narrow paths.

The Vetiver Solution

Integration of Vetiver Grass planting is highly recommended. Its massive, deep root systems (growing up to 3 meters deep) act as a low-cost, highly effective "living nail" to bind and stabilize the loose red clay slopes behind and around the new toilet units, preventing minor landslides without concrete.

Surface Grass
Deep Root "Nails" (up to 3m)
Irrigation Integration

With 29.2% facing severe food insecurity, addressing water inequality for agriculture is a crucial secondary engineering goal.

The Unused Potential

Currently, large tracts of land at the settlement's edge remain uncultivated due to lack of irrigation. Water scarcity limits farming solely to the monsoon period. The existing metered water systems are underutilized due to cost constraints for bulk watering.

The Systemic Solution

By re-purposing these metered sources and connecting them to highly efficient drip and micro-sprinkler irrigation systems, water usage is minimized while maximizing crop yield.

The Circular Economy: This irrigation strategy becomes exponentially more effective when combined with the safe, nutrient-rich agricultural compost generated by the new Eco-San (UDDT) toilets.
Design Suitability Matrix

Solving for: Water Scarcity + Impermeable Red Clay + Sloped Terrain

Highly Rec.

Eco-San (UDDT)

Urine-Diverting Dry Toilet. Separates waste at source into above-ground vaults.

Why it fits: ZERO flush water needed. Bypasses clay impermeability entirely. Safe from deep excavation risks. Yields usable compost.
Conditional

Septic + Wetland

Sealed septic tank flowing into a shallow constructed reed bed.

Why it fits: Surface level management. Clay acts as a natural liner. But requires high water volume and flat space.
Not Rec.

Pour-Flush ET Mound

Pumped effluent into a large engineered sand mound relying on transpiration.

Why it fails: Constructing level mounds on steep slopes severely risks landslides. Economically unfeasible to import sand.
The Eco-San Concept (UDDT) Breakown
UDDT Eco-San Toilet

Urine-Diverting Dry Toilet

  • Waterless: Requires absolutely zero flush water, solving the hauling burden for the 50% of households far from taps.
  • Source Separation: A specialized pan diverts urine (for evapotranspiration) and feces (into the vault).
  • Safe Vaults: Built above ground. This completely bypasses the dangers of excavating into impermeable, expansive red clay.
  • Composting: Feces are dehydrated using household ash, eventually yielding safe agricultural compost for farming.
UDDT Design
UDDT Design Field Photo
Institutional Capability & Social Dynamics

Governance Gap

50% report "Weak" Ward relations and 75% feel budget distribution is unfair. Project team must act as a formal mediator to ensure municipal buy-in without alienating locals.

Grassroots Management

100% consensus on active Women's Groups. Bypass top-down contracts; partner directly with these groups to coordinate daily volunteer rosters and material drops.

Gender-Centric Handover

Because men hold veto power but women face the burdens, final commissioning mandates physical sign-off by the female head of household.

Resource Mobilization

70.8%
"Sweat Equity" Asset

of the community is ready to provide physical labor and porter local materials.

Overall Risk Register
Category Identified Risk Impact Proposed Mitigation Strategy
Geotechnical Expansive red clay causes foundation cracking. High Mandate continuous strip footings with 150mm sand/gravel cushion and RCC plinth bands.
Geotechnical Standard soak pits overflow due to clay impermeability. High Strictly pivot to UDDT (waterless) or surface-level constructed wetlands.
Topographical Landslides/erosion during monsoon on sloped plots. High Construct dry-stone retaining walls; plant Vetiver grass; aggressive surface water grading.
Financial Extreme poverty prevents households from funding toilets. High Shift contribution model entirely to "sweat equity" (labor and local stone) rather than cash.
Institutional Weak relationship with Ward/Palika halts construction. Med Project team acts as formal mediator, keeping local govt informed while operating grassroots.
Social Facilities fail to meet women's specific hygiene needs. Med Mandate female household sign-off on final design; ensure internal locks & water storage.
Project Field Photo
Project Field Photo
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Phase II Transition Ready

Thank you for your attention.

Bhadaure Eco-Sanitation Team

Institute of Engineering, Pulchowk Campus | March 2026