Through implementation research, Tetra Tech works with U.S. Agency for International Development’s (USAID) implementing partners globally to broaden the evidence base on the use and effectiveness of sanitation interventions.

Overall WASHpaLS continues to exceed expectations in most areas and has been an enormous benefit to the WASH sector and USAID's contributions and reputation in the sector.

Joseph T. Hamilton, Contracting Officer

Worldwide, 663 million people do not have access to safe drinking water, and 2.4 billion people lack access to improved sanitation. Inadequate access to water, sanitation, and hygiene (WASH) services is a major contributor to diarrheal illness, causing more than 840,000 deaths annually. It is a leading cause of infant and child morbidity and mortality and is increasingly thought to be a key determinant of childhood undernutrition and impaired growth. Tetra Tech is supporting the USAID Global Health Bureau’s Water, Sanitation and Hygiene Partnerships and Learning for Sustainability (WASHPaLS) project, which aims to reduce morbidity and mortality in children under five by ensuring programming employs high-impact, evidence-based environmental health and water supply, sanitation, and hygiene interventions.

WASHPaLS seeks to improve programming approaches for delivering high-impact WASH interventions by working with USAID, national and local governments, key sector donors and implementers to broaden the understanding of the impact of sanitation interventions, including community-led total sanitation (CLTS), market-based sanitation (MBS), hygienic environments (i.e., safe play spaces) for infants and young children, and menstrual hygiene management (MHM) in the workplace. By generating evidence around sanitation and hygiene programming paradigms, the program aims to achieve sustainability, scale, and improved health impact. Additionally, the project investigates innovative ideas in WASH behavior change programming such as habit science and gendered social norms through the management of a $1.5 million small grants program.

WASHPaLS has executed a learning agenda that includes operational research in eighteen countries to address key evidence gaps related to CLTS, MBS, hygienic environments for young children, and use of country-specific engagement plans to embed implementation research within local networks. WASHPaLS supports and collaborates with partner organizations including Clean, Fed & Nurtured Coalition, Sanitation Learning Hub, Global Handwashing Partnership, PRO-WASH, PSI, Sanitation and Water for All, United Nations Children’s Emergency Fund, WaterAid, and World Bank.

Research results were disseminated through peer-reviewed publications (3), presentations (70), webinars (6), and other communications materials (113). To date, WASHPaLS has produced 15 technical reports, including impact evaluations of USAID’s Cambodia Integrated Nutrition, Hygiene and Sanitation (NOURISH) and Kenya Resilient Arid Lands Partnership for Integrated Development (RAPID) projects, and performance evaluations of USAID’s Kenya Integrated Water Sanitation and Hygiene (KIWASH), Ghana WASH for Health (W4H), and RAPID activities, and hosted several webinars to disseminate the findings, all available on

WASHPaLS has executed nine small grants to investigate and generate evidence to support innovative ideas in WASH behavior change programming, including reducing exposure for infants and young children to animal feces. The grants are being implemented in Ethiopia, Nepal, Bangladesh, India, Philippines, and Uganda.