According to WiseGuy Reports, the Gravity Sewer Market was valued at USD 4.69 billion in 2024 and reached USD 4.89 billion in 2025. The market is projected to reach USD 7.5 billion by 2035, expanding at a CAGR of 4.3% during the 2026–2035 forecast period. Growing urbanization, increasing wastewater management requirements, aging sewer infrastructure, regulatory compliance pressures, and rising environmental concerns are supporting market growth. Prominent companies profiled include Golder Associates, Mott MacDonald, KBR, Arcadis, Jacobs, Black & Veatch, CDM Smith, Tetra Tech, WSP Global, and Stantec.
Market Overview
Gravity sewer systems remain an important component of wastewater infrastructure because they transport sewage primarily through natural gravitational flow. Their use across residential communities, commercial developments, industrial facilities, and municipal networks makes them a fundamental part of urban sanitation systems.
The market covers multiple material categories, including polyvinyl chloride, concrete, fiberglass, and steel. Material selection depends on factors such as installation conditions, expected service life, environmental exposure, structural requirements, and project economics.
Demand is being reinforced by population growth and urban expansion. As cities become more densely developed, governments and infrastructure operators need to expand wastewater collection networks while also addressing existing systems that require replacement, rehabilitation, or repair.
Market Size Reached in 2025
The Gravity Sewer Market reached USD 4.89 billion in 2025, compared with USD 4.69 billion in 2024. This increase reflects continued investment in wastewater collection infrastructure and the need to maintain reliable sanitation services.
Municipal projects represent a substantial source of demand, particularly in areas where population growth is putting pressure on existing wastewater networks. Residential and commercial construction can also generate requirements for new sewer connections and collection systems.
Replacement and repair activities are becoming increasingly significant as sewer networks installed decades ago approach the end of their functional lives. Infrastructure owners are therefore evaluating rehabilitation programs alongside conventional new installations.
Expected Market Size by 2035
The market is expected to reach USD 7.5 billion by 2035. Long-term expansion is likely to be supported by infrastructure modernization, government spending, urban development, and the need for improved wastewater management.
Aging networks represent a particularly important opportunity. Deteriorated pipes and outdated systems can increase maintenance requirements and operational risks, encouraging municipalities to invest in replacement and rehabilitation projects.
Emerging urban centers also provide opportunities for new gravity sewer installations. Infrastructure development accompanying residential, commercial, and industrial expansion can create sustained demand for sewer systems and associated engineering services.
Market CAGR
The market is forecast to register a CAGR of 4.3% between 2026 and 2035. This moderate growth trajectory reflects the essential nature of wastewater infrastructure and the long-term investment cycles associated with sewer projects.
Growth is influenced by public infrastructure budgets, regulatory standards, construction activity, and population expansion. Unlike discretionary infrastructure segments, wastewater collection systems are closely connected with public health and environmental management requirements.
Key Growth Drivers
Urbanization is one of the principal growth factors. Growing populations require expanded sanitation infrastructure, particularly in cities experiencing residential and commercial development.
Increasing wastewater management requirements are also supporting demand. Governments are placing greater emphasis on the safe collection and treatment of wastewater to protect water resources and meet environmental standards.
Infrastructure modernization creates another major driver. Aging sewer networks require replacement, repair, and rehabilitation, generating opportunities for material suppliers, engineering firms, contractors, and infrastructure service providers.
Environmental regulations further encourage investment. Compliance with wastewater and water-quality requirements can require municipalities and industrial operators to upgrade collection infrastructure and improve system reliability.
Emerging Market Trends
One important trend is the use of improved pipe materials designed to provide durability and resistance to challenging operating conditions. PVC, fiberglass, and other engineered materials can offer advantages in selected applications, influencing material selection for new projects.
Digital technologies are also becoming more relevant to sewer infrastructure management. Inspection systems, condition assessment tools, and data-driven maintenance programs can help operators identify deteriorating sections before major failures occur.
Sustainability is another developing theme. Infrastructure planners are increasingly considering lifecycle costs, resource efficiency, and long-term environmental performance when selecting materials and designing wastewater networks.
Competitive Landscape
The competitive environment includes engineering, infrastructure consulting, construction, and wastewater management specialists. Golder Associates, Mott MacDonald, KBR, CH2M Hill, Interflow, Geosyntec, Arcadis, Jacobs, HDR, Black & Veatch, CDM Smith, Tetra Tech, WSP Global, Stantec, and AECOM are among the companies profiled.
Competition is influenced by engineering expertise, project execution capabilities, geographic presence, technical innovation, and relationships with public infrastructure authorities. Companies capable of supporting projects from planning and design through construction and asset management can strengthen their position.
As infrastructure owners increasingly prioritize reliability and lifecycle performance, service providers are expected to emphasize advanced assessment techniques, rehabilitation expertise, and sustainable engineering solutions. These factors should help shape the market through 2035.