Key Takeaways

• GIS-based sewer mapping creates a digital, map-based view of pipes, manholes, basins, and other collection system assets.
• When GIS data is connected to inspections, acoustic assessments, I&I monitoring, and digital twin tools, it becomes a practical decision-support system.
• Utilities can use GIS mapping to prioritize cleaning, target rehabilitation, reduce inflow and infiltration, and support regulatory reporting.
• A strong sewer GIS depends on accurate asset IDs, reliable field data, standardized attributes, and clear risk scoring.
• RH Borden helps wastewater agencies turn sewer system data into actionable maps that guide smarter maintenance and capital planning.

Wastewater collection systems are under more pressure than ever. Aging infrastructure, tighter regulatory requirements, and limited staff time make it harder for utilities to see exactly what is happening underground. Traditional paper maps and ad hoc GIS layers were never designed to support modern, data-driven asset management.

GIS-based sewer mapping changes that. By bringing your entire collection system into a centralized, spatial database, you can finally connect field data, inspection results, and hydraulic performance in one place. The result is better decisions, fewer surprises, and a stronger justification for every dollar you spend.

What Is GIS-Based Sewer Mapping?

Geographic Information System (GIS)-based sewer mapping is the process of building and maintaining a digital, map-based representation of your entire collection system. Instead of relying on paper as-builts or disconnected spreadsheets, GIS organizes each asset as a data-rich feature on a map.

In a typical GIS-based sewer map, you can see:

• Pipes – location, diameter, material, slope, and installation year
• Manholes – coordinates, rim and invert elevations, condition scores, and access details
• Basins and sub-basins – service areas, contributing flows, and priority zones
• Critical facilities – pump stations, overflows, and downstream treatment plants

Each feature is tied to an attribute table, so you can filter, sort, and analyze your system based on age, material, risk, or any other criteria that matter to your team.

How GIS Sewer Mapping Fits with Digital Twin Technology

On its own, GIS-based sewer mapping is a powerful way to organize system data. When you combine GIS with modern sensing and digital twin technology, it becomes a living model of your network.

For example, RH Borden helps agencies move beyond static maps by incorporating:

• Acoustic assessment results – to quickly identify where pipes are likely blocked or restricted.
• Manhole Virtual Models (MVMs) – digital twins of each manhole that quantify structural condition and guide rehab planning.
• High-density I&I monitoring data – sensor networks that show exactly where rain-derived inflow and infiltration is entering the system.

When these datasets are tied back to GIS, you are not just looking at lines on a map. You are looking at the real-world performance and condition of each segment of your collection system, in a format that supports confident, defendable decisions.

Key Components of a GIS-Based Sewer Map

Building a useful GIS map is about more than digitizing old plans. The most effective programs focus on a few core components from the start:

1. Accurate, Georeferenced Asset Inventory

The foundation of GIS is a reliable inventory of pipes, manholes, and related structures. That means confirming:

• Correct pipe alignments and connectivity between upstream and downstream assets
• Accurate coordinates for manholes and appurtenances
• Verified diameters, materials, and installation dates wherever possible

Missing or incorrect attributes can be filled in over time as field crews perform inspections or maintenance. The important thing is that every asset has a unique ID and a place on the map.

2. Standardized Attribute Fields

Consistent data fields make it possible to compare assets and run system-wide queries. Standardizing fields for condition scores, inspection dates, rehab history, and risk ratings keeps your map from turning into just another silo.

For example, utilities often track:

• Last cleaning date and method
• Last CCTV or acoustic assessment
• Known defects or recurring maintenance issues
• Proximity to sensitive receptors such as schools, waterways, or hospitals

3. Integration with Field Data Collection

Modern GIS-based programs connect directly to field tools so that new information flows smoothly back into the map. Tablets, GPS receivers, acoustic assessment equipment, and manhole scanning tools can all be configured to write data into the same asset IDs your GIS uses.

That integration reduces manual data entry, improves accuracy, and gives supervisors near real-time visibility into what is happening across the system.

How GIS-Based Sewer Mapping Improves Decision-Making

Once your map is populated with reliable data, it becomes a decision support tool instead of just a record of where assets are buried. Here are some of the most common ways utilities use GIS to make better choices.

Prioritizing Cleaning and Maintenance

GIS lets you quickly identify which pipes and basins truly need attention. By combining acoustic assessment results, past blockage history, and criticality (for example, pipes near schools or waterways), you can target cleaning resources where they will have the most impact.

Instead of cleaning the same segments on a fixed schedule, you can shift to condition-based maintenance. That means fewer truck rolls, reduced overtime, and more capacity for proactive work.

Targeting I&I Reduction Investments

Inflow and infiltration reduction is only effective when you know where the water is actually entering the system. GIS-based sewer mapping allows you to overlay flow monitoring data, rainfall information, and basin boundaries to pinpoint problem areas.

With that insight, you can direct CCTV inspections, smoke testing, or rehabilitation to the locations that will deliver the biggest reduction in wet-weather flows and overflow risk.

Planning Capital Improvements and Rehab

Capital planning decisions are easier to defend when they are grounded in spatial data. GIS helps you build risk-based renewal programs by combining condition scores, consequence of failure, and cost estimates in one view.

Decision-makers can see which neighborhoods will benefit, how proposed projects align with regulatory drivers, and what happens if a project is deferred. That supports more transparent, data-driven conversations with boards, councils, and the public.

Supporting Regulatory Compliance and Reporting

Regulators increasingly expect agencies to demonstrate control over their collection systems. GIS-based maps make it easier to document where overflows have occurred, what corrective actions were taken, and how future risk is being reduced.

Because assets, work orders, and inspection results are tied together spatially, you can quickly generate maps and reports that show progress over time.

Improving Communication Across Departments

Finally, GIS creates a common language for operations, engineering, and management. Everyone is looking at the same map, using the same asset IDs, and drawing on the same data.

That shared view reduces misunderstandings and helps cross-functional teams align around priorities. It also makes it easier to onboard new staff, who can quickly see how different parts of the system connect.

Practical Steps to Get More from Your Sewer GIS

If you already have some GIS data in place, you do not need to start from scratch. A few focused steps can dramatically increase the value of your existing map.

• Validate and fill gaps – confirm key attributes for high-risk areas first, then expand outward.
• Connect inspection and maintenance data – ensure each work order or inspection refers to a GIS asset ID.
• Standardize condition and risk scoring – adopt consistent rating scales so you can compare basins and assets.
• Visualize priorities – use symbology and dashboards to highlight pipes and manholes that warrant attention.

For many agencies, partnering with a team that specializes in digital twin technology and wastewater collection systems is the fastest way to move from static maps to actionable intelligence.

How RH Borden Can Help

RH Borden focuses exclusively on helping wastewater agencies modernize collection system maintenance using digital tools. Our team combines GIS expertise with field-proven technologies such as acoustic assessments, Manhole Virtual Models, and basin-scale I&I monitoring.

By tying these datasets back into your GIS, we help you:

• Build a complete, accurate map of your sewer network
• Identify which pipes and manholes truly need attention
• Direct rehab dollars to the highest-return projects
• Document improvements and support regulatory compliance

If you would like to see how GIS-based sewer mapping and digital twin technology could work in your system, we are here to help.

Ready to get more from your sewer GIS? Contact RH Borden to schedule a conversation with our team.

FAQs About GIS-Based Sewer Mapping

1. What does GIS stand for in sewer mapping?

GIS stands for Geographic Information System. In sewer mapping, it refers to a digital map and database that stores the location, attributes, and history of collection system assets such as pipes, manholes, pump stations, basins, and service areas.

2. How is GIS-based sewer mapping different from a paper map?

A paper map shows where assets are located, but a GIS map can also store data about each asset, including material, age, size, condition, inspection history, maintenance records, and risk level. That makes GIS useful for analysis, reporting, planning, and day-to-day decision-making.

3. Can GIS mapping help reduce inflow and infiltration?

Yes. GIS mapping can connect flow monitoring, rainfall, basin boundaries, and inspection data so utilities can identify where I&I is most likely entering the system. This helps agencies focus testing and rehabilitation where it will have the greatest impact.

4. What data should be included in a sewer GIS map?

At minimum, a sewer GIS map should include pipes, manholes, basins, pipe diameter, material, slope, installation year, invert elevations, and asset IDs. More advanced systems also include inspection results, acoustic assessment data, condition scores, cleaning history, I&I monitoring data, and rehabilitation records.

5. How does GIS-based sewer mapping support better capital planning?

GIS helps utilities compare asset condition, likelihood of failure, consequence of failure, and project costs spatially. This allows staff to prioritize rehabilitation projects based on risk and return on investment instead of relying only on age, complaints, or anecdotal field experience.