Project Profile: Major Stormwater Mapping Project Locates Many Previously Unknown Structures

At this point, you are probably very familiar with RJN’s capabilities when it comes to wastewater services, including condition assessments like manhole inspections, smoke testing, dyed water flooding, and building inspections as well as flow monitoring, hydraulic modeling, master planning, SSES, and remediation and design. What you might not know is that RJN can apply our impressive skill set and use of advanced technologies to stormwater systems as well.

For example, over the last three years, RJN has been using advanced technologies to map and assess the condition of the City of San Antonio’s stormwater collection system with stellar results led by RJN’s Stormwater Lead and Project Manager Noelle Gaspard, P.E., GISP, CFM. In fact, RJN has done such a great job with this multi-year project that the City of San Antonio awarded RJN another three-year contract in 2017. The project’s scope will continue the successful mapping and condition assessment efforts optimized during the first three-year project with the addition of developing a Stormwater CCTV and Condition Assessment Master Plan. To learn more about this win, see RJN’s official press release here:

https://www.rjn.com/news-and-events/541-rjn-selected-to-continue-cosa-mapping

What follows is an overview of the multi-year Stormwater System Televising, Mapping and Condition Assessment project initiated by the City of San Antonio in 2015.  This will describe the project and what has been completed thus far while also providing information about technologies used to complete the project, including:

  • Mobile LiDAR for above ground asset identification and survey
  • IBAK Panoramo SI for manhole inspections and condition assessments
  • InfoMaster Sewer to transform the asset inspection data and defect codes into GIS and to conduct the system defect analysis

Scope and Background

Aging stormwater infrastructure is one of the biggest challenges facing communities today. With portions of the City of San Antonio’s stormwater collection system approaching 100 years old, a comprehensive understanding of the condition and location of the existing system was needed.  One of the long-term goals of the City is to integrate its storm system GIS, inspection data, condition assessments, and defect analysis into a comprehensive and easy-to-use stormwater management system. In 2015, the City judiciously initiated a multi-year Stormwater Televising, Mapping and Condition Assessment project – starting with a Pilot Phase Study – and more than 500,000 linear feet of storm pipe has been inspected to date.

The City had two main goals they wanted to accomplish with this project: (1) to complete a thorough field survey, video inspection, and condition assessment of the storm sewer infrastructure and (2) to develop a geospatial database, using GIS, which integrates the storm sewer schematic with all supporting data.  The City selected a pilot area and required that the initial pilot phase of the project be completed with an accelerated timeline of five months.

Challenges and Solutions

Challenge 1:  The City of San Antonio had incomplete knowledge of the location and condition of its stormwater system.

  • Stormwater GIS layers were incomplete and missing key attribute information like pipe size/material/age.
  • Many locations that were known to have stormwater infrastructure were not reflected in the GIS data. In many instances, stormwater inlets and manholes were mapped, yet there were no pipes present in the GIS – and vice-versa – the pipes were mapped without manholes or inlets in the GIS.
  • The condition of the stormwater system was unknown due to lack of inspection data.

Challenge 2: The project was approved by City Council in May 2015 and the Pilot Study had to be completed by the end of the City’s Fiscal Year, September 30, 2015. This only provided RJN five months to complete the outlined scope.

Solution:  The accelerated timeline of five months required efficient data collection and analysis procedures to complete the project within the outlined schedule.  RJN used numerous advanced technologies to locate, map, and assess San Antonio’s stormwater assets, many of which the City had no knowledge of, in a short period of time.

Innovations Employed

RJN and its subconsultant used many cutting-edge technologies to expedite the mapping process and provide more comprehensive and more accurate data. Among these technologies were:

Mobile LiDAR Survey—Once it was recognized that the original count of assets in this area was grossly underestimated due to the incomplete GIS, the scope of the data collection and the amount of assets that needed to be surveyed increased – while the project deadline remained the same. With this increased data collection scope, RJN needed to find a better way to map more assets while staying within the City’s outlined time frame.   A truck-mounted mobile LiDAR (Light Detection And Ranging) system was deployed to scan the entire study area, locate stormwater assets, and document the existing conditions of the above ground system.

The benefits of using this technology were as follows:

  • More efficient— The entire 3.5 square mile study area (more than 54 street miles of data) was surveyed in one day.  This collected 1,000x more data in less than 10% of the time taken for traditional collection methods, which led to reduced field time.
  • Increased safety and decreased traffic impacts—The collection of data via a truck driving at road speeds eliminated traditional surveyor safety issues, kept roads/lanes open, and minimized impact to traffic.  Plus there was no need for two-perosn crews or blocking off street lanes.
  • More data and better data — Millions of survey-grade elevation points were recorded during a continuous drive, which provided accurate location and elevation data for each stormwater asset
  • Improved accuracy—More data points equated to more detailed elevation information. This made it possible to create a digital terrain model for the entire study area that can be used for future two-dimensional hydraulic stormwater modeling by the City.

Manhole Inspection using IBAK Panoramo SI 3D Scanner—Panoramo is a 3D optoscanner used for manhole inspections. The system features two high-resolution digital cameras with distortion-free, wide-angle lenses that scan the manhole interior in a few seconds in a single vertical run, transmitting digital image data to a viewer located in the inspection van.  Unlike a video film from a conventional pan and rotate camera, which only shows the section of view saved at the time of filming, the inspector was able to stop at any position in the manhole and do a 360-degree pan and zoom to take snapshots.  Among the benefits of using the IBAK Panoramo Scanner were:

  • Improved inspection efficiency: —Faster data collection and assessment compared to traditional manhole inspections
  • Improved quality assurance/quality control—Recorded diverse data points that were reviewed and re-inspected at any time to ensure the highest-quality and most accurate and comprehensive reports possible
  • A wide variety of views—A wide variety of views gave RJN experts more thorough and detailed information for analysis, including:
    • Panoramic 360-degree view to interactively view the interior of the manhole to pan and zoom from any angle
    • Unfolded view for measuring observations on the wall of the structure
    • Geometric view to enable precise internal measurements of the structure’s geometry in three-dimensional space with a full point cloud

InfoMaster Sewer for Defect AnalysisRJN used InfoMaster Sewer, developed by Innovyze, to analyze the condition and network connectivity of the storm system. InfoMaster is a complete ArcGIS-based asset integrity management software that leverages existing GIS with enhanced data processing tools and sophisticated predictive analysis to forecast when a water or sewer pipe will fail, helping to determine the most cost-effective solution for avoiding or correcting the problem. Benefits of this tool included:

  • Efficient inspection data processing—This software has built-in tools that streamlined the processing, analysis, and management of the collected field data
  • More comprehensive—Asset condition data and defect codes translated into GIS to show all data spatially, locating problem areas
  • More streamlined—Data mapping and defect analysis visualization enabled clearer understanding of asset conditions
  • Improved quality checks—Multiple data points visually represented allowed the City to see more of its stormwater system at once, catching more problems
  • Simplified CMMS compatibility—Directly integrated with Cartegraph, the City’s CMMS software, as well as other CMMS software platforms

Among the tools used for data delivery and asset management were:

  • ArcGIS
  • PipeLogix
  • InfoMaster Sewer

Impressive Results

Since much of the City’s existing stormwater GIS data was incomplete, this project provided a procedure to accurately inventory the system and understand the condition of the assets. As shown in the following table, much of the stormwater infrastructure was unmapped before the project was initiated and, with the completion of the Pilot Phase, the City now has a better understanding of where the system is located and what condition it is in.

The Pilot Phase of the study bore tremendous fruit for the City by defining a workflow for completing stormwater CCTV, mapping, and condition assessments on a city-wide scale in order to fully understand the location and condition of the stormwater system.  This workflow, developed in the Pilot Phase and refined and optimized during Year 2 and Year 3, outlined the tasks and processes used to efficiently locate storm assets, conduct a CCTV inspection, assess their condition, and subsequently populate the attribute information into the City’s existing PipeLogix, GIS, and Cartegraph databases.

The Pilot Project, Year One (2015), was completed in five months. Year Two (2016) was completed in eight months.  Year Three (2017) is scheduled to be complete in September of 2017.  With the help of advanced technologies, RJN achieved impressive results overall in a short period of time:

Overall, the use of these advanced data collection tools and analysis technologies made it possible to complete the project within the accelerated timeline and provided the City with detailed and useful data deliverables.

Based on these results, the client had this to say about RJN Group, Inc.’s work:

“After listening to us describe our vision for the project and state our goals, the RJN team offered creative approaches that led to results and deliverables that exceeded our expectations. … That allowed us to capture data more quickly and cost-effectively than we thought possible.”

As a result of CoSA’s satisfaction with RJN’s solution-oriented approach and positive progress with the stormwater mapping project, RJN secured another three-year contract to continue the successful mapping and condition assessment efforts.  In summary, RJN engineers are specialists in wastewater collection system improvements, but we also possess the capabilities and skills necessary in solving problems with stormwater system issues as well.