Case Study

Automating the Wastewater Treatment Design Process in Arizona

Transcend and Stanley Consultants Case Study for a 1MGD Wastewater Resource Recovery Facility in Arizona.



Related Topics

Wastewater Treatment

I&I Detection


The Pinewood Sanitary District (PSD) in Arizona suffered from high volumes of Inflow and Infiltration (I&I) at their 1MGD wastewater resource recovery facility. Additionally, there were concerns about the performance of their Influent Screens and Aerobic Digester. The intermittent I&I issues caused periodic violations of the facilities existing NPDES Permit.


Working with the Transcend Design Generator (TDG), Stanley Consultants was able to automatically ascertain the appropriate sizing requirements for a new Flow Equalization Basin and an expansion to the existing Aerobic Digester. Additionally, Stanley Consultants was able to confirm that other treatment process units were adequately designed and sized.


  • Using TDG compressed the timeframe to run three separate process calculations from 5 days to 1 day, thereby saving the client money and completing the project on time.
  • Due to the success of using TDG on this project, Stanley Consultants is currently using the software on additional projects for other clients.
  • The TDG outputs supported Stanley Consultants rigorous standards for high quality engineering documentation and yielded a branded and formatted professional design package.


  • Stanley Consultants ran TDG to automatically assess three process scenarios.
  • Ultimately, the Plant Permitted Capacity is what was required
    to meet current Arizona regulatory requirements.
  • It was determined that the high I&I flow had to be neutralized
    using a Flow Equalization Basin
    adequately sized to mitigate the periodic plant process upsets.
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