Permeable Design Pro

Design permeable interlocking pavements with Permeable Design Pro (PDP):

  • Integrates hydrologic and structural solutions.
  • Includes rainfall data for 12 major cities in South Africa.
  • Provides base thickness solutions from calculating inflow/outflow & traffic loads.
  • Design sustainable storm water management with PICPs.
  • Design solutions with CAD cross section outputs.

The Permeable Design Pro (PDP) software application is used to develop permeable aggregate base and subbase thickness solutions for supporting traffic loads, and for water storage and infiltration. By integrating both hydrologic and structural solutions, PDP helps to ensure the intended performance of permeable paving systems.

PDP was developed to assist civil engineers and landscape architects to design permeable interlocking concrete pavements (PICP). The application enables the user to design PICPs for numerous applications, such as, residential driveways, commercial walkways and parking lots, paved roads, as well as industrial paving applications.

Permeable Design Pro includes rainfall data for 12 major South African cities, extensive documentation and help library, on-screen mouse-over advice, as well as input error-trapping for learners.

PDP is available for purchase and download from, or alternatively it can be made available through Bosun.

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  • Characterise run-on volumes from adjacent areas and roofs into PICP with Curve Numbers.
  • Reference an extensive library of 24-hour rainfall depths for 12 major South African cities up to 100-year events.
  • Analyse infiltration and outflow from the library of rainfall depths, or user-supplied rainfall depths.
  • Use program default values for soil subgrade strengths and infiltration rates, or input user-supplied data.
  • Design for no infiltration for detention or water harvesting, or for partial or full infiltration into the soil subgrade.
  • Analyse base/subbase thickness requirements for vehicular applications up to 1 million ESALs (Caltrans TI = 9)
  • Model infiltration and outflow from 1 to 7 days inclusive of the design rainfall event.
  • Conduct outflow sensitivity analysis using various underdrain layout, slopes and elevations on low infiltration soils.
  • Calculate storage volumes and outflow rates, Curve Numbers and coefficients of runoff.
  • Account for residual water depths stored in the base/subbase from antecedent rain events in low infiltration soils
  • Saving/printing input/output hydrographs, summary reports and CAD drawing (dwg) of PICP cross section designs

Software Inputs & Outputs

Inputs Output
  • Site configuration – contributing drainage area and surface(s), slope, curve numbers and roughness.
  • Library of SCS-type rainfall events (2, 5, 10, 25, 50, 100-year) for 12 major South African cities. (included).
  • Optional user-provided rainfall events.
  • Traffic loads (ESALs) for parking lots or streets.
  • Soil strength (MR, CBR or R-value) and infiltration rate.
  • Base/subbase aggregate gradations.
  • Underdrain(s) diameter, slope and spacing.
  • Antecedent rainfall depths within the subbase.
  • Base/subbase porosity and thicknesses based on storage hydrograph flows.
  • Storage and outflow volumes.
  • Curve numbers and runoff coefficients.
  • Structural subbase thickness up to 1 million ESALs.
  • CAD output cross section of design solutions with/without underdrains, exportable to project drawings.
  • Print or save input/output reports as a pdfs and numeric hydrographs as Excel files.

Details & Requirements

  • License purchased is for Permeable Design Pro V2.0 / V3.0.
  • Automatic updates provided complimentary.
  • Permeable Design Pro will automatically check for updates upon start-up and prompt you to download/install through an automated installation process.
  • For individual use.
  • Compatible with machines only running any edition of Windows 7, Windows 8 or Windows 10.