Things that Happened Before You were Born (The earth and SWMM were created) a story by Dr. Larry A. Roesner, Ph.D.,P.E. based (loosely*) on biblical quotes and his own bigger than life experiences *Actually very loosely

The earth and SWMM parallels In the beginning, there was the Rational Method t1t1 t2t2 t3t3 Rain over duration, Σ t Time of concentration, Σ t Q peak = C·I · A

The earth and SWMM parallels And darkness covered the drainage world because of the limited applicability of the Rational Method

Then forward looking engineers said “let there be light” And so, they created more rational models SCS TR20 and TR55 SCS TR20 and TR55 HEC-1,2,3,4,5,6, and RAS HEC-1,2,3,4,5,6, and RAS SWMM SWMM The earth and SWMM parallels

SCS Method accounts for initial soil moisture and time varying C SCS Method accounts for initial soil moisture and time varying C Runoff hydrographs can be computed Runoff hydrographs can be computed The earth and SWMM parallels Runoff Rainfall Increasing Imperviousness

HEC model produces runoff hydrograph from rainfall hyetograph using unit hydrograph technique ( Who knows the Schneider coefficient for a 30% pervious urban area? ) HEC model produces runoff hydrograph from rainfall hyetograph using unit hydrograph technique ( Who knows the Schneider coefficient for a 30% pervious urban area? ) Hydrologic routing produces channel flows Hydrologic routing produces channel flows Hec 2 computes steady state backwater through maximum discharge profile Hec 2 computes steady state backwater through maximum discharge profile The earth and SWMM parallels

SWMM was to be the mother of all models SWMM was to be the mother of all models It would trace runoff from its point of origin, through the stormwater system to and through the receiving waters, computing flows and water levels It would trace runoff from its point of origin, through the stormwater system to and through the receiving waters, computing flows and water levels It would trace wet weather pollution from its point of origin to its final fate in the receiving waters It would trace wet weather pollution from its point of origin to its final fate in the receiving waters The earth and SWMM parallels

Concept of SWMM RECEIVE EXTRAN TRANSPORT RUNOFF Rainfall hyetograph Watershed Data Q (t) C(t) Q (t) C(t) Q (t) Transport System Data Transport System Data Receiving Water System Data Point Source Loads Inlets Outfalls Q (t), C(t) in Receiving Water

And so they rested, And so it was, and (most) Civil Engineers saw the models and they were good. for 30yrs!!? The earth and SWMM parallels

SWMM Runoff Module I f(t) S W S R f(t) Q (t)

SWMM Extran Module

INTRODUCTION TO SWMM AND MIKE SWMM CE 580 Analysis of Urban Water Systems Session 10 – Sept 25, 2000

SWMM Computer Program Layout

Interrelationship of the SWMM Blocks

SWMM Schematic

MIKE SWMM Demonstration

This presentation is an embellishment of the road culvert example contained in the Mike SWMM documentation. In order to see the results of road overtopping, the weirs at nodes 110 and 60 have been changed to box conduits. Three simuations were performed: o The "existing" condition: File name Exam11e.dat - culvert 110 diameter = 1.0 ft - culvert 60 diameter = 3.0 ft o The "existing" condition: File name Exam11p1.dat - culvert 110 diameter = 2.0 ft - culvert 60 diameter = 3.5 ft o The "existing" condition: File name Exam11p2.dat - culvert 110 diameter = 4.0 ft - culvert 60 diameter = 5.0 ft The first simulation shows severe overtopping of the road at both location, with prolonged backwater at junction 110. The second simulation shows much improvement, and the third simulation shows the problem fixed except for a small 15 minute overtopping of the the road at junction 110. Modifications by LAR 12/2/98

Camp Dresser & McKee Danish Hydraulic Institute The power of two...

Danish Hydraulic Institute - a Consulting and Research Organization Objectives: Objectives: to develop and apply advanced methods and technologies to develop and apply advanced methods and technologies within hydraulic and hydrological engineering within hydraulic and hydrological engineering to provide specialised consulting services to provide specialised consulting services to contribute to the technological development through to contribute to the technological development through international research collaboration and through international research collaboration and through transfer of know-how and technology transfer of know-how and technology

MIKE SWMM

MIKE 11 1-D modeling system for rivers and channels 1-D modeling system for rivers and channels HD, AD, WQ, ST, FF, GIS HD, AD, WQ, ST, FF, GIS more than 400 users world-wide more than 400 users world-wide

MIKE 21 a modelling system for estuaries, coastal waters and seas a modelling system for estuaries, coastal waters and seas more than one hundred users in 35 countries more than one hundred users in 35 countries

MIKE SHE an integrated hydrological modeling system an integrated hydrological modeling system 3-D Groundwater movement, unsaturated zone, Solute transport, dynamic link to MIKE 11 3-D Groundwater movement, unsaturated zone, Solute transport, dynamic link to MIKE 11 some 50 users in 10 countries some 50 users in 10 countries

MIKE BASIN Water Master Planning Water Master Planning use of available water resources use of available water resources planning for future water developments planning for future water developments GIS GIS defining the network defining the network evaluating results evaluating results integrated analysis with spatial data integrated analysis with spatial data

LITPACK an integrated modelling system for Littoral Processes And Coastline Kinetics an integrated modelling system for Littoral Processes And Coastline Kinetics more than 60 users in 20 countries more than 60 users in 20 countries

MIKE SWMM Demonstration

Top of Bank Top of Overbank Culvert

Junction 110Junction 60 Road Culvert RoadCulvert Road Elev.

Junction 110 Road Culvert Road Elev.

Junction 110 Road Culvert Road Elev.

Junction 110 Road Culvert Road Elev.

Junction 110 Road Culvert Road Culvert Road Elev. Junction 60

Questions?