Optimizing a SuDS analysis

Transcript

00:03

Once you have modeled a fully featured drainage system with suds,

00:07

you are ready to simulate how they operate during rainfall events.

00:12

On the ribbon

00:13

analysis tab analysis panel click validate

00:17

in this example. No errors are listed

00:21

click OK

00:23

in the criteria panel select analysis criteria

00:27

in the analysis criteria dialog.

00:30

Make sure the parameters are set as they appear in this example.

00:33

And then click OK

00:36

in the analysis panel, select go to run the analysis.

00:40

Once the simulation is complete,

00:42

the storm water controls summary dialog opens.

00:46

In this example,

00:47

the dialogue shows the results of the 1st 15 minute summer storm

00:52

realise that there are a total of 18 storms

00:55

that were used throughout the creation of this model.

00:58

Click critical storm

00:60

to see how each stormwater control feature handles the most severe rainfall event.

01:06

You should see that three different storms were the

01:08

critical duration for the three storm water controls.

01:12

The percentage available column shows the percentage

01:15

of the total volume of the stormwater

01:17

control available above the maximum water elevation

01:21

measured to the exceed its elevation.

01:24

A negative value shows that the capacity

01:26

of the storage structure has been exceeded.

01:29

In this example, you can see that the pond has 39% of its capacity available.

01:35

This is not surprising because the introduction of the two

01:38

sub structures has reduced the flow rate into the pond

01:42

and you will now be able to reduce its size substantially.

01:46

The swell is at -5%, meaning that it is a little undersized.

01:50

However, the size of this whale is fixed.

01:53

So you need to think about this in a different way.

01:56

You need to increase the discharge rate from

01:58

the Swail so that its capacity is acceptable.

02:02

You can apply a similar approach to the cellular storage.

02:05

It is currently at plus 8%

02:07

so it's passed forward rate can be reduced a little

02:11

once you have optimized the upstream suds you will reassess the pond

02:16

before you optimize your suds features.

02:19

Best practice is to create a new phase

02:22

in the tree view.

02:23

Under the phase management node,

02:25

right click the suds design phase and select duplicate phase.

02:30

Right click the new phase you created and click rename phase.

02:35

In this example the name optimized

02:37

design is entered.

02:40

Press enter when you have finished naming the new phase

02:42

and make sure to deactivate all other phases by

02:45

tunneling off the lightbulb icons next to them,

02:48

leaving the new phase as the only one visible.

02:52

Also make sure they are all set to stop so that only the optimized

02:56

design is set to go and will be analyzed.

03:00

You will first optimize the cellular storage structure.

03:04

Double click its icon to view its properties

03:08

in the outlets.

03:08

Tab open the diameter calculator and decreased the

03:12

design flow from nine liters per second to seven

03:16

Giving a diameter of 58 mm

03:19

click OK.

03:21

In reality it could take you a few iterations or guesses to get to

03:25

the correct pass forward rate but in this case it has been done for you

03:31

apply the same principle to the swales,

03:33

increase the orifice flow to 5.7 liters per second

03:38

Giving a diameter

03:40

of 52 mm.

03:43

In the ribbon

03:44

analysis tab analysis panel,

03:47

click go to run a simulation.

03:50

When the storm water controls summary opens,

03:53

click critical storm and view the percentage available column

03:58

In this example,

03:59

the Swail and cellular storage capacities are

04:01

now optimized to within 2% of capacity

04:04

but the pond is on 39%

04:06

and therefore needs further optimization.

04:10

The stormwater control summary shows that the maximum resident

04:13

volume in the pond is 485 m cubed.

04:17

A top tip is to size the pond slightly smaller than this value.

04:23

In this case it was determined that 385 m cubed

04:26

is the right size for the pond

04:29

with the select tool. Active

04:31

double click the pond icon to open its properties.

04:35

The Dialogue lists a total volume of 795.059 m3

04:42

Open the Sivass calculator and enter a new volume of 385 m3.

04:48

Click OK.

04:50

The pond size changes in the preview window of the pond. Dialogue

04:55

click OK.

04:56

And you see the pond shrink in the plan view.

04:59

Keep in mind that when resizing a pond it may shrink to

05:02

the point that the connection icons fall outside of its boundary,

05:06

in which case they would have to be repositioned

05:11

to make sure all connections were maintained during the optimization process.

05:15

Use a flow path

05:17

in the tree view,

05:19

right click flow paths and select add

05:22

Click Manhole S. 1 to set a start point

05:25

and then click Manhole S. 17 to set an end point.

05:30

In this example,

05:31

the flow path reveals no broken connections.

05:35

You could also right click the new flow path

05:37

and select show profile to see the complete long section

05:42

with the flow path still highlighted

05:44

in the analysis. Tab analysis panel click validate.

05:49

No errors are listed so click Okay.

05:53

Run the simulation again.

05:55

When the storm water control summary opens, click critical storm

05:59

and find the percentage available column.

06:02

There is 0% available but the status is okay.

06:07

The maximum resident volume is 384 m cubed, so less than one m cubed is available.

06:14

In reality you may need to increase the size of the pond slightly,

06:18

but for this exercise

06:19

it is perfectly optimized

Video transcript

00:03

Once you have modeled a fully featured drainage system with suds,

00:07

you are ready to simulate how they operate during rainfall events.

00:12

On the ribbon

00:13

analysis tab analysis panel click validate

00:17

in this example. No errors are listed

00:21

click OK

00:23

in the criteria panel select analysis criteria

00:27

in the analysis criteria dialog.

00:30

Make sure the parameters are set as they appear in this example.

00:33

And then click OK

00:36

in the analysis panel, select go to run the analysis.

00:40

Once the simulation is complete,

00:42

the storm water controls summary dialog opens.

00:46

In this example,

00:47

the dialogue shows the results of the 1st 15 minute summer storm

00:52

realise that there are a total of 18 storms

00:55

that were used throughout the creation of this model.

00:58

Click critical storm

00:60

to see how each stormwater control feature handles the most severe rainfall event.

01:06

You should see that three different storms were the

01:08

critical duration for the three storm water controls.

01:12

The percentage available column shows the percentage

01:15

of the total volume of the stormwater

01:17

control available above the maximum water elevation

01:21

measured to the exceed its elevation.

01:24

A negative value shows that the capacity

01:26

of the storage structure has been exceeded.

01:29

In this example, you can see that the pond has 39% of its capacity available.

01:35

This is not surprising because the introduction of the two

01:38

sub structures has reduced the flow rate into the pond

01:42

and you will now be able to reduce its size substantially.

01:46

The swell is at -5%, meaning that it is a little undersized.

01:50

However, the size of this whale is fixed.

01:53

So you need to think about this in a different way.

01:56

You need to increase the discharge rate from

01:58

the Swail so that its capacity is acceptable.

02:02

You can apply a similar approach to the cellular storage.

02:05

It is currently at plus 8%

02:07

so it's passed forward rate can be reduced a little

02:11

once you have optimized the upstream suds you will reassess the pond

02:16

before you optimize your suds features.

02:19

Best practice is to create a new phase

02:22

in the tree view.

02:23

Under the phase management node,

02:25

right click the suds design phase and select duplicate phase.

02:30

Right click the new phase you created and click rename phase.

02:35

In this example the name optimized

02:37

design is entered.

02:40

Press enter when you have finished naming the new phase

02:42

and make sure to deactivate all other phases by

02:45

tunneling off the lightbulb icons next to them,

02:48

leaving the new phase as the only one visible.

02:52

Also make sure they are all set to stop so that only the optimized

02:56

design is set to go and will be analyzed.

03:00

You will first optimize the cellular storage structure.

03:04

Double click its icon to view its properties

03:08

in the outlets.

03:08

Tab open the diameter calculator and decreased the

03:12

design flow from nine liters per second to seven

03:16

Giving a diameter of 58 mm

03:19

click OK.

03:21

In reality it could take you a few iterations or guesses to get to

03:25

the correct pass forward rate but in this case it has been done for you

03:31

apply the same principle to the swales,

03:33

increase the orifice flow to 5.7 liters per second

03:38

Giving a diameter

03:40

of 52 mm.

03:43

In the ribbon

03:44

analysis tab analysis panel,

03:47

click go to run a simulation.

03:50

When the storm water controls summary opens,

03:53

click critical storm and view the percentage available column

03:58

In this example,

03:59

the Swail and cellular storage capacities are

04:01

now optimized to within 2% of capacity

04:04

but the pond is on 39%

04:06

and therefore needs further optimization.

04:10

The stormwater control summary shows that the maximum resident

04:13

volume in the pond is 485 m cubed.

04:17

A top tip is to size the pond slightly smaller than this value.

04:23

In this case it was determined that 385 m cubed

04:26

is the right size for the pond

04:29

with the select tool. Active

04:31

double click the pond icon to open its properties.

04:35

The Dialogue lists a total volume of 795.059 m3

04:42

Open the Sivass calculator and enter a new volume of 385 m3.

04:48

Click OK.

04:50

The pond size changes in the preview window of the pond. Dialogue

04:55

click OK.

04:56

And you see the pond shrink in the plan view.

04:59

Keep in mind that when resizing a pond it may shrink to

05:02

the point that the connection icons fall outside of its boundary,

05:06

in which case they would have to be repositioned

05:11

to make sure all connections were maintained during the optimization process.

05:15

Use a flow path

05:17

in the tree view,

05:19

right click flow paths and select add

05:22

Click Manhole S. 1 to set a start point

05:25

and then click Manhole S. 17 to set an end point.

05:30

In this example,

05:31

the flow path reveals no broken connections.

05:35

You could also right click the new flow path

05:37

and select show profile to see the complete long section

05:42

with the flow path still highlighted

05:44

in the analysis. Tab analysis panel click validate.

05:49

No errors are listed so click Okay.

05:53

Run the simulation again.

05:55

When the storm water control summary opens, click critical storm

05:59

and find the percentage available column.

06:02

There is 0% available but the status is okay.

06:07

The maximum resident volume is 384 m cubed, so less than one m cubed is available.

06:14

In reality you may need to increase the size of the pond slightly,

06:18

but for this exercise

06:19

it is perfectly optimized

Video quiz

Step-by-step:

Once you have modeled a fully featured drainage system with SuDS, you are ready to simulate how they operate during rainfall events.

On the ribbon, Analysis tab, Analysis panel, click Validate.
In the Validate dialog box, verify there are no errors.
Close the dialog box.
On the ribbon, select Analysis Criteria.
In the Analysis Criteria dialog box, make sure the parameters are set as they appear in this example:
Click OK.
To run the analysis, on the ribbon, Analysis tab, Analysis panel, click Go.

Once the simulation is complete, the Stormwater Controls Summary dialog box opens. In this example, it shows the results of the first 15-minute summer storm. Realize that there are a total of 18 storms that were used throughout the creation of this model.

In the Stormwater Controls Summary, click Critical Storm to see how each stormwater control feature handles the most severe rainfall event.

In this example, three different storms were the critical duration for the three stormwater controls.

The Percentage Available (%) column shows the percentage of the total volume of the Stormwater Control available above the maximum water elevation measured to the exceedance elevation. A negative value shows that the capacity of the storage structure has been exceeded. Here, the pond has 39% of its capacity available. This is not surprising, because the introduction of the two SuDS structures to this model has reduced the flow rate into the pond. Now, you will be able to reduce its size substantially.

The swale is at minus 5%, meaning that it is a little undersized. However, the size of the swale is fixed, so instead, you need to increase the discharge rate from the swale so that its capacity is acceptable.

You can apply a similar approach to the cellular storage. It is currently at plus 8%, so its pass forward rate can be reduced a little.

Once you have optimized the upstream SuDS, you can reassess the pond.

Best practice is to create a new phase for the SuDS optimization:

In the Tree View, under the Phase Management node, right-click the SuDS design phase and select Duplicate Phase.
Right-click the new phase and click Rename Phase.
Rename it, “Optimized SuDS Design”.
Deactivate all other phases by toggling OFF the light bulb icons next to them, leaving the new phase as the only one visible.
Set all other phases to Stop, so that only the optimized suds design is set to Go.
Double-click the Cellular Storage icon to view its properties.
In the Cellular Storage dialog box, Outlets tab, open the Diameter Calculator.
Decrease the Design Flow to 7 liters per second.
Click OK.

Note that, back in the Cellular Storage dialog box, a new Diameter of 58 mm was calculated.

Double-click the Swale icon to open its properties.
In the Swale dialog box, Outlets tab, open the Diameter Calculator.
Increase the Design Flow (orifice flow) to 5.7 l/s.
The Diameter should have changed automatically to 52 mm. Click OK.
To run a simulation, in the ribbon, Analysis tab, Analysis panel, click Go.
When the Stormwater Controls Summary opens, click Critical Storm.
View the Percentage Available (%) column.

In this example, the swale and cellular storage capacities are now optimized to within 2% of capacity, but the pond is on 39% and therefore needs further optimization.

The Stormwater Controls Summary shows that the maximum resident volume in the pond is 485 meters cubed. A top tip is to size the pond slightly smaller than this value. In this case, it was determined that 385 meters cubed is the right size for the pond.

Double-click the Pond icon to open its properties.
Open the Sizing Calculator.
Enter a new Volume of 385 cubic meters.
In the Tree View, right-click Flow Paths and select Add.
Click manhole S1 to set the start point.
Click manhole S17 to set the endpoint.

In this example, the flow path reveals no broken connections.

Right-click the new flow path and select Show Profile to see the complete long section.
With the flow path still highlighted, on the ribbon, Analysis tab, Analysis panel, click Validate.
In the Validate dialog box, verify that there are no errors.
Click OK to close the dialog box.
On the ribbon, click Go to run the simulation.
In the Stormwater Controls Summary, click Critical Storm.
Review the Percentage Available (%) column.

There is zero percent available, but the Status is OK. The maximum resident volume is 384 meters cubed, so less than 1 meter cubed is available. In reality, you may need to increase the size of the pond slightly, but for this exercise, it is perfectly optimized.

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Optimizing a SuDS analysis

Video quiz

After running an analysis on your SuDS design, in the Stormwater Controls Summary, which reported value for the critical storm tells you whether each feature is optimal or not in its current design?

Step-by-step: