Changes

If you are designing a planted system which does infiltrate water, see advice on [[Bioretention: Sizing]].

If you are designing a planted system which does infiltrate water, see advice on [[Bioretention: Sizing]].

The dimensions of a stormwater planter are largely predetermined according to the function of the component. As they do not contain a storage reservoir the planters rely more upon careful selection of materials. Both the filter media and the perforations of the [[Pipe| pipe]] play critical roles for flow control.

The dimensions of a stormwater planter are largely predetermined according to the function of the component. As they do not contain a storage reservoir the planters rely more upon careful selection of materials. Both the saturated hydraulic conductivity of the filter media and the number and size of perforations of the [[underdrain]] pipe play critical roles for flow control. Options for maintaining separation between filter media and clear stone aggregate surrounding the perforated pipe include a 100 mm deep choker layer or sheet of geotextile filter fabric.

{| class="wikitable"

{| class="wikitable"

* 1000 mm to support [[trees]]

* 1000 mm to support [[trees]]

|

|

* 0.35 for Blend A - Drainage rate priority;

* 0.4 for sandier Blend A - Drainage rate priority;

* 0.4 for Blend B - Water quality treatment priority

* 0.35 for more loamy Blend B - Water quality treatment priority

|-

|-

| Pipe diameter reservoir

| Choker layer

| Is equal to underdrain [[pipe]] diameter

| Perforated pipe diameter

| 150 to 200 mm

| 0.4  

| 0.4  

|-

|-

| [[Choker course|Pipe bedding]] (''d_b'')

| Clear stone aggregate layer below perforated pipe

| 50 mm (although commonly omitted altogether).  

| 50 mm (although commonly omitted altogether).  

| 0.4

| 0.4

|}

|}