By NORMA Group
Catch Basins Frequently Asked Questions
A majority of the catch basins, Spee-D basins, risers, and catch basin universal outlets are made from styrene. The 9 in. catch basins (NDS part numbers 900 & 900-4) and 12 in. catch basins (1200NGB, 1200, 1203, & 1204) are made from polypropylene. The 18 in. catch basin (1882 & 1884), 24 in. catch basin (2400 & 2404), 24 in. catch basin riser (2418), and universal outlet for the 24 in. catch basin (2410) are made from HDPE.
No, a catch basin universal outlet must be used to connect pipes to the catch basins. Outlet adapters work with the catch basin outlet opening to accommodate pipe connection and provide a secure, soil-tight connection to drain pipe with no tape or glue required. They're made to fit the keyed opening in the catch basin and lock in place. NDS offers a variety of outlet adapters; choose the appropriate adapter to fit the catch basin and drain pipe. Learn more about Catch Basin Universal Outlets.
- The 3 in. & 4 in. Universal Locking Outlet (#1243) fits 3 in. & 4 in. Corrugated Pipe, 3 in. & 4 in. Sewer & Drain Pipe, 4 in. Sch. 40 Pipe, and 3 in. & 4 in. Triple Wall Pipe. The Locking Outlet snaps on to most 3 in. and 4 in. corrugated pipe. Use it with 9 in., 12 in., 18 in. and 24 in. Catch Basin Series and #930, #1230, #1830 and #2410 Adapters. Using it with the 24 in. Catch Basin also requires a #2410 Adapter.
- The 3 in. & 4 in. Offset Universal Outlet (#1245) fits 3 in. & 4 in. Corrugated Pipe, 3 in. & 4 in. Sewer & Drain Pipe, 4 in. Sch. 40 Pipe, and 4 in. Triple Wall Pipe. It allows for adjusting the inlet height. Use it with 9 in., 12 in., 18 in. and 24 in. Catch Basin Series. Using it with the 24 in. Catch Basin also requires a #2410 Adapter.
- The 6 in. Universal Locking Outlet (#1266) fits 6 in. Sewer & Drain Pipe and 6 in. Corrugated Pipe. Use it with 9 in., 12 in., 18 in. and 24 in. Catch Basin Series and #930, #1230 and #1830 Low-Profile Adapters. Using it with the 24 in. Catch Basin also requires a #2410 Adapter.
- The 8 in. Universal Outlet (#1888) fits 8 in. Sewer & Drain Pipe and 8 in. Corrugated Pipe. Use it with the 18 in. and 24 in. Catch Basin Series. Using it with the 24 in. Catch Basin also requires a #2410 Adapter.
- The 8 in. Offset Universal Adapter (#1889) fits 8 in. Sewer & Drain Pipe and 8 in. Corrugated Pipe. Use it with 12 in. and most 18 in. Catch Basin Series (except the 1800 and 1804).
- The 10 in & 12 in. Universal Adapter (#2410) comes with an Outlet Reducer Ring (1890) pre-inserted and fits 10 in. and 12 in. Sewer & Drain Pipe; 10 in. and 12 in. Dual Wall Corrugated Pipe; and 12 in. Single Wall Corrugated Pipe (NOTE: it does not fit 10 in. Single Wall Corrugated Pipe). It reduces the opening to fit most 3 in. to 8 in. adapters above (all except the #1889) for use with 3 in., 4 in., 6 in. and 8 in. Sewer & Drain Pipe; 3 in., 4 in., 6 in. and 8 in. Corrugated Pipe; and 4 in. Sch. 40 Pipe (select corresponding adapter above).
The universal outlets are designed to fit a variety of pipe types and pipe sizes. If the connection between the pipe and the outlet is loose, apply a bead of waterproof silicone to both the pipe and the outlet and then connect the two. The silicone will hold the pieces together and create a waterproof seal.
The table below shows which universal outlets connect to which catch basin:
| Outlet | 9 inch | 12 inch | 18 inch | 24 inch |
|---|---|---|---|---|
| 1242 | ✅ | ✅ | ||
| 1243 | ✅ | ✅ | ||
| 1245 | ✅ | ✅ | ||
| 1266 | ✅ | ✅ | ||
| 1888 | ✅ | |||
| 1889 | ✅* | |||
| 2410 |
✅ |
* NOTE: The 1889 offset adapter will connect, but only in 2 of the 4 possible offset directions.
When coupled with the 1890 Universal Outlet Reducer Ring, the following outlets will connect to the 18 in. catch basin: 1242, 1243, 1245, 1266, & 1889. When coupled with the 2410 Universal Adapter (comes with an 1890 Reducer Ring), all outlets except for the 1889 can be connected to the 24 in. catch basin.
The 9 in. and 12 in. catch basins have a cut-out in the bottom of the boxes. If this is removed, then the outlets that connect to the 9 in. and 12 in. catch basins can be connected.
The size of the pipe connected to the outlets will be the limiting factor when it comes to drainage out of the catch basins. A table with approximate discharge rates for typical drainage pipe is below.
Constant Slope (Gravity Fed)
| Pipe | GPM with 1% Slope | GPM with 2% Slope |
|---|---|---|
| 3 in. Smooth Wall | 63 | 92 |
| 4 in. Smooth Wall | 135 | 196 |
| 6 in. Smooth Wall | 391 | 568 |
| 8 in. Smooth Wall | 833 | 1,211 |
| 10 in. Smooth Wall | 1,498 | 2,178 |
| 12 in. Smooth Wall | 2,420 | 3,518 |
| 3 in. Corrugated | 25 | 37 |
| 4 in. Corrugated | 54 | 78 |
| 6 in. Corrugated | 156 | 227 |
Constant Flow Velocity (2 ft per second, Gravity Fed)
| Pipe | GPM |
|---|---|
| 3 in. Smooth Wall | 44 |
| 4 in. Smooth Wall | 75 |
| 6 in. Smooth Wall | 160 |
| 8 in. Smooth Wall | 280 |
| 10 in. Smooth Wall | 420 |
| 12 in. Smooth Wall | 600 |
| 3 in. Corrugated | 44 |
| 4 in. Corrugated | 75 |
| 6 in. Corrugated | 160 |
9 in., 12 in., 18 in., & 24 in. catch basins have available risers.
The 9 in. and 12 in. risers add 6 in. from the top of the catch basin to the top of the riser. The 18 in. and 24 in. risers add 8 in. from the top of the catch basin to the top of the riser.
The 9 in. riser (916) can be cut to any height and be inserted into the 9 in. catch basin. The 12 in. riser (1216) can also be cut to any height. After cutting the 12 in. riser to the desired height, the strengthening ribs need to be shaved so that the riser will fit into the 12 in. catch basin.
The 18 in. and 24 in. risers can’t be cut.
NDS does not recommend stacking more than 5 risers on top of the catch basins.
Each riser fits snuggly into the catch basin and each additional riser. It is recommended that the soil is backfilled and compacted around each riser prior to stacking the next riser. This will prevent the risers from shifting.
The lips for the 9 in. and 12 in. catch basins and risers are 1-1/8 in.. The base of the risers should not be cut shorter than 1-1/8 in.. Cutting the risers to this length will add 1-1/8 in. to the top of the catch basins. The support ribs for the 12 in. riser will need to be shaved to fit into the 12 in. catch basin.
The 18 in. and 24 in. risers cannot be cut to shorter heights.
The sump area in the bottom of each catch basin is watertight. The connections between the catch basin and the sump boxes, risers, and universal outlets are soil tight, not watertight. Adding a bead of waterproof silicone on each surface being connected will create a watertight connection.
When backfilled with soil, sand, or gravel the catch basins are rated for loads up to 60 psi (pedestrian traffic).
When encased in 4 in. of concrete they are rated for loads up to 175 psi (light vehicular traffic).
When encased in 6 in. of concrete they are rated for loads up to 325 psi (semi-trucks).
When encased in 8 in. of concrete they are rated for loads up to 575 psi (heavy-duty fork lift).
The grate that is used must also have a load rating greater than or equal to the expected load.
At this time, NDS does not manufacture a filter for the catch basins.
See the table below for available grate types and colors:
| Catch Basin | Flat Plastic | Atrium Plastic | Cast Iron | Galvanized Steel | Brass | Magnesium Bronze | ||||
|---|---|---|---|---|---|---|---|---|---|---|
| Black | Green | Gray | Sand | Black | Green | |||||
| 9 inch | ✅ | ✅ | ✅ | ✅ | ✅ | ✅ | ✅ | ✅ | ✅ | |
| 12 inch | ✅ | ✅ | ✅ | ✅ | ✅ | ✅ | ✅ | ✅ | ✅ | ✅ |
| 18 inch | ✅ | ✅ | ✅ | ✅ | ✅ | ✅ | ✅ | |||
| 24 inch | ✅ | ✅ | ✅ | ✅ | ||||||
The top of the Spee-D Basin is made to fit a piece of 6 in. SDR 35 pipe. After placing the Spee-D Basin in the hole, measure from the inside lip of the Spee-D Basin to the surface and cut the 6 in. SDR 35 pipe to length. Slide a 6 in. PVC coupling (part # 6P05) over the end of the pipe and then slide the 6 in. grate onto the coupling.
The 1200NGB catch basin has been designed to allow for the outlet to be at 1 of 3 levels. The side panels (part # 1207) for the 1200NGB are stamped to indicate which tabs need to be removed.
If you want the outlet to be as low as possible, the 2 bottom tabs on the side panel need to be removed. At this position, the center of the outlet is 9-1/16 in. below the top of the catch basin.
If you want the outlet to be centered, the top and bottom tabs need to be removed. At this position, the center of the outlet is 6-15/16 in. below the top of the catch basin.
If you want the outlet to be as high as possible, the top 2 tabs need to be removed. At this position, the center of the outlet is 5-9/16 in. below the top of the catch basin.
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