The engineering team at Southeast Culvert has designed hundreds of underground detention systems. We partner with civil engineering design firms every day to provide them with resources and experienced guidance according to industry best practices. Our goal is to ensure that your storm drain systems are extremely cost effective, functional, and meet the standards of the municipality reviewing the project.

• Detention Forms Pdf
• Detention For Macular

We regularly receive questions from design engineers about how best to design an underground detention system. A few of the more common questions are listed below.

• The Montgomery County Mac Sim Butler Detention Facility is located in Montgomery, Alabama. The Montgomery County Sheriff’s Department operates and manages the Montgomery County Mac Sim Butler Detention Facility. This facility is also composed of an inmate work center.
• Mac Sim Butler Detention Facility P.O. Box 4599 Montgomery, AL. All mail sent to an inmate at the Montgomery County Detention Facility must include the sender's name and mailing address in the top left corner of the envelope or postcard.

• Should I use pipe, chambers, or another product?
• If I use metal pipe, what diameter and gauge do you recommend?
• How much cover will the underground detention need?

In this guide, we will answer these questions as well as addressing other important criteria in underground detention design.

Everybody had to bring their school macs and gymshoes to Miss Mulcahy's detentions. It was part of her 'No Nonsense' methods. For other teachers they would take a textbook and some paper and work for an hour in a classroom. For Miss Mulcahy it was a mac and plimsolls, and three hours would be spent in the gym.

As always, if you need some design guidance for an underground detention, water quality treatment device, or retention/infiltration system, let us know.

We usually return proposal requests within a day.

Step 1: How much depth do you have to work with?

The allowable vertical space for your underground detention system is one of the most important considerations for what product will work in the application. You have to ensure that the system will have an appropriate cover height to function structurally.

If you have a rough grading plan and your detention outlet pipe elevation, you can calculate the maximum depth (finished elevation to invert out) at the outlet location. Then you will check the edges of the detention’s allowable footprint to see if the finished grade increases or decreases significantly.

Use the shallowest depth you find as your initial allowable vertical space. You can probably manipulate the detention system’s shape and footprint later to increase that vertical space, but this depth is a good starting point for your design.

Step 2: What underground detention product will work in this space?

Every detention product has a minimum allowable cover to allow vehicular traffic loading on the finished system as well as construction loading guidelines. The construction loading minimum cover will always be more than the minimum allowable cover for traffic loading.

Start off your design assuming a minimum cover of 3’ over the detention system. That minimum cover will allow some medium construction loads on both pipe and chambers systems. This guideline does not cover all construction loads and you will need to double check the requirements of the product you specify against the equipment required during construction, but it is a good place to start.

Subtract 3’ from the vertical depth you came up with in step 1. That depth is the allowable vertical dimension of the detention system.

*Note: If the allowable detention footprint and depth based on these guidelines does not allow you to provide the required volume, then you can reduce the cover over the system. That will allow you to expand the system footprint and increase the size of the pipe or chamber system you are using. The minimum cover for either product is in the range of 12-24” to the bottom of flexible pavement or to the top of rigid pavement.

Designing the system closer to the minimum cover requirements will necessitate more coordination with the contractor to make sure that the construction loading requirements are maintained through construction.

Step 3: Choose the most cost effective detention product

Now that you have the maximum vertical dimension of your detention product, you can look at the different available options and do some value engineering.
Generally, the least expensive detention system product on the market is corrugated steel pipe. Designing with the product is fairly easy because the minimum and maximum covers on the product allow you a wider range of design than almost any product.

For instance, the minimum allowable cover on 72” diameter steel pipe for H-20 highway loading is 12” to the bottom of flexible pavement and the maximum cover is 52’. No other product has that range of cover heights.

Corrugated steel pipe is available in a wide range of diameters from 12” to 144”, so you can fine tune your design to maximize your storage volume in the smallest footprint.

For corrugated steel pipe detention systems, choosing the largest diameter allowable leads to a cheaper price for the installed system. The reason for this characteristic of the product is that the amount of steel in the pipe increases according to the perimeter of the pipe (pi)*Diameter while the volume stored in the pipe increases according to the cross sectional area of the pipe (pi)* (Diameter/2)².

For example, the weight of 48” diameter 16 gauge corrugated steel pipe is 38.6 lbs/ft and the cross sectional area is about 12.5 sqft. The weight of 84” 14 gauge corrugated steel pipe is 82.2 lbs and the cross sectional area is about 38.5 sqft. The amount of steel in 48” diameter pipe is about 3 lbs/sqft while the amount of steel in 84” pipe is about 2.15 lbs/sqft.

There would be approximately 30% less steel required per cubic foot of storage for an 84” diameter steel pipe detention system compared to a 48” diameter system. The system footprint would also be smaller.

If the allowable depth does not allow large diameter steel pipe, then you could look at getting budget pricing on a CSP system compared to a chamber product style system.

The general rule for when the cost of a chamber system is competitive with a metal pipe underground system is when the allowable pipe diameter is 54” (4.5’) or less. If your project only has room for a system around this size, then you should get a budget proposal for a metal pipe detention system and a chamber system and compare the costs and system footprints. It is important to consider the amount of stone required for both systems in addition to the material cost.

Want help with designing an underground detention system?

Ask our engineering team for help

Should the corrugated steel pipe detention be perforated or solid?

Designing corrugated steel pipe detentions fully perforated and surrounded in a stone envelope has become very common since municipalities have begun requiring some level of retention and infiltration of storm water on new projects.

Perforating the detention system has several design benefits:

1. The system size is significantly reduced
2. The system is backfilled in stone, which speeds up the installation of the detention
3. The new Georgia Stormwater manual gives full water quality treatment credit if you can show the first 1” of rain being retained and infiltrated.
4. A perforated steel pipe detention typically requires significantly less stone than a comparable chamber system.

What is the least expensive diameter of corrugated steel pipe for a detention system?

As a general rule, the larger diameter you use for an underground detention system, the cheaper it becomes per cubic foot of storage. There are some diameters that are cheaper than others because they are the largest diameter before the pipe has to be made with a heavier gauge of steel.

The least expensive per cubic foot pipe diameters are: 60”, 84”, 108”, and 144”.

Those sizes are based on the industry standard gauging guidelines, but some municipalities have heavy gauge requirements. If you have a question about a system you are designing, you can contact our engineering team. We can tell you the best practices for the specific municipality reviewing your project.

As always, if you want to send your project to our engineering team then we will put together a detention proposal that includes stage storage tables, a layout detail, and budget pricing for the system.

We typically return a proposal within a day of getting a request.

Additional Tips

Use bulkheads in lieu of manifolds

Metal pipe detention systems consist of individual runs of pipe joined together with a manifold on the end. The typical configuration for a detention has both ends of the system joined into a manifold, but we recommend leaving the upstream end of the system un-joined and putting bulkheads on the pipe.

The fabricated tees on a manifold a significantly more expensive than bulkhead caps, so using bulkheads reduces the system cost. It also reduces the number of band connections and speeds up the installation of the system.

Use a smaller outlet pipe

One mistake we see a lot on underground detention designs is to tie the detention pipe itself directly into the outlet control structure on a system. For larger diameter pipe detentions, that configuration leads to large precast OCS structures. Reducing the outlet pipe to 36” pipe or something similar can reduce the cost of the OCS structure by thousands of dollars.

Design the OCS weir plate inside the detention pipe

A custom weir plate can be fabricated inside the pipe to eliminate the OCS structure. Designing the system with an internal weir plate can reduce the overall cost of detention, especially for large diameter systems where the required OCS box would be expensive.

Detention is a side-scrolling point-and-click horror game set in 1960s Taiwan under martial law. Students Wei Chung Ting and Fang Ray Shin find themselves trapped in their school during a typhoon destroyed the bridge leading home. But they discover that their once familiar school is falling into darkness, as evil spirits now roam the halls. The students, trapped and vulnerable, must explore the campus to find objects and solve puzzles, while piecing together the story of how this horror came upon their school.

• 2Official description
• 5Reception

Synopsis[edit | edit source]

Set in 1960s Taiwan during the White Terror period, the protagonists, Wei and Ray, are trapped in their remote school during a terrible storm. The school has changed in disturbing ways, haunted by evil creatures and spirits known as the lingered. As the characters explore their environment, sinister secrets are revealed about the dark past of the school and the characters themselves.

Official description[edit | edit source]

Greenwood high school, located in a remote mountainous area, two students found themselves trapped and vulnerable. The place they once knew has changed in unsettling ways, haunted by evil creatures. To escape, they must explore the mysterious campus filled with ominous objects and puzzles. How will they survive in this ever threatening environment? Could they return to safety in one piece?

Set in a fictitious world in the 1960s Taiwan under martial law, Detention, the story-driven atmospheric horror incorporated East Asian elements rarely used in games. Taoism, Buddhism, Chinese mythology, the game draws on local Taiwanese cultural references to tell an unique and terrifying story.

Gameplay[edit | edit source]

In this 2D atmospheric horror side-scroller, players navigate the main characters in a classic point and click fashion to explore a high school where evil encroaches. While hiding from the rampaging monsters, you are to find items to interact with in the otherworldly rooms. And as more mysteries unveiled, the dark past of a cursed school will finally surface.

Features[edit | edit source]

• 2D atmospheric horror with spine-chilling atmosphere.
• Immersive gameplay and puzzle solving experience
• Unique Taiwanese/Eastern cultural references.
• Original sound tracks, fusing Electronic, Lo-Fi, and Rock with traditional Asian instruments.
• Unique and appealing graphics.
• Multiple language support. (Including English, Chinese)
• Mac, Windows and Linux support

Plot[edit | edit source]

Wei falls asleep in class as his instructor, Miss Yin, is mysteriously called from the room and questioned about a book list. He later awakens to find the school abandoned due to an incoming typhoon. After exploring the area he finds another student, Ray, asleep in the auditorium. The storm prevents their departure as they find the bridge to their village has been washed away by a rising river of blood, so they return back to school to wait out the storm. As Wei departs to find a telephone, the game transitions to Ray as the primary character. Ray awakens in the auditorium once more to a dark and sinister version of the school where Wei is dead and hanged from the ceiling. Ray must wander the school, solve puzzles, avoid malevolent spirits, and find clues to uncover the story behind the school.

Ray was a bright and talented student and the only child of couple whose marriage had soured, causing Ray to neglect her studies. She visits with the school counselor, Mr. Chang to help with her depression and the two fall in love and begin a secret relationship. Unknown to Ray, Chang and Yin have been smuggling banned books for an illegal book club where Wei is a member. Yin confronts Chang about his relationship with Ray and reminds him that it could endanger the club. Ray overhears the conversation and misinterprets it as Yin trying to begin a relationship with Chang. Ray then convinces Wei to give her the list of books for the club, and hands the list over to Instructor Bai, a military officer posted to the school by the government. Yin escapes and leaves the country. Wei and his classmates attempt to burn the books, but are caught and imprisoned. Chang is implicated in the crime and executed. Instructor Bai gives Ray an award for turning in her friends, but she is bullied by her classmates for doing so and she eventually kills herself from guilt. The player is revealed to be playing as Ray's soul, trapped in her memories and unable to accept her guilt.

At this point, the player must make a choice to accept Ray's guilt, or deny her sins. If the player denies guilt, Wei, Chang, and Yin will appear to tell her the cycle will not end. Ray will then enter the auditorium once more and receive a noose as she walks on the stage. As she prepares to hang herself, the auditorium will fade back to reality where the school is abandoned and vandalized.

If Ray accepts her guilt, she will find a paper airplane with a message of love from Chang. As this happens, she sees the moment before Chang is arrested and he tells Ray that people should live freely without fear of oppression. The scene then shifts to Wei, who is an old man now. It is revealed that he was pardoned after the White Terror and Yin spent the rest of her life speaking out against the country's oppression. The game ends with Wei and Ray's ghost sitting together in his old classroom.

Characters[edit | edit source]

• Wei Chung Ting - Wei is a junior at Greenwood High School. He and Ray are friends and he looks up to her. He is apart of an illegal book club and is later caught after Ray reveals his book list to Instructor Bai. He is imprisoned until the White Terror ends.
• Fang Ray Shin - Ray is a senior at Greenwood High School. She comes from a broken home and seeks counseling and a relationship from Mr. Chang. She reports Miss Yin's illegal activities in the hopes of getting her fired, which results in the execution of Chang and the imprisonment of Wei. She is the main protagonist of the game.
• Chang Ming Hui - The counselor at Greenwood High School. He helps Ray cope with her parent's unstable marriage and begins a relationship with her. He is also smuggling in illegal books for an underground book club. After Ray attempts to get Miss Yin fired, he is implicated in the crime and executed.
• Yin Tsui Han - A teacher at Greenwood High School. She runs the underground book club and is fearful that Chang's relationship with Ray will endanger the club. After Ray turns her in, she flees the country and spends the rest of her life speaking out against oppression.
• Bai Guo Fong - A military officer posted to the school by the government. He is extremely strict, encourages students to turn each other in, and is always looking for wrongdoings.

Spiritual References[edit | edit source]

Throughout the game Ray encounters the lingered; malevolent ghosts from East Asian religion and mythology.

• The Lingered - These are female ghosts that resemble Ray. If you don't hold you breath as you pass them, they attack.
• The Lantern Specter - Giant ghosts that carry a lantern and patrol the hallways. You must turn your back to them and hold your breath when they lower their heads to check on you. If you do not, they strangle you.
• Hei Bai Wu Chang - Two deities in eastern religion in charge of escorting the spirits of the dead to the Underworld. They appear on the doors in the basement of the school. When the doors are opened, Ray is transported to a different world.

Reception[edit | edit source]

Critical Reception[edit | edit source]

Detention Forms Pdf

Detention received positive critical reviews, with praise given to the tense and nightmarish atmosphere as well as the historical significance of the plot. Praise was given to the eerie soundtrack that heightened tension and fear. Aggregating review website GameRankings and Metacritic gave the game 83% based on a total of 22 reviews. Rely On Horror gave the game a 9 out of 10, saying that “every facet of Detention moves in one harmonious lockstep towards an unavoidable tragedy, drowning out the world around you.” Detention also topped the games ranking on Steam in Taiwan and reached 3rd in Steam ranking globally within 3 days of its release.

Awards[edit | edit source]

The game received the 'Award for Best Design' from Taipei Game Show in 2017. Detention has also received nominations for Best Narration from BIG Festival, Best Game Award from IndiePlay China, and Best Audio from IndiePlay China.

Detention For Macular