I am trying to recalculate the HGL of a simple run of pipe after adding 3 more cfs into the system that it wasn't originally designed for. (Original design used wrong C factor in rational formula) I have a known elevation of the HGL and velocity at any given point along the stretch of pipe...
We have a new development needing to connect into an exiting 18" RCP pipe. The Manning's gravity capacity for this pipe at 3.03%, n=0.013 is equal to 18.3 cfs. There is no tail water.
The inflow point of the pipe is a curb inlet. There is the ability to surcharge the pipe, by assuming the...
Can anyone point me in the direction of published charts for estimating sanitary sewage flows? I'm working in Texas and found a good reference under the TCEQ Chapter 317 "Design Criteria For Sewerage Systems". I'd like to compare my findings against a national publication for flow estimations.
I have a project where a municipality requires that a detention basin be able to store the 100-year, 2 hour rainfall event for the site without exceeding the pre-developed discharge rates.
The area in question is relatively small, under 2 acres of parking. I'm not sure if I should be using the...
Here in Texas we have expansive soils, lots of clay. Under normal circumstances only the first foot or two of soil is affected seasonally, drying then re-moistened with the associated movement.
The last 2-3 years have been a record drought, where it's suspected the soil was dried out to a much...
We have a new project in Oklahoma where we hired a local geotech to test the site and make recommendations. For pavement recommendations (rigid) I'm used to geotechs outlining subgrade treatment, pavement strength and thickness, along with RFT spacing and sizing.
Anyone familiar with...
I am doing some preliminary cost estimating for a lift station and force main. I've sized the lift station by estimating daily demand and peaking factors (4) to get a GPD for the lift station.
In sizing the force main I've been looking at velocity based on converting the GPD into Cu.Ft/second...
Can anyone refer me a link to a sanitary sewer study for a small municipality.
I've got a prospective retail development in a somewhat rural community and the City manager is asking for a sewer study to verify capacity. Initially I performed analysis on only the sanitary shed the retail...
I'm trying to estimate the volume of flow into an existing lift station to see if it has available capacity.
The lift station needs to support about 485 single family lots, one elementary school, and 20 acres of commercial (retail, office and restaurant).
For residential lots I've previously...
Was on vacation the other day and driving on the highways I noticed something I'd never seen before.
There are what appear to be longitudinal grind marks in between transverse concrete joints. The grind marks are about 2-inches wide, perhaps 2-feet long and cross the joint. They were spaced...
I have a proposed 10 acre commercial development that will require a lift station and force main. The nearest town gravity main is about a mile away.
However, near the property is an existing 4" force main to the gravity main, which is fed by a town lift station serving a residential...
In your area of practice, does the civil engineer typically prepare the SWPPP reports for construction projects?
I work in the Dallas region, and construction projects that will disturb more than an acre need to get a permit from the TCEQ. That requires a SWPPP and erosion control plan...
I have a site with multiple retaining walls, ranging from 5-15 feet. Guard rails were constructed on top of the walls in many areas.
These guard rails are horizontal tubular steel, (rows of 3), similar to what you might see along a handicap ramp.
The retaining walls are primarily located at...
I've got an access road looping back on itself on a moderately sloped site.
There is a vertical separation between the two roads as they converge from 0 to about 8 feet maximum. I am able to maintain a consistent slope of 1:1.33 (V:H)across this vertical separation. I'm proposing a non...
Has anyone heard of connecting a new sanitary force main into an existing sanitary force main?
I've got a residential development that will need to use a force main and lift station to pump some distance to a treatment plant or gravity main.
There is a closer connection to an existing force...
I have a new project for a school that will build a 2,000 seat arena at an existing campus. The arena will generate 310 Fixture Units, or about 0.25 cfs during peak use.
The sanitary tie in will be a private 4" lateral, currenty serving a maintenance building and baseball concession stand (low...
I've recently come across an issue for one of my projects regarding a SWPPP requirement in Texas. The TPDES permit has a published requirement that any site with more than 10 acres of disturbed land 'should' have temporary sedimentation basin(s).
The guidelines for the basin sizing according...
I am a civil engineer helping to coordinate a project that proposes a multi story building with a basement storage.
There is expected to be groundwater near the bottom of the basement, so sub floor drainage would be prudent. I envision granular material below the slab, with perforated pipe...
Yesterday I took a tour of the new Dallas Cowboy stadium and it is an engineering marvel. Above the field is a mammoth 4 sided scoreboard/screen, the bottom of which is 90 feet off the playing field. (Its length extends from 20 yard line to 20 yard line)
There is debate as to whether that is...
I am designing the subfloor drainage for pier and beam building, with a 6-foot crawlspace. Groundwater is not an issue.
It is a fairly large and geometrically irregular structure, approximately 6.4 acres in area of crawlspace.
The subfloor drainage is only intended to pick up 'emergency'...
