Search results for query: *

One suggestion is for a concrete U-shaped ditch behind the building abutting the hill.

Hi Engr Salah, 1) Is your data recorded for reach 24 hour? 2) Is the rainfall similar to any nearby Cities where IDF curve is available? 3) Are you trying to create a storm hyetograph? 3) Is the hydrograph needed for river basin or small urban catchment? Thanks

If you have not done so already, you can also look into any published standards and order of accuracy requirements like http://www.dot.ca.gov/hq/row/landsurveys/SurveysManual/05_Surveys.pdf Thanks

Yr, a0, a1 1, 0.103903, 0.313687 2, 0.128763, 0.305261 5, 0.177688, 0.291029 10, 0.226557, 0.279501 25, 0.307198, 0.264093 50, 0.379736, 0.253163 100, 0.462293, 0.242978 200, 0.555014, 0.233734 500, 0.694905, 0.222314 1000, 0.807472, 0.215545 DDF Coefficients calculated using PDF from NOAA for...

Hi Bank, http://www.hydrocalc.com/beta/rain_ddf/main.html If NOAA (http://hdsc.nws.noaa.gov/hdsc/pfds/) has the depth duration data for your area, you can follow this hyetograph generator. It basically allows converting depth duration data to IDF coefficients--and then the IDF coefficients to...

PCSWMM maintains a SWMM5 inp file at all times. I think XPSWMM should be able to open that file.

Also, http://www.epa.gov/nrmrl/wswrd/wq/models/swc/ If you download the above EPA National Stormwater Calculator software, it can access the available raingauge data for a given geographic location. Then, you can save that file. It will be in SWMM5 rainfall data in tab separated format like...

You must have realized it already. Assuming additional 3 cfs flowing through the same pipe means you (unknowingly) changed both the HGL and EGL. So you just start again from scratch. Re-calculate both HGL, velocity and EGL. Thanks

Not an exact answer to the original question. But I have put this website together for our particular IDF data for routine storm analysis. http://www.hydrocalc.com/beta/rain_analysis/analyzer.html It can be modified relatively easily for other IDF curve data. Thanks

DrainageR, Most tutorial starts with complexity. To explain SWMM5, I start with the simplest network possible. Two tanks connected with one pipe, and one outfall. Try to run it and then try to understand it, and try to manipulate it. Thanks [TITLE] [OPTIONS] FLOW_UNITS CFS...

EPA SWMM5 can be put to use to perform all that you mentioned and much more. But oen needs to invest time to understand ways things are represented in SWMM5.

As professionals, if we do not voice these concerns, of misuse of procedures and mathematics, who will? Many over zealous and under-educated regulators are out there. They must be challenged in a professional setting.

beej67: ArcGIS spatial analyst watershed delineation tool is available as a Model. see esri script website. Pre or post processing can be automated in the model builder depending upon user's unique requirement. For example: we needed boundaries to follow certain criteria like do not cross a...

Thanks, atook. I was discouraged to try to do this. Best I can think of right now is to first use lisp to attach the dxf data (that I am after) to entity's Xdata. Then I can use VBA to read it.

I need to read dxf code value using VBA - but not using lisp. Say (96. "somedata") is dxf pair for an entity. I want to know if VBA can directly return "somedata"-if I select an entity. With lisp, it is as simple as: (dxf 96 (entget (car (entsel))))

I am not answering the original question, but for others to consider: javascript is an easy simple tool for simple to somewhat complex calculations. it seems to be ignored by engineers (not software engineers, of course) i have implemented some calculations for regular use at...

Use my www.hydrocalc.com (Don't forget to select Normal depth radio button to get depth. Otherwise it calculates flow.)

ken100: No question is silly. Using your data, the max. theoretically possible pond elevation is 227ft - that is if there were no outlets and if all of the 3.5 acre surface was totally impervious. Here is why. Total Vol. from rain possible in 24 hrs = (2/12 ft*3.5 acres*43560) = 25410 cu. ft...

JOhnny: IF the concern is that the MH lid gets blown off by pressure of air or water, a manhole cover with a hinge is available. IF the concern is odor, a diaphragm (a thin light circular metallic disc) is available that is installed directly below the manhole cover. But if the ventilation is...

KatieTX, I haven't used HY-8. Theoretically, an infinitely long 24 inch diameter pipe, if it is steep and the discharge is below the full flow capacity, will flow partially full. It will have supercritical flow. Any tailwater, in such a case, will have no effect on the flow.