drainage area bigger, the ToC will be greater and the Intensity will be smaller. The assumption here is a larger area is hard to get a uniformly distributed rainfall at a higher intensity.
water is kind of incompressible and the volume change (increase here) from 200kpa to 100kpa is small. So you can calculate the volume increased according to water phase diagram which is a very very small number I would assume.
Without using 2D modeling, what’s the best way to calculate an existing roadway sheet flow profile (HGL along roadway) under different return period storms? Suppose the roadway has subsurface storm sewer as well as roadside drainage ditches. Thanks.
Your question is too broad. What kind of dual drainage system you want to mode – for example, do you really want to model each inlet opening as a weir/orifice or just a simply manhole without flow restriction? Your budget and time?
Modeling a dual drainage system in EPA SWMM is very time...
They will generate small difference suppose you use same CN, TC, rainfall,...
but I don't see why they did not use HEC-HMS for pre if the purpose is to compare the two conditions.
sand filter/fabric filter or the combination is to retain underlying soil from being washed out and at the same time to allow water release to ground. The filter needs to be designed to meet the grading requirements (FHWA, USACE, or NRCS has such criteria) and sometimes you need multiple layers...
Method 2 seems kind of double dipping the impact and that's why you got a lower discharge. I would go with method 1,and also make sure since you are modeling the depression as reservoir, when you calculate your basin hydrological parameters, don't include any factors from the reservoir.
In HEC-RAS 2D modeling,will water get lost from 2D flow areas? or water will build up against an imaginary wall at 2D area boundaries (similar behavior happen at HEC-RAS 1D cross section limits)?
How do we set up flows from HMS (via HEC-DSS) for use in HEC-RAS? I am talking internal boundary conditions - there are two options in HEC-RAS, namely uniform flow and lateral flow.
If I have subbasin say "A" and the river in HEC-RAS runs through its center. Should I introduce A flow by HMS...
You need to figure out how to model hydrology in SWMM
1. use SWMM hydrology to general hydrograph (It is basically a non linear reservoir routing method);
2. develop hydrograph outside of SWMM and introduce them at nodes as external flows;
Also, you need to understand that SWMM is a dynamic...
thanks for clarifications.
So, to me, all these terms are not strictly defined, one person's select fill could be another one's engineering fill, or structural fill.
1. can anyone explain to me the difference among engineering fill, select fill, structural fill, and general fill?
2. And for a berm of a dry detention pond, what type of fill is appropriate and material type - sand, clay, silt, or in terms of PI?
3. For backfill of a storm sewer pipe under...
if local government review agency allows, it seems it is just easier to model the whole thing in a dynamic model which consists of storm sewer, pond, street (as major a drainage system for spread analysis), inlets (model it as weir and/or orifice).
Any hydraulic design criteria on a relief bridge? like low chord setting, or relief bridge low chord EL. relationship with main channel bridge? Thanks.
