Sanitary Sewer Study 1

[GoldDredger]

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 property is on (about a hundred acres to a lift station, mixed use, existing/proposed, then through a force main to treatment plant).

The town has no master sewer plan. However the manager is now wanting capacity of the treatment plant analyzed, which includes multiple sewer sheds for existing a future uses.

Wondering if I should try to take on this study or sub it out to some civil guys who've done these before.

 

[bimr]

Here are some links to typical reports. One would think that the community has already had some studies prepared in the past because the studies would have been required by the regulating agencies if the community had desired to increase capacity or to address previous effluent violations.

http://www.google.com/url?sa=t&rct=...rce=web&cd=10&sqi=2&ved=0CG8QFjAJ&url=http://

http://www.mi-wea.org/docs/Eval%20o...24GYBA&usg=AFQjCNGtv4RVoSdU7kz2ErQ5M9QRfDlCdg

http://www.google.com/url?sa=t&rct=...urce=web&cd=4&sqi=2&ved=0CEUQFjAD&url=http://

http://www.coanovuspublic.com/Attac...lICoCA&usg=AFQjCNFrrWDx3XMADuLWWDl50vU7lAB9dg

http://city.fortbragg.com/pdf/Wastewater_Treatment_Facility_Study_w_Appendices.pdf

 

[fel3]

It sounds like you may not have the requisite experience to handle this study. For example, from your comments, is appears that you have some experience modeling sewer collection systems, but no experience evaluating wastewater treatment plants and no experience preparing master plans. This is not a criticism, but it is a big red flag. (For example, I have lots of experience modeling sewer systems and some experience preparing master plans--mostly water, a little sewer, and a little storm drainage--but ZERO experience evaluating wastewater treatment plants). Your best choice may be to partner with someone who can fill the gaps in your experience.

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"Is it the only lesson of history that mankind is unteachable?"
--Winston S. Churchill

 

[beej67]

I've never been asked to do an analysis of a wastewater treatment plant simply to do a commercial development. Are you sure that's within your scope? Normally the plant operating entity would be on the hook for something like that.

Hydrology, Drainage Analysis, Flood Studies, and Complex Stormwater Litigation for Atlanta and the South East -

http://www.campbellcivil.com

 

[GoldDredger]

Thank you for the responses. The treatment plant capacity doesn't need to be part of the study, the treatment plant operator (not the City) is responsible for that.

The City manager (new) is trying to figure out what is going on with their sewer system. The record keeping was pretty shoddy over the years, and no-one is 100% sure what is going on with it.

Thanks again.

 

[fel3]

Shoddy record keeping would make this all kinds of fun.

You may want to assume the records that do exist aren't any good and start with a clean sheet of paper, so to speak. You could recommend metering some strategic manholes to get real-time records of what the flows actually are. You should do both dry-weather and wet-weather metering. In addition, it would be worthwhile to compare these flows with similar near-by communities just to make sure you're in the right ballpark.

BTW, I've run across bad records many times before. The most perplexing was at a state prison I was doing some work at: site design for a new building and then the state added a utility study. The facilities operations staff had kept years worth of meticulous hand-written records of daily natural gas usage, even listing the time they read the three master meters to the nearest 5 minutes. Unfortunately, sometimes the meter reading they recorded was LESS than the day before and sometimes they obviously recorded one meter reading on the form for one of the other meters. Fortunately, I was able to resolve most of these hand typos with a little ingenuity. The biggest problem was that their recorded usage was off by a factor of about 2.5 from the monthly totals recorded by the gas utility company (I can't remember if it was ~2.5x or ~1/2.5x). In addition, the predicted gas usage based on other similar facilities with in the state's prison system was about half-way between the two extremes. On the other hand, the daily records (once I straightened out most of the glitches) clearly showed a reasonable pattern, with lower gas usage on the weekends and holidays when the laundry and shops weren't being used. This was still not resolved with I left the company, so we were never able to complete our model of the gas system.

We were also unable to model the sewer and storm drainage systems as per our contract amendment because the state couldn't find any records of the pipe sizes and inverts and they weren't willing to pay us to survey each manhole (it's a real pain inside a prison). The only utilies for which we were able to complete our evaluations were water distribution and electrical distribution.

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"Is it the only lesson of history that mankind is unteachable?"
--Winston S. Churchill

 

[mbcengineer]

Start off with your Health Department Engineering Division records and check into the DEQ for your state for the NPDES permiting records, especially DMR's and NPDES Permit application information. From there, perform a limited opinion on the critical links for existing capacity and contributing capacity from your development which should get you in the ball game.