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Showing posts from August, 2012

Singapore NEWater Program

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From Toilet To Tap Paul Rozin argues that we need to overcome our disgust with recycled water. He offers Singapore's NEWater as an example of effective marketing:  Four treatment plants throughout the country take sewage, filter it through several membranes, and expose it to ultraviolet light to make it safe to drink. Now 30 percent of the country’s total water demand is met using reclaimed (i.e., recycled) sewage. The program’s success was due in part to a dedicated communications team that conducted a massive public education campaign, which included a TV documentary. But Singapore also made the decision to release the cleaned-up wastewater into reservoirs, where it got re-treated along with regular tap water. This extra step was hygienically redundant but psychologically vital in helping Singaporeans accept NEWater as a fact of life. The above animation was created by primary school students in Singapore.

God Created the World, But the Dutch Created the Netherland

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God Created the World, But the Dutch Created the Netherlands By   |  Posted Monday, Aug. 27, 2012, at 10:10 AM ET Horace Dediu's presentation on the history of Amsterdam features the amazing land reclamation map above. Utrecht, which is now inland, used to be a port. And Amsterdam is where the ocean used to be. Haarlem is part of the mainland but looks to be located on what was once a barrier island.
It's a commonplace of economics that they're not making any more land, but this is a powerful reminder that once upon a time it was actually pretty common for technologically advanced societies to build more land. Leaving that era behind us is probably a good idea (imagine the environmental impact review!), but that only makes it all the more important to try to use the land we do have wisely.

Indoor Plumbing Is an Amazing Invention

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Indoor Plumbing Is an Amazing Invention By   |  Posted Monday, Aug. 27, 2012, at 3:25 PM ET
A young woman washes her face at a newly built deep water well in 2010
Photo by Roberto Schmidt/AFP/Getty Images. Robert Gordon has a working paper out making some not-particularly-persuasive, super-pessimistic, speculative claims about the future of American economic growth that does include, as an aside, this very persuasive observation about consumer surplus: A thought experiment helps to illustrate the fundamental importance of the inventions of [Industrial Revolution] #2 compared to the subset of [Industrial Revolution] #3 inventions that have occurred since 2002. You are required to make a choice between option A and option B. With option A you are allowed to keep 2002 electronic technology, including your Windows 98 laptop accessing Amazon, and you can keep running water and indoor toilets; but you can’t use anything invented since 2002. Option B is that you get everythin…

Raining Water

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Via http://headlikeanorange.tumblr.com/





How Does Horton Infiltration Work in SWMM 5?

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How Does Horton Infiltration Work in SWMM 5?by dickinsonreThis sketch summarizes what happens in a SWMM 5 Subcatchment for Horton Infiltration during a storm event:
1.The event starts out with the potential infiltration rate at the maximum infiltration rate but 2.Decay starts happening right away and the potential infiltration rate starts decreasing until it reaches the minimum infiltration rate (assuming the storm last long enough), 3.The actual infiltration rate is the minimum of the rainfall rate or the potential infiltration rate, 4.Using the Huff distributions for rainfall the runoff does not start happening until the rainfall rate exceeds the potential infiltration rate in these models 5.The runoff ceases after the rainfall rate becomes less than the current potential infiltration rate later in the storm, 6.The maximum infiltration volume for Horton caps the storm event infiltration at 10 mm in this example, the infiltration will cease when the cumulative infiltration reaches 10 mm. 7.…

SWMM 5 Weir RTC Rules

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Subject:   SWMM 5 Weir RTC Rules

SWMM 5 Weir RTC Rulesby dickinsonreSubject:   SWMM 5 Weir RTC Rules
This example SWMM 5 model closes a weir based on the depth at the upstream node of the Weir every 0.25 feet.  You can see the effect of the RTC rules using a Scatter plot of Weir Flow versus Weir Depth in SWMM 5 (Figure 1).   The Weir flows normally every 0.25 feet but shuts down three times using these rules which set the Weir Setting to 0.0
RULE Weir100 IF Node  WeirNode Depth > 1.75 AND Node WeirNode Depth < 2.0 THEN WEIR WEIR Setting = 0.0 Priority 2
RULE Weir101 IF Node  WeirNode Depth > 2.25 AND Node WeirNode Depth < 2.5 THEN WEIR WEIR Setting = 0.0 Priority 2
RULE Weir102 IF Node  WeirNode Depth > 2.75 AND Node WeirNode Depth < 3.0 THEN WEIR WEIR Setting = 0.0 Priority 2
RULE Weir103 IF Node  WeirNode Depth > 3.25 AND Node WeirNode Depth < 3.5 THEN WEIR WEIR Setting = 0.0 Priority 2
RULE Weir104 IF Node  WeirNode Depth > 3.75 AND Node WeirNode Depth < 4.0 THEN WEIR WEIR Sett…

Benefits of Urban Trees

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Via   http://switchboard.nrdc.org/blogs/kbenfield/what_trees_mean_to_communities.html

If you’re interested in the subject of the community benefits of trees, you can get additional information from the websites of the National Arbor Day Foundation and theUS Forest Service.  Among the tidbits I learned on one or the other of those two sites are these: The net cooling effect of a young, healthy tree is equivalent to ten room-size air conditioners operating 20 hours a day. If you plant a tree today on the west side of your home, in 5 years your energy bills should be 3 percent less. In 15 years the savings will be nearly 12 percent. One acre of forest absorbs six tons of carbon dioxide and puts out four tons of oxygen.  A number of studies have shown that real estate agents and home buyers assign between 10 and 23 percent of the value of a residence to the trees on the property. Surgery patients who could see a grove of deciduous trees recuperated faster and required less pain-killing m…

Fifty Years of Watershed Modeling – Past, Present and Future

Fifty Years of Watershed Modeling – Past, Present and Future September 24-26, 2012
Boulder, Colorado
On behalf of Engineering Conferences International and the conference chairs, Anthony S. Donigian, Jr. (AQUA TERRA Consultants), andRichard Field (US Environmental Protection Agency/ORD [retired], Michael J. Baker Jr., Inc.), it is my pleasure to extend this invitation to you to participate in Fifty Years of Watershed Modeling – Past, Present and Future to be held September 24-26, 2012 at NCAR (National Center for Atmospheric Research – Center Green Campus) in Boulder, Colorado. Continuous Simulation using SWMM 5 LID and Groundwater Features in a Linked 1D/2D Network using InfoSWMM 2D for a 50 Year Period
has been accepted for Poster Presentation at the forthcoming conference Fifty Years of Watershed Modeling: Past, Present and Future to be held September 24-26, 2012 at National Center for Atmospheric Research (NCAR – Center Green Campus) in Boulder, Colorado.

Huff Distribution SWMM 5 Model

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A SWMM 5 Model made from the Art of Jack Yerka

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Subject:   A SWMM 5 Model made from the Art of Jack Yerka

A SWMM 5 Model made from the Art of Jack Yerkaby dickinsonre Subject:   A SWMM 5 Model made from the Art of Jack Yerka
The attached example SWMM 5 model has small rectangular conduits with a constant inflow based on a background image from Jack Yerka.
via Blogger http://www.swmm5.net/2013/08/a-swmm-5-model-made-from-art-of-jack.htm

How to use the Flow Splitter in InfoSewer for Dendritic Networks

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Subject:  How to use the Flow Splitter in InfoSewer for Dendritic Networks

How to use the Flow Splitter in InfoSewer for Dendritic Networksby dickinsonreSubject:  How to use the Flow Splitter in InfoSewer for Dendritic Networks
InfoSewer, which is an extension in Arc Map, does need to have flow splits defined where gravity mains merge together to determine the amount of flow in each of the downstream conduits (Figure 1).   The options for the flow splitterin each of the downstream links are: 1.       Automatic Allocation 2.       Fixed Flow Percentage 3.       Variable Flow Percentage and 4.       Inflow-Outflow Curve At an outfall where the invert of the outfall pipe is raised compared to the inverts of the incoming and outgoing pipes a flow split of Variable Flow Percentage or Inflow/Outflow curve may work better (Figure 2). 
Figure 1. Options for Performing a Flow Split in InfoSewer

Figure 2.  The Effect of the flow split can be used to model complex situations in a dendritic model with out…

How to Export all of your Data to a Shapefile Using InfoSWMM

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Subject:  How to Export all of your Data to a Shapefile Using InfoSWMM

How to Export all of your Data to a Shapefile Using InfoSWMMby dickinsonreSubject:  How to Export all of your Data to a Shapefile Using InfoSWMM
You can do this easily by using three steps which are shown in Figure 1, Figure 2 and Figure 3.
Figure 1.  Export Manager Tool
Figure 2.  Link and Node Export Options Figure 3. Parameter options for Export to the Shapefile
via Blogger http://www.swmm5.net/2013/08/how-to-export-all-of-your-data-to.html

Rules for NRSCS Unit Hydrographs in InfoSWMM

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Subject:Rules for NRSCS Unit Hydrographs in InfoSWMM

Rules for NRSCS Unit Hydrographs in InfoSWMM and H2OMap SWMMby dickinsonreSubject:  Rules for NRSCS Unit Hydrographs in InfoSWMM and H2OMap SWMM
Rules or Guidelines for NRSCS Unit Hydrographs if used as the Hydrology Option in InfoSWMM and H2OMAP SWMM: 1.       The Unit Hydrograph CN comes from the Subcatchment Table and the NRCS_CN Column 2.      Time of Concentration is from the TC column in the Subcatchment Table 3.      The Infiltration Model should be from the CN infiltration Model Column in the Subcatchment Database Table 4.      The CN in the Soil Database Table should be the same as the CN in the Subcatchment Database Table 5.      If the Depression Storage is zero in the Subcatchment Database Table then the Initial Abstraction in inches will be calculated as 0.2*(1000/CN-10) internally in the engine 6.      Initial Abstraction or IA in US Units =  0.2*(1000/CN-10) in American Units

via Blogger http://www.swmm5.net/2013/08/rules-fo…