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EagleLandscape
01-08-2009, 07:23 PM
I have a commercial customer that long story short needs to keep this grass area free from excess water. The depth of this bed is only like 8-12". It sits on top of a parking garage, but also shares a wall with the basement offices.

During excessive rain, or when this fountain overflows, this grass area recieves too much water, and ends up flooding the basement offices.

she had a proposal to do an 8" tall oklahoma flag chop wall, as to divert the water away from the grass and onto the sidewalk. i dont have much faith that the wall bordering the grass is going to be an effective-long term barrier for water.

my vote is to install 2-3 seperate french drains and just suck all the water out of this area. It has positive drainage to drain down hill, but then again its only 8"-12" deep.

She had a quote for 85' linear ft of 8" tall wall. I figure 2 tons of chopped flagstone, but I don't think the bidding contractor was planning on pouring a footer... thoughts? what can my customers options be?

mrusk
01-08-2009, 08:51 PM
So in the first pic the water is collecting in that grass area between the side walk and the building? Do you have any pitch to work with?

wurkn with amish
01-08-2009, 09:13 PM
Sounds like they need to fix the roof first if its leaking. the rubber membrane is probably torn somewhere.

Bru75
01-09-2009, 12:09 AM
I think wurkin with amish is right about the roof.
Does the area need to stay grass? Could you take it all out, install a drain and then fill the whole area with clean decorative gravel? That would give you some holding capacity when the drain is overwhelmed. Sounds like the grass area is either saturated or not permeable enough to allow drainage.
Hope this helps.

EagleLandscape
01-09-2009, 08:16 AM
yes, that grass part between the sidewalk and the building is the problem area. from where i shot the picture, it drains downhill to those shrubs in the distance. enough for a french/gravity drain.

someone just tell me that a wall won't solve their problem to barricade the water. i dont think it will, but i want someone to tell me that. (if its true of course).

I'm just thinking alot of drains.

they wont go for decorative rock. that would cost several thousand dollars, and 26 yard of rock. We put in some rock there a few months ago, and we used some black tejas granite. it was like 400 a ton, or something.

oakhillslandscaping
01-09-2009, 09:13 AM
I think a wall would be to ostentatious and wouldnt fit in with all that concrete, drains can work but how would it look? i.e. how many drain covers are gonna be in that little bit of grass? have you thought about other options like taking the grass out and making it a raised planting bed with perenials or a ground cover? that may work with the addition of a few drains hidden at the base of the bed just my thought good to you

Bru75
01-09-2009, 09:19 AM
You are correct, I think, that a wall would be pretty much pointless in solving the water problem.

Dreams To Designs
01-09-2009, 11:39 AM
Unless the wall had a channel drain between it and the sidewalk running the entire length, it would be only partially effective, especially if it were dry stacked, Anyway you look at it, you need to get the excess water out of that area quickly and efficiently, and most likely that will be accomplished using drainage fixtures and pipe. A channel drain between the sidewalk and grass area with an outlet on the low side or better yet, into the existing drainage system would be a simple way to solve this issue.

Kirk

EagleLandscape
01-09-2009, 02:14 PM
unless the wall had a channel drain between it and the sidewalk running the entire length, it would be only partially effective, especially if it were dry stacked, anyway you look at it, you need to get the excess water out of that area quickly and efficiently, and most likely that will be accomplished using drainage fixtures and pipe. A channel drain between the sidewalk and grass area with an outlet on the low side or better yet, into the existing drainage system would be a simple way to solve this issue.

Kirk

bingo!!! Thats the solution!!

Lite4
01-09-2009, 07:02 PM
I was just going to agree with Kirk. I have had the same problem in the past and the channel drains work fabulously and blend right in with the side walk.

wurkn with amish
01-09-2009, 07:47 PM
all your doing is putting a band -aide on the problem.
if they are willing to do that then I guess take their money.

Bru75
01-09-2009, 08:57 PM
The channel drain should be fine.

EagleLandscape
01-10-2009, 10:17 AM
all your doing is putting a band -aide on the problem.
if they are willing to do that then I guess take their money.

I cannot control the overflow of the fountain, or immense water run off due to the neighboring buildings sprinkler system. all of these factors are controlled and caused by the neighboring sky scraper. my customer's building is only like 10 stories.

http://www.cosmicool.com/midcent/archimages/meadows/mbfront.jpg

the buidling int he far back right is the problem maker.

chanel drain will be perfect

Dreams To Designs
01-11-2009, 12:12 PM
For the correct channel drain size and components, contact NDS or ADS, both companies are very good to work with and will have a technical expert that can help you determine what you will need, for free. I work very closely with NDS regularly and with drainage being a huge part of every landscape project, they are a true asset.

http://www.ndspro.com/cms/

Kirk