Jump to content

Kidd's Hill/Crabtree area development


Recommended Posts

16 hours ago, ctl said:

The creek peaked at 13.46 feet on Saturday afternoon.  At 14 feet it gets into the parking lot. At 18 feet it gets into Macy's. At 22 feet, Creedmoor Road floods. At 23 feet, Glenwood Avenue floods. The all-time record is 27.69 feet in 1973, just after the mall opened and before any of the upstream runoff mitigation projects was in place. In recent years the record is 23.77 feet, Alberto, 2006. 

The watershed of Crabtree Creek upstream from the Mall is not that large. See the picture (which is Wake County only ; some of the watershed extends into Durham County.) Remember, the rain has to fall in the purple area west of the Mall to have an effect here. For example, if Shelley Lake in north Raleigh overflows, it will cause flooding on Crabtree Creek downstream from the Mall. 

With advance notice, mall management was ready this time. They had closed the bottom level of the parking deck and put a watertight cover over the Macy's entrance that faces the creek.

Static 12 WS Map.jpg

And luckily for mall management, the last WRAL map I saw was only about 5.5 inches of rain in that area over 3 days..well within the bank full limits of the stream. 

  • Like 1
Link to post
Share on other sites

  • Replies 234
  • Created
  • Last Reply

Top Posters In This Topic

Top Posters In This Topic

Popular Posts

The creek peaked at 13.46 feet on Saturday afternoon.  At 14 feet it gets into the parking lot. At 18 feet it gets into Macy's. At 22 feet, Creedmoor Road floods. At 23 feet, Glenwood Avenue floods. T

Construction has started on East West Partners new office building by Crabtree.  Took this photo today. http://ewp-nc.com/project/crabtree-terrace/

New office building next to Crabtree Valley Mall attracts first office tenant. https://www.bizjournals.com/triangle/news/2018/08/27/co-working-lease-prompts-start-of-large-office.html Also t

Posted Images

My unscientific calculation has about 100 square miles of watershed draining through Crabtree Valley Mall, 85 of which are upstream of the quarry and 15 downstream.

Highest modern day observed flow rate (from the 2006 flood) is 12,000 cfs whereas the flow rate at 18' is 5,000 cfs. That would be an excess flow rate of 7,000 cfs. If up to 85% of the flow (from upstream of the quarry) could potentially be diverted, that is more than enough to absorb 7,000 cfs. This would fill a 2 billion gallon quarry (my estimate of its capacity) in about 11 hours.

I'm not sure how long the flood lasted in 2006 but the watershed is small enough that I imagine excess runoff from the very outer most reaches of the headwaters will make it down to Crabtree Mall in a matter of hours, if not minutes. This means that a flood would clear away relatively quickly - much less than 11 hours- once the worst of the deluge clears.

There are scores of people and lots of tools to do these calculations the right way, but my back of the envelope math indicates that it would probably work... once the city buys the quarry in 2054 anyway.

As an interesting aside: the bottom of that quarry is over 100 feet below sea level!

Link to post
Share on other sites

I agree, it should work fine for 2006-scale events. And even if it's only partially successful for Fran/Floyd-scale events, it would help. Pumping all that water out of the quarry afterwards will cost some money, but I expect it's cheaper than fixing damage done to public infrastructure by flood water. Perhaps the county could levy a special property tax on those who built or bought in the flood plain of the creek.

In the meantime, the only practical solution is to deepen Lake Lynn, Lake Crabtree, etc. Draining them and taking out the muck is messy, smelly, expensive, ugly, and environmentally injurious... why it hasn't been done already. And in the case of Lake Crabtree, we might be better off leaving the PCB-contaminated banks and bed alone. But those lakes are silting up and don't have the storage capacity that they did when new. 

 

Edited by ctl
Link to post
Share on other sites

Believe it or not the base flood elevation in this area is set to drop 6-8 feet across all off these properties. That is if Wake County ever actually intends to adopt the new maps. The FFE on the new office building that is going up across from Macy's will sit 2 feet above the former FFE elevation of the building it is replacing, which never took on any first floor water in any of the Hurricane events since the 90's. These properties are already developed and impervious, so there is really no reason not to redevelop and modernize them at this point.

  • Like 1
Link to post
Share on other sites
1 hour ago, rucker said:

Believe it or not the base flood elevation in this area is set to drop 6-8 feet across all off these properties. That is if Wake County ever actually intends to adopt the new maps. The FFE on the new office building that is going up across from Macy's will sit 2 feet above the former FFE elevation of the building it is replacing, which never took on any first floor water in any of the Hurricane events since the 90's. These properties are already developed and impervious, so there is really no reason not to redevelop and modernize them at this point.

I have some education in this but no professional experience so perhaps you can answer question. Are flood mitigation devices included in the map elevations or is it just runoff coefficients/impervious/pervious areas and slopes? I would imagine so and they'd get treated like separate basins upstream of there point releases, but never witnessed a model in action. 

Link to post
Share on other sites
  • 2 weeks later...

Another Westin hotel proposed in addition to the 18 story Westin at Crabtree.  This 10 story is proposed at Brier Creek Corporate Center

""Plans filed with city show a 191,000-square-foot building with 228 rooms, to be built on a 4-acre parcel carved out of a larger tract of land just east of the main Brier Creek Town Center.  The Brier Creek location is the second currently making its way through the city’s planning process – another is being planned next to Crabtree Valley Mall and would rise 18 stories.""  Crabtree location would be 252 rooms. 

subscriber article https://www.bizjournals.com/triangle/news/2018/09/27/another-westin-hotel-planned-for-the-triangle.html?ana=e_du_prem&s=article_du&ed=2018-09-27&u=oAaDx%2B74FoP4qOJ%2By4AU6dhJPpc&t=1538078240&j=84075891

 

Edited by KJHburg
  • Like 3
Link to post
Share on other sites

Interesting choice, given that Marriott now owns the former Starwood brands (St. Regis, Luxury Collection, W,  Sheraton, Westin, Le Meridien, Tribute, Design, Four Points, Aloft, and Element). Of those, Westin is a full-service, business-oriented brand for domestic locations. 

  • Like 1
Link to post
Share on other sites

  • 1 year later...
  • 3 weeks later...

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • Recently Browsing   0 members

    No registered users viewing this page.

×
×
  • Create New...

Important Information

By using this site you agree to our Terms of Use and Privacy Policy. We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.