The "Blue Hole"

The "Blue Hole"

Wednesday, April 6, 2011

So what's the Alternative?

So, what if the Hildebrand drainage project is permanently enjoined (stopped)?  

We believe the City will find even better alternatives for meeting our community's needs.  Where one window closes another opens.  We would suggest for starters:
  • Un-bundle the street and utility projects from the (illegal) drainage project;
  • Fund the desirable add-on projects (street reconstruction, under-grounding of utilities) on schedule using 2007 bond savings, or other city money;
  • Revise the Broadway Corridor - Phase IIIA drainage project to take stormwater down Broadway to the river at Carnahan (as originally intended) or better yet to the river at Tuleta, 0.10 mile further south; and
  • Plan to extend the Catalpa-Pershing drainage channel up to the river at Tuleta as part of the 2012 bond program (something the City has already committed to doing).

We believe the City can design a stormwater system that would drain
 the 100-year flood event off the Broadway-Hildebrand intersection
 according to the original limits of the bond while
not sacrificing the river at its headwaters 
nor risking irreparable harm 
to sensitive historic resources in and between 
Miraflores and Brackenridge Park.  


Take a look at the two drainage project alternatives the city considered (the only two).  Here is the original bond project as approved by the voters:

Note: full title and scope of bond project does not mention Hildebrand.  
Broadway Corridor - Phase IIIA (Carnahan to 150 feet north of Davis Court)


Now look at the redirected Broadway Corridor - Phase IIIA bond project:  
the "Hildebrand alternative."  

NOTE: Yellow lines coming down Broadway south of Hildebrand show how the project drains water from this southeast corner of Broadway-Hildebrand (at Broadway Tower) and back-flows north ( ! ) into the Hildebrand drainage culverts where it eventually dumps into the SAR. The stormwater from north of Hildebrand makes a hard right angle turn, as the City Engineer says, to follow the existing flow pattern.

It does not take an engineer's certificate to see that these are not the same project in scope or intent.

With a modest refinement to the original voter-approved bond, the city could avoid any impact to the Witte property at the existing Carnahan drainage channel by extending the new drainage culverts one-tenth of a mile down to Tuleta at the lower south end of the Witte property. To do so would involve only one landowner, the Witte, aka the City!  

From the river at Tuleta, a long sought pilot channel -- perhaps as a 2012 bond project -- could divert up to 1,500 cubic feet per second of flood water to the Catalpa-Pershing drainage ditch where it would then flow into the big tunnel at Josephine, typically arriving before the flow coming down the meandering main stem of the river through the Park.  This sequences the timing of peak flows entering the tunnel thereby improving the system's overall capacity to carry that 100-year storm event.  Such a holistic approach would not only address the problem of street flooding at the Broadway-Hildebrand intersection in a manner consistent with the voter-approved bond, but also  help remove valuable property and homes from the 100-year floodplain in the River Road neighborhood and along Broadway.

Design of pilot channel and series of ponds connecting the Catalpa-
Pershing drainage channel (at far left) to the river at Tuleta.


You can find descriptions and technical details relating to most of these ideas in the City's (or County's or River Authority's or River Improvement Project's) own engineering studies, reports, and conceptual designs.  The point is there are other, much better options than the hugely destructive one at Hildebrand.  


Doing this step-wise approach towards the holistic solution of stormwater drainage and flood control along Broadway would leave the pending street improvements on Hildebrand without an immediate source of funding.  But please remember that the street improvements were only incidental to the drainage project if the City is to be believed.  Broadway drainage  bonds are after all the current funding source for the now desirable Hildebrand street  improvements (for which there was no 2007 bond project).

The Headwaters Coalition and the Incarnate Word Sisters want to see the street improvements at Broadway and Hildebrand go forward on or near the current schedule, if at all possible.  We drive that intersection every day and know it could use help, but it is not essential  that the street work happens right now.  To get the street improvements now  as part of the city's redirected (possibly illegal) Hildebrand drainage project means sacrificing the river at the top of Brackenridge Park:  at the northern terminus of the current San Antonio River Improvements Project!  


And that is simply not acceptable.  


If the City cannot allocate funds to continue the street improvements on schedule -- and we believe they can* -- we may just have to wait for the 2012 bonds.  


* remember the impressive $47 million in bond savings the City Manager is managing!

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