News / In Depth / Perspective

Caltrans I-710 EIR Belittles While Corps Of Engineers Questions Effects Of Multiple Obstructions For Proposed Freeway "Improvements" In L.A. River Channel


(July 13, 2012, text updated 4:45 p.m.) -- Savvy residents know that "Environmental Impact Reports" (EIRs) frequently try to downplay a proposed project's significant negative impacts. No one is surprised when an EIR for a manure factory claims it won't create significant odors because they don't exceed government standards and the company will provide residents with perfume.

But the I-710 EIR/EIS, released June 29 by Caltrans with the L.A. County Metropolitan Transportation Authority (Metro), proposing up to 14 lanes with a 4-lane "freight corridor," includes aspects that we believe require serious attention.

We sound the alarm here without being alarmist. The project planners propose putting encroachments in the L.A. river channel to widen bridges and relocate DWP power pylons to accommodate a four lane "freight corridor" (truck lanes). The Corps of Engineers has voiced concerns that this may reduce the flood conveyance capacity of the flood control channel, which the Corps says can currently handle a "100-year" (0.01 annual chance) flood and, the Corps says, provides a 133 year (0.0133 annual risk) level of present.

The potential effects of the alternatives as presented in the 1-710 Corridor Study, which include a four-lane freight corridor and other project features that parallel and cross the Los Angeles River and Compton Creek, are of major concern to us... We will need further detailed analysis to properly evaluate whether the proposed alteration or modification to the Federal project can or should be permitted. Without having additional analysis, we note that the relocation of the ten DWP transmission towers and the reconfiguration of the bridge crossings, as proposed, could change the hydraulic functioning of the Los Angeles River channel system, and could have a detrimental impact to the flood conveyance capacity of the Federal project.

...Future modifications to restore or upgrade the capacity of the river could be limited or prevented by the transmission tower relocations and other channel modifications proposed by your project. If your proposed project were constructed, it would limit the potential for future modifications and improvements to the Los Angeles River in the area of your improvements, and this factor weighs heavily in our evaluation. [Source: April 26, 2012 letter from Corps of Engineers to Metro, link to full text below].

Caltrans' draft EIR acknowledges the encroachments but belittles their impacts (bracketed material by us):

...[T]ransverse encroachments would occur at 28 Los Angeles River locations, four Compton Creek locations, and one Rio Hondo location under Alternatives 6A/B/C [three versions of the 14 lane proposal]. At these locations, the encroachments would result from construction of new columns or piers and extension of existing piers. There would be approximately 24,600 square feet of new structure placed within the floodplain. In addition, localized channel modifications would be required to maintain the existing channel hydraulic capacity. A total of 53 acres of property acquisition and/or easements would be required from flood control areas...

...[One cited example among many] Alternatives 6A/B/C [14 lane proposals] would require relocation of the DWP towers to within the Los Angeles River channel. However, the water surface elevation and capacity of the Los Angeles River during a 100-year storm event would be comparable to the existing condition. Because the new piers would mimic the existing pier configurations upstream and downstream, there would be are no substantial effects to the water surface elevation, velocity of flood flows, sedimentation, or scour in the vicinity of the new piers. Because there are no substantial effects at the location of the modification, there are no substantial effects to downstream locations. Final design of channel modifications and associated hydraulic analysis would require USACE [US Army Corps of Engineers] approval. For the same reasons discussed above under Alternative 5A, Alternatives 6A/B/C do not constitute a significant floodplain encroachment as defined in 23 CFR 650.105(q)...

SUMMARY OF FLOODPLAIN IMPACTS. ...According to the Los Angeles River Impact Report (November 2011) [see text below on this], Alternatives 5A [10 lanes without truck lanes] and 6A/B/C [includes 4 truck lanes] would not change the capacity of the Los Angeles River, Compton Creek, and the Rio Hondo Channel to carry water or result in a measurable impact to the 100-year floodplain elevation. The proposed encroachments would not result in any adverse impacts on the natural and beneficial floodplain values, would not result in a substantial change in flood risk or damage, and would not have substantial potential to cause interruption or termination of emergency services or emergency routes. Therefore, Alternatives 5A and 6A/B/C do not constitute a significant floodplain encroachment as defined in 23 CFR 650.105(q).

After learning about these plans, the U.S. Army Corps of Engineers sent a sternly worded letter to Metro on the matter. The Corps' April 2012 letter is in the EIR/EIS appendix and speaks for itself. To read it in full, click here.

Metro responded by saying its "intent" is "to ensure that the flood conveyance of the L.A. River is preserved" with its "goal" to "provide the necessary analysis to allow the Corps and the Los Angeles County Flood Control District to assess the feasibility of the proposed channel modifications before the completion of the environmental phase of the project." It then announced that -- apparently regardless of the impacts -- it plans to seek a permit to allow it to put the truck lanes in the federally designated floodway by calling this the "only practicable alternative finding." Metro's response is also in the EIR/EIS appendix. To read it in full, click here.

Problematic aspects of Caltrans' proposal stem in part from the inclusion of a four-lane freight corridor (truck lanes) (Alternatives 6A, 6B and 6C). The truck lanes were initially proposed to run above the center of the freeway, as they do along part of the Harbor (110) freeway in Los Angeles, but the draft EIR says this was ruled out early in the process when it met with objections from residents who opposed "double-decking" the freeway.

Project planners have now proposed to relocate DWP towers that are currently alongside the 710 and L.A. river to accommodate the truck lanes. This would include using include piers, footings -- and in some cases putting some towers on top of the levees.

"The Corps is not in favor of any modification or alteration that would adversely impact the hydraulic capacity of these flood control features or otherwise impact the authorized function of the LACDA Projectm," its April 2012 letter informed Metro. "Specifically, we recommend that you closely re-evaluate the impacts of the ten transmission towers' impingement on the existing LA River channel section, as well as perform the necessary detailed analysis to adequately determine the hydraulic impacts caused by the proposed bridge widenings and additions, and communicate your findings to the Corps prior to moving forward with your recommended alternatives"

The public's objections to "double-decking" came before these flood conveyance issues were raised.

Our major concern is that Caltrans/Metro -- which don't decide flood conveyance issues -- and the Corps of Engineers -- which does -- appear to be on a collision course at a time when the project's significant impacts are being presented to the public for comment.

As best we can tell at present, the public and their representatives currently can't be certain if the project as currently proposed (especially in its 14 lane form with the 4-lane freight corridor) might trigger a costly bureaucratic scenario. That would take place if the Corps were ultimately unpersuaded by Metro's data and concludes that the project's "improvements" and encroachments impede the capacity of the L.A. river system to handle a "100 year" (0.01 annual chance) flood event.

If that were to happen, FEMA could begin its own process of imposing federally-mandated flood insurance on a potentially large number of family homeowners and commercial property owners in parts of Long Beach and southeast L.A. County and saddle their properties with "flood zone" building restrictions.

The cost of mandatory flood insurance in areas with less than 100 year flood protection depends on multiple factors specific to one's home and loan; we roughly estimate (based on experiences of homeowners elsewhere) that it can cost roughly $500-$1,000 each year. If FEMA were to impose it, the mandate would apply to residential and commercial properties that carry mortgages/loans from federally backed lenders in areas that the Corps and FEMA may ultimately decide no longer receives"100 year" flood protection because of "improvements" by Caltrans/Metro that would affect the conveyance capacity of the flood control channel. .

FEMA's flood zone building restrictions require new construction and "substantial improvements" to existing structures in the impacted areas to be built above the "base flood level" by using stilts or elevated pads. Electrical and heating systems must also be designed and installed in ways that prevent potential exposure to flood waters.

What impacts would such actions have on economic development in affected areas of LB and southeast L.A. County? What areas might be affected? The Caltrans draft EIR/EIS says its hydraulic analysis indicates flood capacity won't be significantly impaired, but it leaves the extent of the area potentially affected to be determined by the Corps and FEMA after Caltrans and Metro finish what they call their "final design." This would almost certainly be after the draft EIR/EIS public comment period ends.

The draft EIR says "No revisions to the FEMA FIRM maps (Letter of Map Revision [LOMR]) are anticipated." For this it cites a "Los Angeles River Impact Report (November 2011)" that it says "assesses the risk of the floodplain impacts." When we read that Report (in EIR's "Technical Studies" section, Volume 1, click here). It includes graphs showing the results of a hydraulic study indicating little change in projected available "freeboard" (area within the flood channel below the levee top that isn't occupied by water) before and after the proposed truck lanes.

The Corps of Engineers has not accepted that conclusion and is seeking additional data. This is a major unresolved issue with potentially significant impacts.

Caltrans and Metro propose to leave these significant local impacts to be determined after the draft EIR/EIS is done:

Final reports will be prepared during final design to demonstrate that the design of the proposed project provides acceptable flood protection. The change in floodplain elevations would be evaluated based on final design plans of the bridges and other structures where they encroach on the 100-year floodplain. The modeling results would be included in the application for a CLOMR [FEMA Conditional Letter of Map Revision] and LOMR [FEMA Letter of Map Revision], if required, which would be processed through the Los Angeles County Flood Control District and FEMA...

...During final project design, and prior to the issuance of any grading permits, the California Department of Transportation (Caltrans) shall process a Conditional Letter of Map Revision and a Letter of Map Revision, if required, for the floodplain and floodway encroachments through the Los Angeles County Flood Control District and Federal Emergency Management Agency (FEMA). This shall include submittal of final detailed applications, certification forms, hydraulic analyses (i.e., Final Los Angeles River Impact Report, including a Location Hydraulic Study), and fee payment to FEMA to obtain a Conditional Letter of Map Revision and a Letter of Map Revision. The portion of the project within the 100- year floodplain shall not be constructed until the Letter of Map Revision is approved by the Los Angeles County Flood Control District and FEMA.

In other words, Caltrans and Metro expect the public and public officials to comment on and/or accept a draft EIR that claims there won't be significant impacts before knowing what the determining agency says those impacts will be. This is recklessly backwards. We think it's terribly misguided to so cavalierly dismiss the impacts of potentially siphoning hundreds of dollars annually from working class and middle class families -- money that families could no longer use to help their children, pay for health care or spend at local businesses.

In the 1990s, when the Corps of Engineers decertified the L.A. river's 100 year capacity until levees were raised, FEMA imposed flood insurance on large parts of LB and southeast LA County miles from the L.A. river (image right).

The area that could be affected this time might be different due to multiple variables. The levees have been raised. Some bridges have been modified. Caltrans proposes to change some of those bridges and put multiple obstructions in areas that are now clear. What would all of those do?

When we asked Caltrans about this, an agency staffer said the 710 corridor design is still considered "very preliminary" and if and when it proceeds to final design, floodplain encroachments significant enough to require edits to FEMA's flood maps would be required.

No. The project proponents can't have it both ways. They can't create a plan behind closed doors pregnant with significant impacts, unleash it in a draft EIR/EIS that starts an unreasonably short public comment clock ticking (Caltrans is demanding written comments by Aug. 29) and then hide its significant impacts by pretending it's only preliminary. The impacts of their project won't be preliminary; they will likely be long-term. If the project is preliminary, it's not ready for an EIR...and if the project's proponents can't tell the public what impacts it will create, the draft EIR/EIS is inadequate on that basis alone.

We are constructively sounding the alarm here. Our intention is to avert a costly, long-term damaging outcome for residents, businesses and area cities. In our view, this will occur unless residents, neighborhood groups, business associations -- and especially elected officials -- insist that Caltrans and Metro make responsible changes that will conclusively avoid the damaging impacts their project now invites.

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