CV Link and the Environment, part 2 geologysoils

Geology and soils

The CV Link is located in an area susceptible to landslides at one location, adjacent to Point Happy at the Indian Wells/La Quinta boundary. The Point Happy rock face will be evaluated and scaled of loose rock from the exposed slopes. Rock catchment devices, such as walls or steel mesh will be installed to mitigate the rockfall hazards.

Implementation of the CV Link could result in soil erosion or the loss of topsoil. Ground removal and recompaction of loose, near surface sandy soils will minimize dynamic settlement of dry soils. Deep dynamic compaction, additives (cement or fiber) to the soils and flooding of loose, granular soils will increase the density of the fill and remove or reduce the tendency to settle under dynamic shaking. Deep foundations will be considered at bypassing zones of loose sand.
Utility trench excavations in slope areas or near structures will be backfilled in conformance with governing agencies (water district, public works department, etc.). Backfill operations will be tested to monitor compliance.
Slope protection, cutoff walls, deep foundations below the maximum depth of scour and comparable measures will be applied.
Grading activities will cease during rainstorms or high wind events. Flow barriers and soil catchments (such as straw bales, silt fences, and temporary detention basins) will be installed during construction to control soil erosion.

Portions of the CV Link could be located on expansive soil, as defined in Table 18-1-B of the Uniform Building Code (1994), creating substantial risks to life or property. CV Link design and engineering will conform to the prevailing California Building Code (CBC) for buildings and other structures, and Caltrans design standards for bridges to mitigate the effects of groundshaking and earthquake damage.
Foundation designs and subsurface soil improvements will follow the California Code of Regulations Volume 18, Title 14, Article 10, Section 3721[a]) to minimize liquefaction hazards. The design measures will avoid overexcavation and hydrocompaction, and include remedial grading, strengthening and deepening structural foundations.
All grading plans will include a soil erosion prevention/dust control plan. Blowing dust and sand during grading operations will be mitigated by adequate watering of soils prior to and during grading, and limiting the area of dry, exposed and disturbed materials and soils during these activities. After site development, measures (moist surface soils, planting stabilizing vegetation, establishing windbreaks with non-invasive vegetation or perimeter block walls, and using chemical soil stabilizers) will be installed.
Unprotected, permanent graded slopes will not be steeper than 3:1 (horizontal:vertical) to reduce wind and water erosion. Protected slopes with ground cover may be as steep as 2:1. Fill slopes will be overfilled and trimmed back to competent material. Fill slope surfaces shall be compacted to 90% maximum density either by over-filling and cutting back to expose a compacted core or by mechanical methods.
Positive site drainage shall be established during finish grading, for 2% away from structures for a minimum of 3 feet and a minimum gradient of 1% to the street, channel or other approved
drainage course.
Dust control measures will be implemented to control wind-blown sand during construction, in compliance with the SCAQMD and the Coachella Valley PM10 SIP.
Excavated soils may be used as fill material if they are free of organic or deleterious matter. Rocks or concrete larger than 6 inches will be removed from fill or backfill material. Prior to integrating reconditioned fill soil, the areas will be scarified, brought to optimum moisture conditions, and recompacted to at least 90%.
Any imported soils will be non-expansive, granular soils meeting the USCS classifications of SM, SP-SM, or SW-SM with a maximum rock size of 3 inches and 5 to 35 percent passing the No. 200 sieve. Imported fill shall be placed in maximum 8-inch lifts (loose) and compacted to at least 90 percent relative compaction (ASTM D 1557) near optimum moisture content.
Excavations of sandy soil will be kept moist, unsaturated, to reduce caving or sloughing. Where excavations over 4 feet deep are planned, lateral bracing or appropriate cut slopes of 1.5:1 (horizontal/vertical) will be provided. No surcharge loads from stockpiled soils or construction materials shall be allowed within a horizontal distance measured from the top of the excavation slope and equal to the depth of the excavation.
Removal and recompaction of susceptible soils, flooding and surcharging, and/or other ground densification techniques will mitigate hydro-collapse potential.
Standard geotechnical practices such as excavation of the expansive soils and replacement with non-expansive compacted fill (by using additional steel reinforcing in foundations, post-tensioned slabs, presoaking, and drainage control devices) will be used.

La Quinta candidates' answer about CV Link

Updated 2016.11.09
The editorial board of the Desert Sun asked this question of all candidates for City Council:

"Are you in favor of La Quinta being part of the CV Link? Why or why not?"

Here are the Mayoral candidate responses:

• Linda Evans, winner 2016 with 83%: "I support La Quinta being part of the CV Link. It provides a safe route for cyclists, runners, and walkers. It offers the option to take cars off the roads, resulting in less environmental impact. It provides a safe, free passage for a healthy lifestyle, like our other hiking/biking trails and parks. It connects our valley as an alternative transportation option, allowing access to shopping, dining, schools, and other amenities. The two-mile plus stretch in La Quinta will be one of the least impactful sections; the route is visible and non-intrusive to private areas. The maintenance costs will likely be similar or less than the City’s current spend on Bear Creek Trail and Cove hiking trails. Many states across the country have similar paths that are used for transportation, recreation, and tourism. I invite people to walk LQ’s section with me and experience its potential for our city and valley. "
  
  I endorse this wholehearted support of CV Link and the safe corridor it will provide for all types of alternative transportation. Evans' insight that CV Link has benefits similar to a park shows her flexibility and foresight.
  
  
• Paula Maietta, not winner 2016: "Based upon the information we have, no, I am not in favor of this project. When do these ridiculous Council decisions end?  Construction cost is estimated at $100 million, and CVAG does not know where all that money is coming from. I believe that this project will provide greatest benefit to Goldenvoice/AEG and their concertgoers.  Let’s privatize this project and contract it out to them, like the toll roads.  This should be a decision made by the voters who will be paying maintenance costs for this boondoggle, as we are for Silverrock.  There’s discussion that the additional money needed for this project might come from TOT taxes; here we go again.  Our TOT taxes will go to this project instead of into our general fund to pay our bills, so the City will propose a TOT tax increase to make up for that loss. And on and on it goes."
  
  Maietta reveals an insular and provincial attitude as well as the fact she hasn't become informed about the project. Likely she has heard and bought into the Hobart Boondoggle and its misleading arguments against CV Link.
  
  

 Here are the council candidate responses:

• Kathleen Fitzpatrick, winner 2016 with 24%: "I think the CV Link would be great for La Quinta. It would be a complement to our brand promoting healthy living. In La Quinta the CV Link would also open up commercial opportunities along the back of the 111 corridor to Link users. However, while we need recreational opportunities that increase our activity and enhance tourism, we need to fully evaluate the costs of maintenance of the trail for the City. In light of our other economic challenges we need to be sure the link can be maintained before we commit to construction."
  
  Fitzpatrick seems to be a qualified supporter, and it might help her to read Section 8 of the CV Link Conceptual Master Plan, which offers over 20 sources to combine for funding O&M costs.
  
  
• Kristy Franklin, not winner 2016 with 22%: "I am not going to vote for this project without knowing what it will cost my taxpayers to maintain it. When we spend tax dollars, there will always be some citizens who benefit indirectly, and in the case of CV Link it appears that most of our residents would fall into that category. I’ve been asked by the Cove and Southside citizens why they would want to drive such a distance to ride bikes, walk, run, etc. when La Quinta already has great trails and bike lanes. In addition arteries moving southward from the Link would have to be built and maintained by the City."
  
  Franklin has not yet considered cycling and neighborhood electric vehicles as transportation. To her, they are merely another leisure activity, and it seems she believes leisure can be relegated to isolated areas that already exist.
  
  
• Joe Johnson, not winner 2016 with 14%: "The CV Link is not a terrible idea for a bike path.  It isn’t suitable for pedestrians, walking dogs on hot concrete, or for electric carts.  The proposed section going through La Quinta is troubling.  The limited access here makes it almost useless for anything except bike riders.  We have a new item, maintenance.  This will cost us another $100,000-$250,000 a year, not including the cost of Sheriff patrols (this is just like any other street and needs constant patrol).  Due to its desolate environment and 24-hour access, our few miles are just a problem waiting to happen."
  
  Johnson has freely expressed his opposition to CV Link elsewhere, and he seems to revel in the half-truths expounded by other opponents. I must correct his statements about the cost of maintenance: The project document (CV Link Conceptual Master Plan, Section 8) lists over 20 sources of funding for O&M costs, which are estimated to be about $10K to 30K per mile annually. These O&M costs include maintenance, safety and security patrols, marketing and events, insurance and risk management, and general management.
  
  
•  Victoria Llort, not winner 2016 with 18%: "CV link is an innovative concept that, when realized, would benefit the Coachella Valley as a whole. Due to La Quinta’s 10 year projected $50 million deficit, all financial costs must be considered. Currently, CVAG (Coachella Valley Association of Governments) is not requesting any funding from participating cities for construction or maintenance of CV Link; foreseeable maintenance expenses are estimated to equal Bear Creek Trail in La Quinta. CV Link would be a great addition that brings potential for La Quinta and tourism enthusiasm."
  
  I appreciate Llort's considered, deliberate approach. I believe she would fully support CV Link after she has pored through the CV Link project document.
  
  
• Steve Sanchez, winner 2016 with 22%: "I love waking up at 0400 to run my dogs, workout, or go for a long run; I try to do a half marathon every few months. At first, I was 100% opposed to La Quinta being a part of CV Link; I felt it was a waste of money. But, after learning more about CV Link, how La Quinta’s portion will be funded, I’ve had more of an open mind to it. As a La Quinta City Council member I would never tell another city what they should do, but for La Quinta, I want to see what the EIR report says."
  
  Sanchez would be a valuable voice for those who hope to see CV Link come to La Quinta.
  
  

Of course, there were other questions. See more at the Desert Sun Election Questionnaire.