D-2 C15-2020-0029 LATE BACKUP — original pdf

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From: To: Subject: Date: Ramirez, Elaine comments C15-2020-0029 Aug 10 Friday, August 07, 2020 2:55:49 PM *** External Email - Exercise Caution *** Notes re variance request C15-2020-0029 coming before BOA this Aug 10, 2020 I would like to point out the following: 1. The "accessible attic" would be a 2nd floor occupiable space that would be accessed by an external staircase that would be situated in the westside setback. Though not shown on site plan it is shown on the elevation drawings. 2. In discussions with the owners they once expressed willingness to add a deed restriction eliminating the addition of a future 2nd story on the property. 3. The mid section of the proposed finished structure would have a gable height of 15 ft 6 inches above ground level***. This West facing facade would be 4 ft 2 inches from the mid lot property line. 4. One can't predict how promises of runoff control would play out in time. And I have no data to know if the promised containment strategies are feasible or accurate. *** This information was given to me, via email, by the owners as being data from the design firm(s) they consult .. "...numbers regarding height, coverage, and cistern. The high point of the roof gable is 15’6” -- that’s measured from the ground, not the foundation. Impervious percentage on the site plan is 57% -- the would only go down because it includes the flagstone walkway and we’d like to do decomposed granite for better drainage. Our cistern will be 1500-2000 gallons. At 1500 it would average out to 18000 gallons over the year. This water would go to our vegetable. We want it even bigger if it can fit, though the 1500 gallon one would already overcompensate for added impervious." Lou Rigler 1103 Toyath Street CAUTION: This email was received at the City of Austin, from an EXTERNAL source. Please use caution when clicking links or opening attachments. If you believe this to be a malicious and/or phishing email, please forward this email to cybersecurity@austintexas.gov. D-2/1 LATE BACKUPCapitol Tree Care, LLC 12407 N. Mopac Expy Ste. 250-123 Austin, TX 78758 512-913-6833 ArboristAustin.com C A P I T OL TREE CARE August 9, 2020 Subject: Tree Assessment Address: 1711 Waterston Ave Austin, TX 78703 Assessor: James Burtchell ISA Certified Arborist, TX-3593A ISA Texas Oak Wilt Qualified, TXOWQ-134 ISA Qualified Tree Risk Assessor To whom it may concern: I observed the trees at the above address on July 30, 2020, with regards to future home construction. While onsite, Mr. Ryan Bollom provided two home construction concepts and asked for my input on how such plans would affect the trees onsite and any neighboring trees that are close enough to experience effects. There is a Post Oak tree and a Pecan tree located on the property and two neighboring Hackberry trees and shrubs that are in close proximity to the current structures on-site, or will be within range of the footprint of the new construction. Within range accounts for canopies that will require pruning to accommodate the new structure or any critical root zones that will be encroached on by the foundation. Below are the two build concepts under consideration for 1711 Waterston Ave.: 1. Build a 2nd-story addition to the existing, home structure and extend farther back into back yard(front of house will remain 1-story), wrapping around Pecan tree 2. Build a 1-story home addition that will incorporate the additional structure in the back yard and extend farther back into the back yard, wrapping around Pecan tree A Post Oak is located on the left side of the front yard, close to the front left corner of the house. The front of the house will not change with regards to either renovation option listed below, so this tree will be unaffected. This tree is considered a “heritage” tree per the City of Austin tree ordinance. I have instructed Mr. Bollom to implement tree protection practices to protect the tree throughout the construction process. These protections include fencing and mulching as much of the critical root zone as possible, wrapping the trunk with 2x4’s and installing a drip-hose system over the fenced root zone for proper irrigation. A Pecan tree is located on the left side of the back yard, along the fence. The tree’s canopy extends over the back yard and over the neighbor’s property. The critical root zone of this tree extends into the back yard and also into the neighboring property. This tree appears to be healthy and vigorous. This tree has the ability to be effected by construction in different ways depending on the types of building methods used and tree pruning and protection practices implemented. D-2/2 LATE BACKUPThe right-side neighbor has two Hackberry trees and other shrubs located along the right-side fence of 1711 Waterston Ave. These neighboring trees extend over the right fence-line and hang over the current home, yard and detached building. The critical roots zones spread throughout the right side of the property as well. These trees and shrubs will also experience different effects depending on the practices and methods implemented. I believe these trees are not of “protected” status with regards to the City of Austin tree ordinance. Below are my observations and recommendations to preserve tree health and integrity based on the two concepts provided: POST OAK: Regardless of which build concept is chosen, the trees critical root zone will be unaffected as the current home foundation will remain unchanged. No pruning is required to accommodate any elevation changes to the structure. Install and implement proper tree protection methods and best management practices to protect tree and maintain and improve overall tree health and vigor. Proper fencing off of critical root zone will limit access over critical root zone with equipment, materials and foot traffic to avoid soil compaction and further adverse affects. PECAN: If the 2nd story addition concept is chosen, a large percentage of the canopy will require pruning to accommodate the new structure. As a rule-of-thumb, it is recommended to not remove more than 25% of live foliage from a tree, in a single pruning session. Excessive pruning can stress a tree and cause a tree to decline. Once a tree becomes stressed, it is susceptible to further secondary stressors such as pest and disease. Compounding stressors have the ability to severely impact a tree and threaten the overall health, integrity and mortality of a tree. With regards to the required pruning for a 2nd-story build concept, I recommend maintaining a low home elevation that will not require the tree to be severely pruned. Any build concept to reduce the amount of impervious cover of the critical root zone is also recommended, as impervious materials and grade changes have the ability to suffocate underlying roots. Practices such as cantilevers and pier-and-beam foundations have less intrusive impacts within the critical root zone and reduce the overall percentage of impervious cover. Excavating with a Airspade tool within the critical root zone will also help to preserve roots and allow building practices that will cause less impacts to the roots and tree. Design the footprint of the new foundation to stay as far out of the critical root zone as able. Branch Removal Branch Removal D-2/3 LATE BACKUPPecan tree with required pruning cuts for clearance D-2/4 LATE BACKUPNEIGHBOR’S HACKBERRY TREES AND SHRUBS: There are neighbor’s Hackberry trees that hang over the back right corner of the existing home and over the right side of the detached structure in the back yard. If the 2-story addition concept is chosen, the trees will require substantial pruning to accommodate the new structure. As notated with the Pecan tree, excessive pruning can cause stress on a tree, impacting the overall health and vigor. Pruning to accommodate the structure can also imbalance the canopies, which could affect the tree’s structural integrity. I recommend the single-story build concept to maintain the health, structure and aesthetic integrity of the neighbor’s Hackberry trees and other shrubs along the fence-line. D-2/5 LATE BACKUP