Traffic Mitigation Proposed

How is traffic mitigated on Courtyard and 360


Per the HDR Traffic Impact Assessment 1) Construction of an additional eastbound turn lane on W. Courtyard Drive by modifying the existing median. 2) Construction of an acceleration lane on Loop 360 allowing eastbound right turns from W. Courtyard Drive to be free-flowing. This would require traffic to merge into southbound Loop 360 traffic prior to reaching the Loop 360 Bridge and coordination with TxDOT will be required to obtain approval of the design. 3) Construction of an additional northbound left-turn lane to provide dual left- turn lanes. The left-turn lanes will be extended to provide the City of Austin minimum 100 feet storage and taper lengths. 4) Removal of pedestrian phasing on the north side of the intersection (crossing Loop 360) to reduce green time for the westbound approach. (Improvement does not affect analysis results presented in this TIA. Pedestrians would still be allowed to cross Loop 360 on the south side of the intersection.) 5) Signal modification (pole relocation and installation of steel mast arms) and timing optimization. No additional improvements are recommended at this intersection as part of this project as the impact of site traffic has been mitigated for all traffic movements; however, as a result of these short-term improvements, the eastbound approach experienced improved delay times; 78 seconds/vehicle to 50 seconds/vehicle and 267 seconds/vehicle to 116 seconds/vehicle during the AM and PM peak periods, respectively. It should be noted that this intersection is also part of the TxDOT Loop 360 Improvement Study, which calls for grade separation and removal of the signal. In the long-term TxDot will provide this intersection with significant improvement.




How is traffic mitigated on City Park Road and 2222?


Per the HDR Traffic Impact Analysis 1) Construction of an acceleration lane on RM 2222 allowing northbound right turns on City Park Road to be free-flowing. It should be noted that a significant cost would be associated with this improvement due to the existing grade off the current edge of pavement and the presence of underground utilities, as discussed during the Champion Tract 3 TIA review process. The available distance between City Park Drive and the bridge to the east is 900 feet, and coordination with TxDOT will be required to obtain approval of the design. 2) Restriping the westbound left-turn lane to extend the storage length to 700’ to accommodate 95th percentile queuing. 3) Signal modification (pole relocation and installation of steel mast arms) and timing optimization. No additional improvements are recommended at this intersection as part of this project as site traffic has been mitigated for all traffic movements. Site traffic comprises approximately 4.6 and 4.5 percent of total traffic at the intersection during the AM and PM peak periods, r




How is traffic mitigated on Bridge Point Parkway and City Park Road?


The Traffic IImpact Assessment (TIA) states “The delay for each approach lane group is calculated based on a number of factors including lane geometrics, percentage of trucks, peak hour factor, number of lanes, signal progression, volume, signal green time to total cycle time ratio, roadway grades, parking conditions, and pedestrian flows.” “Because delay is a complex measure, its relationship to capacity is also complex. The City of Austin considers overall intersection levels of service A to D to be acceptable, while overall LOS of E and F is unacceptable.” As we all know 2222/CPR is LOS F. Fortunately, TxDot will make improvements and so will Jonathan. The Bridgepoint Pky intersection is calculated at LOS A and the average control delay is expected to be minimal. Despite the numbers not requiring mitigation at Bridgepoint and City Park, Jonathan will add a left turn que lane on City Park Road into Bridgepoint for increased safety.




Describe the design of Bridgepoint Parkway


Bridge Point Parkway and Cold Water Canyon Drive The proposed Bridge Point Parkway extension will form the third leg of this T-intersection, which will be constructed as a one-lane roundabout, as shown in Figure 3. This intersection will operate at LOS A under the 2022 site plus forecasted traffic conditions during both the AM and PM peak periods. No improvements are recommended at this intersection as part of this project as all traffic movements are operating acceptable levels of service. Site traffic comprises approximately 76.9 and 62.8 percent of total traffic at the intersection during the AM and PM peak periods, respectively. Driveway A and Bridge Point Parkway Driveway A should be constructed as a stop-controlled approach with a minimum 30-foot cross-section that provides one inbound and one outbound lane. Driveway A will operate as one of the two primary access points for the proposed residential development. This intersection will operate at LOS A under the 2022 site plus forecasted traffic conditions during both the AM and PM peak periods. The westbound approach of this intersection will operate at LOS A with no queue under 2022 site plus forecasted traffic conditions Traffic Impact Analysis Camelback April 23, 2018| 23during both peak periods. Based on the available capacity at this approach and the volumes for the westbound left-turn movement (1 and 3 during the AM and PM peak periods, respectively), a separate westbound left-turn lane was not recommended. Driveway B/Driveway C and Bridge Point Parkway Driveways B and C should be constructed as stop-controlled approaches with minimum 30-foot cross-sections that provide one inbound and one outbound lane. Driveway B will operate as the primary access point for the proposed office development, while Driveway C will operate as the other primary access point for the proposed residential development. This intersection will operate at LOS A under the 2022 site plus forecasted traffic conditions during both the AM and PM peak periods. Driveway D and Bridge Point Parkway Driveway D should be constructed as a stop-controlled approach with a minimum 30-foot cross-section that provides one inbound and one outbound lane. Driveway D will operate as the primary access points for the proposed restaurant development. This intersection will operate at LOS A under the 2022 site plus forecasted traffic conditions during both the AM and PM peak periods.The roundabout improvement proposed at the request of the City will be located at the existing intersection of Coldwater Canyon Drive and Bridge Point Parkway. It will be a sinlge-lane roundabout. The details will be proved later at the site plan stage.




How will traffic be impacted?


Although trips are used as a primary descriptor, they are not the most important indicator. Level of Service (LOS) and hence the delay we experience at intersections is the most important. LOS "A" is free flowing traffic with less than 10 seconds of delay, LOS "F" is bumper to bumper with delays of greater than 20 seconds.

The LOS for 2222/CPR is F with Senior Living or with the Apartments. All calculations show Bridgepoint Pky at LOS A.

Once Bridgepoint is built, it will have a large increase in trips primarily due to office uses, but the LOS for CPR/Bridgepoint shows minimal delay and hence minimal driver frustration is expected. To evaluate traffic, there are two key factors 1) the amount of traffic on the road at a particular time and 2) the time waiting in queue.

The PUD site generated traffic, or the traffic that will be created due to the development of the proposed PUD project, is estimated to generate approximately 5,808 unadjusted daily trips upon build-out. The Multifamily housing is for the Townhomes and Condos. The restaurant, in all likelihood, will have opposable traffic flow to the office, but it is all lumped together on this chart. This chart shows the total number of trips and how many trips will be in the AM (7:00-9:00am) and how many in the PM (4:00-6:00pm).

The TIA limits the amount of trips to 5,808 so no matter what is built on the PUD the trips cannot exceed the limit.

Here's a summary of what is being done by Jonathan to improve the traffic. His costs will be over $2,000,000 to improve the intersections.

Below is a detailed summary of traffic production, which is directly related to the assumed land use plan. The "A" to "F" refer to the calculated Level Of Service (LOS). LOS is the standard used to evaluate traffic conditions at intersections, which is a qualitative measure of the effect of a number of factors such as “speed, volume of traffic, geometric features, traffic interruptions, freedom to maneuver, safety, driving comfort, convenience, and operating cost”. “A” means good progression and short cycle lengths, “F” mean unacceptable to drivers, volume great than capacity.On the traffic, although trips are used as a primary descriptor, they are not the most important indicator. Level of service and hence the delay we experience at intersections is the most important. The LOS for 2222/CPR is F with Senior Living or with the Apartments. All calculations show Bridgepoint Pky at LOS A (at “forecasted”, or at “forecasted with or without improvements”). Once Bridgepoint is built, it will have a large increase in trips primarily due to office uses, but the LOS for CPR/Bridgepoint shows minimal delay and hence minimal driver frustration is expected.

The 2022 Forecasted is the existing plus expected cut through traffic by 2022 due to normal growth (what we can expect traffic to be like in five years without the PUD), the last column shows the impact of the PUD with mitigated (improved) intersections.




How much traffic is there now at surrounding intersections?


Note there are 51,700 trips on FM 2222, 5,900 on City Park Road by the Champion Tract 3, and 7,300 on West Courtyard and 360, and 43,900 on Southbound 360. Although trips are used as a primary descriptor, they are not the most important indicatior. Level of Service (LOS) and hence the delay we experience at intersections, is the most important. LOS for 2222/CPR is F with senior living or with the Apartments. All calculation show Bridgepoint Parkway at LOS A when the PUD is fully built out. THe PUD will generate trips, primarily due to the two offices, but City Park Road and Bridgepoint are shown in the Traffic Impact Assessment to have minimum delay time, and hence minimal driver frustration. For further details see the questions below.





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