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HomeMy WebLinkAbout13.F.1. Set Workshop Date for First Avenue Discussion I~. F. J. CITY OF SHAKOPEE Memorandum TO: Mayor and City Council FROM: Mark McNeill, City Administrator SUBJECT: Workshop-First Avenue DATE: January 13, 2009 Comment: Introduction: The City Council has asked to establish a special workshop for Tuesday, February 24th, to discuss the future of First Avenue. Background: Discussions have been held recently between the Cities of Shakopee and Chanhassen about possible improvements to the CR 101 Bridge, and how that structure and roadway might be upgraded to become a year-round river crossing, with additional traffic capacity. . The week of January 12th, Scott County hired a consultant to look at the future of First Avenue, which is scheduled for reconstruction during 2010. Combining both issues- impending reconstruction, and CR 101 river crossing improvements--indicates that the City of Shakopee needs to make some determinations on the future of 18t A venue, and adjacent land uses. A preliminary study done by SRF for Scott County showed that improvements to the CR 101 Bridge will greatly increase the amount of traffic on 18t A venue, to the point that it would be significantly over its capacity for the existing four lane roadway (see attached report). Currently, there are about 17,000 vehicles per day (Average Daily Traffic) on 18t Avenue. Without any changes at all to the CR 101 bridge, ADT's are expected to increase to 30,000 by 2030 (for a perspective, prior to the opening of US 169 in 1996, ADT's on this segment of roadway were in the 20,000 to 25,000 range). With improvements to the CR 101 bridge as contemplated, ADT's will be 45,000 to 50,000. We see that as being unworkable for traffic flow, and for many types ofland uses in the corridor. If the City and Scott County are to continue to pursue improvements to the river crossing, decisions need to be made in terms of what 18t A venue and surrounding land uses will be. Obviously, working within existing rights of way, and accesses to and from businesses will be crucial to consider. At staff level discussions with Scott County, we have identified Tuesday, February 24 as a possible workshop date to put these issues on the table, and hopefully get some direction from the City Council. We recommend a 7pm start. Relationship to Visioning: This supports Goal D, "Vibrant, Resilient, and Stable". Recommendation: I recommend that the workshop be scheduled as suggested. Action Required: If the Council concurs, it should, by motion, establish a workshop for Tuesday, February 24th at 7pm to discuss First Avenue traffic and land use issues. VtV law1i1 Mark McNeill City Administrator ~.c ONSULTING GR OUP, INC... I MINNFAroUS FARGO E N .C ! NEE I<sl PLANNERS I D ES Ie N E RS MADISON SRF No. 0086538 0240 DRAFT MEMORANDUM TO: Lisa Freese, Transportation Program Manager FROM: Stephen C. Wilson, Principal DATE: November 19,2008 SUBJECT: TH 101 Bridge Traffic Forecast Assessment As you requested we reviewed the forecast 2030 travel patterns and effects from various scenarios of TH 101 using the Scott County traffic model, which was modified to better reflect he alternatives considered in the TH 101 Screening Study. Three model runs were considered in our analysis . Base (no improvements to TH 101 in Carver County or Scott County) . Four-lane Carver County (assuming a best-case interchange configuration at TH 101 and "old" TH 212) . Four-lane Carver County plus four-lane Scott County TH 101 Our analysis shows that increasing the capacity on TH 101 in Carver County, including improvement to the junction ofTH 101 and Old TH 212 would increase traffic across the Minnesota River at TH 101 by improving access to the ChaskalChanhassen area as well as improving connectivity to new TH 212. Increasing the capacity of TH 101 across the Minnesota River to four lanes, would increase further increase demand. Assumptions Roadway and land development assumptions used are consistent with those described in the Scott County Transportation Plan. Most significantly, the land assumptions for 2030 are consistent with the Metropolitan Council's travel demand model as of January, 2007. Roadway assumptions include the adopted regional transportation plan, along with planned and programmed Scott County roadway improvements. A 2007 study of TH 101 in Chanhassen concluded that a "central" alignment with a more direct connection and interchange at the intersection with "old TH 212" was viable. This analysis is based on generalized assessments of capacity, whiCh would need to be conf'rrmed using more detailed operations analysis. This assessment assumes that any new construction would be designed to accommodate demand. Www.srfconsulting,com One Carlson Parkway North, Suite 150 I Minneapolis, MN 55447.4443 I 763.475.0010 Fax: 763.475.2429 .4/1 Equal Opporhmity Employer Lisa Freese -2~ November 19,2008 River Crossing Demand Table 1 shows the 2030 forecast ADT on the TH 101 and adjacent river crossings. Expanding TH 101 in Chanhassen alone would increase volumes on the TH 101 Bridge by approximately 2,100 vehicles per day, the result of capacity limitations on the bridge. Expanding the bridge/causeway to four lanes and making appropriate improvements to the intersection at the south end of the bridge would increase traffic by over 22,000 vehicles per day (vpd) resulting in a forecast volume of 52,300 vpd assuming no capacity constraints at the bridge approaches on the north and south ends. This value reflects a large unserved demand between Scott and Carver Counties, which is consistent with previous conclusions in the TH 41 Study. While traffic volumes would be drawn largely from the TH 41 and TH 169 crossings, most of the volume reduction would be offset by "backfilled" demand from other river crossings; the result of the general river crossing capacity shortfall in the south metropolitan area. Consequently there is a net increase in traffic across the three bridges in the immediate study area. Table 1 2030 Forecast Average Daily Traffic at Selected Minnesota River Crossings 2030 4-Lane 4-Lane Carver/ Existin2* Base Carver Scott TH41 16,500 25,000 23,700 22,100 TH 101 20,600 30,000 32,100 52,300 TH 169 50,000 120,000 120,000 113,500 Total** 87,100 175,000 175,800 187,900 * MnDOT 2007 Traffic Flow Maps **Includes traffic attracted or 'back-filled' to corridor Market for Expanded TH 101 The additional Scott County traffic using TH 101 consists primarily of demand to or from Shakopee, with an estimated 13,000 trips (59 percent of the total). Of those trips, most (9500 vpd) would be expected to come from the portion of Shakopee north of TH 169, with the remainder These are trips that generally were taking more circuitous routes to reach destinations on the north side of the Minnesota River (45 percent in Chanhassen). It should be noted that a portion of the demand from south of TH 169 (approximately 1000 trips)come from south of Shako pee. Demand from the TH 169 south of the Shakopee area is not projected to be a major component of the traffic (3000 vpd). In general, those trips are better served by accessing the recently completed TH 212 via the TH 41 bridge. A more significant component of traffic would be previous users of the TH 169 river crossing, with a net increase of 5000 vpd increase on CSAH 101 coming into the Shakopee area from the Savage, Prior Lake and Burnsville areas. Lisa Freese -3- November 19,2008 +221000~ TH10l Figure 1 Distribution of 2030 Net Traffic Demand Increase on Four-Lane TH 101 River Crossing Affected Scott County Roadway System Forecast (2030) traffic volumes will be limited by the capacity ofintersectionlinterchange control at the north and south approaches to the bridge. The bridge/causeway itself is a two-lane rural design with very minimal access. Consequently, its capacity can approach approximately 2000 vehicles per lane per direction per hour. However, there may be capacity constraints at the approaches to the bridge. .The base 2030 forecast for CSAH 101 east of the river crossing is for volumes of 20,000 to 30,000 vehicles per day. The estimated additional traffic on the east approach to the bridge on CSAH 101 is as high as 13,500 vpd, which could result in ADTs ranging from 30,000 to 45,000 vpd on CSAH 101. Traffic in this range would generally be expected to approach or exceed the capacity of the roadway, pending on factors such as access spacing and local roadway geometry. Additional analysis would likely be needed to determine the impact on north-south collectors and arterials, in particular Spencer Street and Marschall Road. Lisa Freese -4- November 19, 2008 2050 Implications A test scenario was run using the Scott County 2050 model to determine whether the improved TH 101 river crossing would have a significant effect on a new TH 41 river crossing. For the purposes of this analysis alignment "C-2" was selected for TH 41. Two significant findings emerge from the analysis: . In this exercise, a new TH 41 River Crossing is forecast to carry 72,000 vpd. Of that volume, 14,000 vpd (19 percent) would be diverted from a four-lane TH 101 bridge. This indicates that the market for a new TH 41 river crossing is generally different than that of the TH 101 crossing. . The forecast 2050 volume at the TH 101 river crossing is 58,000 vehicles per day, even with a new TH 41 river crossing. This indicates traffic demand exceeds the capacity of a two-lane bridge regardless of the presence of a new TH 41 River Crossing. Figure 2 illustrates the demand patterns for the TH 101 crossing and that portion of the TH 101 demand that would be diverted to a new TH 41 crossing by 2050. The demand is better served by the TH 41 crossing, and logically would only be on TH 101 because of a capacity shortfall at the existing TH 41 bridge. These estimates are based on an "illustrative scenario" ofland development for Scott County. It should be noted that the TH 41 EIS assumed a 2040 population of247,000 for Scott County, whereas the 2050 scenario assumed 357,000. Consequently, direct comparisons to the forecasts from the TH 41 EIS would be difficult. ......,.. - TH 101 Demand Divprt",cl to Npw TH 41 , J\ > { {. r Figure 2 Year 2050 Travelsheds