SOSSAMAN CLOUD PARK. Site Conditions

Transcription

1 SOSSAMAN CLOUD PARK distant views of the Superstition Mountains to the northeast. A series of dirt roads are visible throughout the site and trash and debris from local neighborhoods are present. A graded air strip is located from the northwest corner and runs diagonally to the southeast corner. This site is proposed as a storm-water retention basin site to accommodate drainage flows from the areas south of the site. Volume and configuration will have a significant impact to the landform of this site (Figure 27). Sossaman Cloud Park will be a passive dog park approximately 20 acres in size. The park site is located east of Sossaman Road and approximately 126 yards south of Cloud Road. The surrounding land use, at the time of this master plan document, is residential. Directly to the north of the site, another residential development is planned along with a Queen Creek School District Middle School to the south. Site Conditions The existing site is characterized as flat. native desert terrain, which drains gradually to the northwest. The Sossaman Cloud Park site has magnificent view of the San Tan Mountains to the southwest, south and southeast and Location: The park site is located in the southwest ¼ of Section 29, Township 2 South, Range 7 East. Figure 27 45

2 the full extent of the park. Refer to Appendix F: Initial Geologic Evaluation, for a full explanation of the geology/soils review. Vegetation: The park site is currently covered with native vegetation, consisting of mesquite, creosote scrub brush. Drainage Conditions: The site has a gradual slope to the northwest with a 0.1 percent gradient. Acreage: 20 acres Topography: The site consists of relatively flat, native desert terrain which drains gradually to the northwest at approximately at 0.1 percent gradient. The average elevation of the site is approximately 1,385 feet. Surrounding Land Uses/Zoning: The park site and the adjacent properties are currently zoned R-143, which allows for residential lots of 43,000 square feet. The property directly to the south of the site is designated to be a middle school managed by the Queen Creek School District. Site Access: Sossaman Road will most likely provide primary access to the Sossaman/Cloud Park site. Secondary access for local users could be permitted through Vallejo Street in the San Tan Vista Ranch Subdivision. Views: The park site has magnificent views of the San Tan and Goldmine mountains to the southwest, south, and southeast and distant views of the Superstition Mountains to the northeast. Historic/Cultural Features: The abandoned airstrip on the site was an auxiliary air strip that had been developed by the Hawes family, who had once owned this property. The air strip had been used for the Hawes family s personal use. Refer to Appendix E: Cultural Records Review, for a full explanation of the cultural review. Environmental Issues: No known significant environmental issues exist on the park property. Soils/Geology: The surficial soils of Sossaman and Sossaman Cloud Park generally consist of Holocene alluvial fan, terrace, and ephemeral stream channel deposits. According to the NRCS, the surficial soils at the proposed Sossaman and Cloud Park are classified as Gm, and cover Infrastructure and Utilities Water: The Queen Creek Water Company owns an existing 8-inch water line in Sossaman Road. This water line would provide the most direct water service to the Sossaman/Cloud Park. 46

3 half street right-of-way. Vallejo Street is a local roadway and will not be widened. Sewer: Currently, there are no sewer lines in the vicinity of the Sossaman/Cloud Park site. The plans to extend the 18-inch sewer in Sossaman Road, which is to be constructed with the Sonoqui Wash Channelization project. The proposed sewer line would extend to the new school to be located south of the park site. This proposed pipeline would provide service to the park and is anticipated to be constructed by July Storm Drainage: The Sossaman Cloud Park site will drain to the basin located within the park. The park will function as an off-line retention basin. A channel will be constructed along the west boundary of the park. The channel will have a capacity of 700 cfs. The park will have a lateral weir that allows flow up to 400 cfs to continue north; the remaining 300 cfs are diverted into the basin. It is anticipated that 400 cfs is roughly equivalent to a 10-year storm event (i.e., the park will be dry for events up to a 10-year event). During the 100-year event the park will fill to a depth of approximately 6 feet. The water must infiltrate into the ground. Geotechnical testing has not been performed at the park site. The testing would provide estimates of the infiltration rate of the soil (i.e., how long it will take to drain the basin). Typically, a 3-foot-deep basin is designed to drain in a maximum of 36 hours. It is anticipated that dry-wells will be required to decrease the time the park is submerged. Roadways: The Sossaman/Cloud Park borders vacant properties to the north and south, the San Tan vista Ranch Subdivision to the east, and Sossaman Road to the west. There are two existing roadways that could provide access to the park: Sossaman Road and Vallejo Street. Sossaman Road is a 2-lane, 26-foot-wide roadway, which fronts the entire western boundary of the park site. The posted speed limit is 45 miles per hour, and the existing half street right-of-way width is 33 feet. Vallejo Street tees into the east side of the park from the San Tan Vista Ranch Subdivision. Vallejo Street is a local street that is approximately 26 feet wide, with 50 feet of right-of-way. There are no known improvements planned for either Sossaman Road or Vallejo Street. This section of Sossaman Road is classified as a Major Collector consisting of 2 lanes at the ultimate build-out and requiring 40 feet of The park features will be designed to accommodate the 100-year ponded depth. However, the basin will not receive off-site stormwater for events less than a 10-year storm. Any steel ramada roof structures in the basin zone will be elevated to be out of the highwater level. The columns, which will support the ramada roof structures, may be constructed 47

4 out of CMU block (concrete masonry units) or cast concrete piers. The chain link fencing in the dog park zones will be submerged during the 100-year event. In terms of de-watering the basin after a major flood event, it is anticipated that a permanent pump station would not be a cost effective option for the Town. However, the Town could rent a portable pump to assist in the de-watering of the park. This would likely be a once every-few-year occurrence. Future geotechnical testing will provide estimates of the infiltration rate of the soil, which will allow the Town to determine how long it will take to drain the basin. Refer to Appendix G: Utility/Roadway Access Report for a full explanation of utility analysis. Site Opportunities and Constraints Site features and conditions have been identified during the data collection and site analysis phase that have influenced the design of the park (Figure 28). Site Opportunities: Sossaman Cloud Park is nestled within neighborhood communities with outstanding mountain views of the San Tan and Superstition mountain ranges. The park will offer useable open space not only to the residents in the immediate area but also the school and students in the adjacent Middle School. The planning of a 2-acre fire station with a police substation on the northern corner of the site, adds to the overall security and safety of the park. Site Constraints: The Sossaman Cloud Park site will serve as an off-line detention basin with the capability of containing 50-acre-feet of water (approximate size 700 feet by 700 feet) in a 100-year storm event. A 30- to 35-footwide concrete storm drainage channel that is proposed along the east side of Sossaman Road the entire length of the site will be designed to convey flows of 300 cfs. Flows in excess of 400 cfs shall be diverted into the detention basin located on the park site. In association with the park design, a lateral weir spillway will need to be designed to safely divert flows into the park, and an outlet pipe will need to be designed to allow flows to slowly leave the park. A 20-foot-wide earthen storm drainage channel also is proposed to run along the east and north sides of the site to handle retention. The site is located in an established residential area of Town. Town policy is to not allow high-mast ballfield lighting in these established neighborhoods. This precludes the use of sports field lights on this site. Recreational Facilities Program Recommendations from the PTOSMP and the Committee: Primary amenities for the Sossaman Cloud Park site were identified in the PTOSMP. During the planning process the PTOS Committee participated in refining the items outlined in the PTOSMP and identified the following amenities for the Sossaman Cloud Park site: Baseball/softball fields Covered play grounds Dog park Lake or water feature Ramada/picnic areas Skate/BMX Park Soccer fields Walking/hiking trails Recommendation from the Public: Many of the comments received corresponded with 48

5 Figure 28 49

6 items outlined in the PTOSMP and identified by the Committee. In general, all types of playfields (baseball, softball, football, soccer, etc.) were in high demand for an active-use park and ramada/ picnic areas and walking/hiking trails were in demand for a passive-use park. Sossaman Cloud Park was originally programmed to be an active-use park. Master Plan Alternatives Through the combined efforts of the Committee and the planning team, three design alternatives were developed for the park site. These alternatives were presented to the public for review and comment. Alternative A Primary Features (Figure 29): A 30 to 35 feet wide concrete storm drainage channel Drainage weir 20-foot-wide earthen storm drainage channel 6-foot-deep retention basin (50-acre feet) to accommodate a 100-year storm event Planned fire station Ingress/egress off Sossaman Road A skate/bmx facility Multi-use trail w/group ramada and two picnic ramadas Sizeable plaza equipped with a play area, four picnic ramadas, and restroom building Parking for 120 vehicles Figure 29 50

7 Advantages: The intent of the park design was to give youths an activity (skate/bmx) and still allow ample open space, shade trees, trails and play areas with limited noise and low lighting near residents to the east. By locating the skate/bmx facility near the fire station, the fire and police departments would then have the opportunity to observe all activities. By locating the facility by Sossaman Road, the noise of the skate/bmx would be reduced and not intrude on existing neighbors to the east. The lush green turf open space between the skate/bmx facility and plaza served as a buffer between residents and the activities and could provide recreational opportunities. Disadvantages: There was some concern that having a skate/bmx facility in the area would create excessive noise and crowds. The parking wrapped around the fire station and visibility could have been a problem. Alternative B Primary Features (Figure 30): 30 to 35 feet wide concrete storm drainage channel Drainage weir 20-foot-wide earthen storm drainage channel 5-foot-deep retention basin (50-acre feet) to accommodate for a 100-year storm event. Planned fire station Ingress/egress was off Sossaman Road Sizeable plaza with a play area, a group ramada, two picnic ramadas, and a restroom building Three 1-acre fenced dog park zones with each Figure 30 51

8 containing its own ramada Large open turf area was provided for play Multi-use trail w/ramada Advantages: The intent of this park design was to allow the park to serve as a passive space while offering a dog park element towards the southeast corner. The plaza and parking were placed at the top of the retention basin with a play area, restroom and ramadas in close proximity while placing the three fenced, 1-acre, dog park zones at the bottom of the basin. By offering three fenced dog zones, turf could reestablish itself while that zone was closed for recovery, while the other zones were allowed to stay in operation. A multi-use trail wrapped around the entire site and was adorned with a ramada, ample trees, and lush landscaping. The design permitted an expansive grassy open green space for recreational activities and a buffer from the neighborhood as well. Disadvantages: This park design does not include a lake. Alternative C Primary Features (Figure 31): 30 to 35 feet wide concrete storm drainage channel 20-foot-wide earthen storm drainage channel ½- and 3-acre lake Boulder water feature Planned fire station 4-foot and 7-foot-deep retention basin (50- acre feet) to accommodate for a 100-year storm event Figure 31 52

9 Three 1-acre fenced dog park zones each with picnic ramadas and one with a beach for swimming dogs Ingress/egress off Sossaman Road Significant plaza with play area, restroom building and picnic ramada Multi-use trail with a group ramada and 3 picnic ramadas Advantages: The intent of this park design was to provide a lake element that everyone could enjoy as well as dogs. The park included a small ½-acre lake adjacent to a drainage weir where water would then travel down a boulder water feature to the 3-acre lake at the bottom of the retention basin. Three 1-acre fenced dog park zones, each equipped with a picnic ramada, granted ample room for dogs to run about, and one dog zone offered a dog beach for swimming. A weir wall was designed in the 3-acre lake to keep dogs from escaping from the park boundaries. A large plaza, adjacent to the parking lot, included a play area, restroom,and ramada. A multi-use trail wrapped around the site and included three picnic ramadas and one group ramada. There was a 1-acre east of the dog park zone that was designed to be a lush grassy open space to act as a buffer to the neighborhood to the east. was presented to the public for review and comments. The preferred alternative was then revised and developed into the Final Master Plan (Figure 32). Description of Primary Features: 30 to 35 feet wide concrete storm drainage channel 20-foot-wide earthen storm drainage channel 1.5-acre pond Expansive plaza including shaded play area, restroom building and picnic ramada (Figure 33) Three fenced dog park zones that average between 1.3 to 1.7 acres each and (1) ½-acre fenced dog beach zone with pier (Figure 34) Dog agility equipment Pump station for pond Water feature weir wall to contain dogs Multi-use trails Planned fire station Drainage weir 6-foot-deep retention basin (50-acre feet) Picnic ramadas in each dog park zone Disadvantages: The main disadvantage to this design was that visitors going to the dog park had to walk through one dog zone to get to another. Preferred Alternative Site Plan Through the combined efforts of the Committee and the planning team, a preferred alternative Cost Evaluation Figure 34 Figure 33 Cost evaluation was prepared using current industry cost standards based on present market conditions. Costs are subject to change (Figure 35). 53

10 Figure 32 54

11 Figure 35 55