Griffin Park — the largest residential development yet south of the 120 Bypass — will turn 388 acres of farmland into 1,301 homes.

It will spike traffic on South Main Street, add 4,000 plus residents, and will help push Manteca High’s enrollment past the 2,000 mark.

When completed, just under half of the square mile bounded by Woodward Avenue, Main Street, Sedan Avenue and Union Road will have been converted from agricultural use to residential subdivisions.

Crews are now tearing out an almond orchard where the first phase of development will occur along South Main across from the intersection with Rina Drive that is named after the late Rina Brocchini who was part of a longtime Manteca-Ripon farm family.

Rina Drive will be extended westward to create one of five access points to the development from South Main Street. It is here that the first infrastructure will be put in place with a goal for the first homes to be built in mid-2021.

Based on current market conditions, the last homes in Griffin Park could be built as earl as by the end of 2026.

Project will further exacerbate problems

created by city’s failure to address South

Main from Bypass to Atherton Drive

While the design of Griffin Park will upgrade how neighborhoods are interconnected and will address a number of development issues that created problems elsewhere in Manteca include traffic movement on a major arterial adjacent to their project, what it will do in a negative fashion is expose the city’s failure to have an actual plan in place with a way to implement it rather than vague policy statements and lines on a map to upgrade one of the most notorious bottlenecks in the city — Main Street from the 120 Bypass to Atherton Drive.

The lack of a city action plan has been duly noted by Caltrans in their environmental work for the $54 million first phase of the 120 Bypass/Highway 99 upgrade project breaking ground next fall.

Caltrans pointed out that due to congestion issues on Main Street at the traffic signals, traffic routinely backs up into the outside eastbound lanes of the 120 Bypass during commute hours and other times of heavy travel. The city’s placement of an auxiliary lane from the Union Road to Main Street as part of the recently completed diverging diamond interchange work will help, but due to backups on the off ramp traffic will still end up stopped on the freeway where traffic often moves at 65 mph.

Traffic also will back up as far south as midway between Atherton Drive and Woodward Avenue waiting for the eastbound off ramp signal to allow vehicles to pass through. That in turn has led to traffic conditions normally only seen in Manteca at Main Street and Center Street where traffic will block Atherton Drive movements after signals have changed.

Two years ago the problem on northbound South Main was only during select time periods on weekends when residents south of the 120 Bypass ran errands or went shopping. Now it is a seven day a week problem and even occurs when commute traffic is returning to Manteca.

The city at some point in the coming years will use growth fees to install traffic signals at Woodward Avenue and Atherton Drive.

Assuming the city early next year follows through on the City Council’s promise to widen Main Street to four travel lanes through downtown, the overpass and the segment between the freeway and a point north of Atherton Drive will be the only remaining bottleneck on Main Street once the Griffin Park project is completed from Sedan Avenue to Lathrop Road.

Griffin Park will widen South

Main to four lanes to Sedan

That’s because Griffin Park is the first residential project where the developers have agreed to put in the full width of a major arterial that the neighborhood they are building where there is no development on the opposite side of the street.

When the first phase of Griffin Park gets underway and assuming right-of-way from adjoining properties are obtained, South Main Street will be widen enough to accommodate four lanes with a 14-foot wide landscaped median from South Main to Sedan Avenue. The only things that won’t go in on is on the far west side that are improvements beyond curb and gutter meaning sidewalks and landscaping won’t go in until adjoining land is developed.

Typically the city only requires builders to improve part of major streets to the center line that border the property they are developing. But in the case of Griffin Park three developers with Manteca roots — Raymus Homes, Manteca Development Group, and Atherton Homes — worked with the city in a bid to get the entire roadway widen to its ultimate configuration of 104 feet plus widen sections of the corridor not bordering their property.

The potential for South Main Street to go in as a 104-foot wide street before development occurs on both sides of the corridor is a departure from past practice. The way the city has allowed development to occur for years  led to bottlenecks or squeezes in various locations on major streets throughout the city that took years to be widened. There are number of instances where streets still haven’t been widened such as on Louise Avenue between Main Street and the Highway 99 overpass.

Two roundabouts coming on South Main

The project will also give Manteca its second and third roundabout on a major arterial.

Unlike the one on Louise Avenue west of Cottage Avenue, the two roundabouts will be built under ideal circumstances given there is no development currently at the two locations the city has required them — Sedan Avenue and the future alignment of Raymus Parkway.

That means the roundabout will be built in the middle of the alignment of streets feeding into it. And in the event the Raymus Parkway that will have a 104-foot width goes in as a four-lane road instead as an extremely wide two-lane boulevard, the roundabout at its intersection with South Main will be the city’s first roundabout where two four-lane streets cross.

Roundabouts move traffic more efficiently which in turn reduces air pollution from idling vehicles. It also slows traffic down and makes it easier for pedestrians to cross streets.

They also eliminate traffic signals that create ongoing expenses for cities to maintain.

The project also will create a roundabout where Raymus Parkway intersects with Tinnin Road.

The only other streets serving existing neighborhoods along South Main that will be extended westward into Griffin Park besides Rina Drive are Springfield Drive and Tannehill Drive. Legacy Street and Pear Street will not be extended cross Main Street.

There are also two access points to the overall development from Tinnin Road as well as one from Sedan Avenue.

There are six roundabouts planned on collector streets that will serve the interior of Griffin Park and access five distinct neighborhoods.

The developers have also agreed to resurface the segment of Tinnin Road just south of Woodward Avenue where a number of homes are found on less than an acre parcels. They decided to do that after it was determined some of the traffic leaving their development will use the segment of Tinnin Road that is still in the county’s jurisdiction.

New approach: Distinct neighborhoods

versus monolithic neighborhoods

The Griffin Park endeavor — an undertaking headed by local developers Toni Raymus, Bill Filios, Mike Atherton, Albert Boyce, and Daryll Quaresma — was originally planned for 1,592 homes.

It was scaled back to 1,301 homes by eliminating smaller lots that residents in nearby neighborhoods were objecting to in other projects submitted to the council three years ago hit approval snags.

Instead of being designed as a series of subdivisions for a monolithic development pattern, Griffin Park is envisioned as neighborhoods tied together with a series of linear parkways interconnecting four of the five planned parks as well as to bike lanes planned on Main Street. The fifth neighborhood park will have a linear parkway connecting it to the Main Street bike lane.

Griffin Park includes Manteca’s first estate-style neighborhood where all homes will be built on lots of 10,000 square feet or larger. 

The estate-style gated neighborhood may have as many as 88 homes and will be located in the southeastern portion of Griffin Park where the city’s long range vision calls for a transition to agricultural uses.

Most of the homes planned will consist of 4 to 7 homes per acre. That’s typical of the current development pattern south of the 120 Bypass.

Griffin Park is unaffected by the need for the cross-levee to provide state mandated 200-year flood protection. It is outside of the area that flooded in 1997. It is also outside the 500-year floodplain.

The also will be 65,340 square feet of commercial on the corner of the east-west collector street and South Main Street north of Sedan Avenue. The building design standards would require that they blend into the neighborhood much like Pleasanton required with commercial areas immediately south of the Alameda Fairgrounds on an arterial in that city.

A water analysis shows the current land uses — 261 acres of almonds, 45 acres of row crops, and 27 acres of small ranch-style properties — consume 1,686 acre feet of water a year. By contrast, the envisioned 1,301 homes, five parks, and greenbelts will use just over half that amount of water on an annual basis. The study noted Manteca’s sandy loam soil while fertile for crops does not hold water as well as other prime farm soils in the Central Valley. As a result, current irrigation practices such as sprinklers on a non-pressurized delivery system or flood irrigation requires more water to be effective in the growing of crops.

Students likely to attend

Nile Garden, Manteca High

The new neighborhoods will be in close proximity to three elementary schools — Woodward, Veritas, and Nile Garden.

Nile Garden, which is currently undergoing a $16.1 million modernization and expansion covered by Measure G bonds and growth fees collected on housing, is being expanded to accommodate 1,148 students based on space in place and being created for educational programs.

Given growth pressures near Veritas School and the fact another subdivision is preparing to break ground east of Woodward School where two other new neighborhoods are currently under construction, it is likely all of the Griffin Park students will end up going to Nile Garden School.

That may create issues given Manteca Unified has dropped to and from school buses except for special education students. It is just under a mile from the closest southern points of the 1,301-home projects to Nile Garden School.

If elementary students have to walk or bicycle they will do so along narrow Sedan Avenue, Tinnin Road, and Nile Avenue including a stretch where they will have to cross the high-speed and slightly wider Union Road as well as walk along Union Road for a short distance.

Manteca High as part of a $41 million modernization plan that included growth fees to build additional classrooms that will be able to accommodate high school students from Griffin Park.

Based on current home occupancy trends Griffin Park at build out could be home to just over 4,000 residents. Escalon’s population, by contrast, is 7,681 residents.

To contact Dennis Wyatt, email dwyatt@mantecabulletin.com