Posts tagged Monrovia Station Streetscape

It is doubtful anyone in Los Angeles needs convincing about the near-record amount of rainfall that drenched the city this winter. In comparison to drought-stricken winters past – and according to the LA Almanac – Downtown Los Angeles has received approximately 17 inches of rainfall since December of 2016. That’s impressively almost 8 inches more than for the same period of time during a normal winter.

Just over a year ago, AHBE Lab examined three recently constructed AHBE projects, setting out to identify how each were responding to that year’s El Nino storm event. Today we revisit these three sites, curious about each of their performances during this winter’s unusually inclement conditions. Here is what we found:

Photo: Jennifer Salazar

Monrovia Station Square Transit Village
The Monrovia Station Square Transit Village project included streetscapes envisioned as a sustainable connection between the surrounding neighborhood to the station. The Chilopsis trees shown above are planted in infiltration flow-through planters along Pomona Avenue and have captured recent rainfall, a feature we credit for the healthy tree growth.

Infiltration planters along South Myrtle Avenue have grown in with the grasses, while large oak trees and taller groundcover plants have filled in the wide buffer between the sidewalk and the parking lot. Photo: Katherine Montgomery

Carex alma (Sturdy Sedge) and Muhlenbergia capillaris ‘Lenca’ (Regal Mist Pink Muhly) were grasses specifically chosen for this project, and they appear to have grown in to fill the planters. The Silva Cells installed adjacent to each street tree are topped with permeable pavers, the combination likely helping to increase the size of the trees with an increased amount of rainfall being delivered to the trees’ roots.


The rainwater fed creek running across Johnny Carson Park. Photo: Evan Mather

Johnny Carson Park
The plants in the now natural bottom stream continues to fill in at this ASLA Southern California Quality of Life award-winning project. Some areas still hold recent rainfall in the creek. Rainwater also appears to be flowing as designed into the restored creek, later to be infiltrated into the sand bottom or to empty into the L.A. River.  Various riparian Salix, scrub, and perennial species have grown vigorously adjacent to the stream channel, providing a more natural appearing edge to the restored stream. Ducks have also been spotted swimming in the standing pools of water between storms.

Photo: Wendy Chan

Torrance Stormwater Basin – Entradero Basin
Entradero Stormwater Basin is one of many detention basins in the City of Torrance that mitigates and cleans storm water runoff before it’s released into the Santa Monica Bay. This stormwater basin was integrated into an existing park with baseball fields and playgrounds, so it essentially became a recreational feature for the community park. The park has evolved into a lively and well frequented public space populated with the activity of little leaguers, children playing along the basin edge, water fowl, and residents exercising  along with their dogs in tow across the trails.

Photo: Wendy Chan

Thanks to the plenitude of rain this winter the basin is currently filled with water. A pair of geese, a family of ducks, and various others birds currently make the seasonal basin their home. The planting is filling in and working overtime to help clean the runoff water. A restoration ecologist helped AHBE develop a planting palette to correspond with the various levels of inundation along the sloped basin. For example Lupinus spp. and Salvia spp. were planted along the upper slope of the basin where plants are rarely inundated with water, while Frankenia salina inhabit the lower basin where plants are seasonally inundated during the rainy season.

Entradero Park. Photo: Wendy Chan

The Entradero Basin provides a natural system for storm water mitigation, but also provides residents trail opportunities to enjoy the basin as a natural feature in the park. The basin appears to be working wonderfully to clean pollutants from storm water runoff and recharge groundwater aquifers by permitting water to slowly infiltrate, while additionally providing habitat for surrounding wildlife – in its entirety, the project is an example of how green infrastructure can be integrated into a community.

This post was authored by Wendy Chan and Jennifer Salazar.

AHBE Lab has offered insights about the causes and effects of El Niño, both in its global influences and to our local Los Angeles environment. Yiran Wang’s 10 Things You Should Know About El Niño is a great primer about the global seasonal phenomena, while Gary Lai’s piece, Feast or Famine: Epic Drought to Epic El Niño connects the historical meteorological antecedents with this year’s El Niño.

Now for something more material and concrete: three AHBE projects have been under construction during the recent El Niño storms. Each project is designed with different features and techniques to incorporate sustainable stormwater best management practices (BMP), and showcase solutions faced while working during an unusually wet season here in Southern California:

Monrovia Station Streetscape
As an adjacent project to the Monrovia Gold Line Station, this project was to “demonstrate the healthy relationship between public space and sustainability” (Design Criteria Manual draft – 12/2013), alongside to provide infrastructure for stormwater management. The 1.3 miles of sidewalk around the station neighborhood are constructed from permeable pavers above Silva Cells.

Silva Cells are open-sided box frames engineered to keep soil available for street adjacent tree roots. Also, the street trees are planted in lowered curbside parkway swales that permit stormwater to flow into each planter directly from the street gutter using typical roadway grading. The storm water that flows into the parkways infiltrates into the ground, supporting native plants and street trees.


The biggest challenge faced during this season’s heavy rainstorms has been young, newly installed plants being washed away in the flow through parkways due to the intensity and length of the rainfall. Mitigation includes replacing washed out plants and temporarily blocking off the inlets from the street until the plants have stronger, more established roots. Though the Gold Line Station will not begin public operations until March 5, 2016, the streetscape has recently had its final landscape review.

Team members: Prime, IBI Design Group; Civil Engineer, CivilTec

Johnny Carson Park
A 17-acre public park in Burbank just north of the 210 Freeway, this project’s primary best management practice is the transformation of the Little Tujunga water channel that traverses the park from a concrete-lined creek into a destination water feature designed with an enhanced wildlife habitat, recreational access, and improved water quality.

During the storms, the concrete channel had been removed and had not yet been planted with restorative bank-stabilizing planting. This resulted in the erosion of the bottoms and sides of the exposed channel. Riparian stream bank plantings that are part of the design – such as brush mattresses – are being installed as quickly as is feasible in between storms to stabilize the creek sides. Brush mattresses are a living erosion control mat that is durable upon installation, and will increase in durability as it becomes rooted into the slopes of the stream. The park is scheduled to open in spring of 2016.

Team members: AHBE, Prime; California Watershed Engineering (CWE), Civil Engineers; Restoration Design Group, Stream Restoration


Torrance Storm Water Basins Enhancement Project
AHBE designers worked with the City of Torrance and civil engineers California Watershed Engineering (CWE) to cleanse and mitigate stormwater at 3 locations in the city.


The primary goal of the basins is to reduce exceedance of bacterial release into the Santa Monica Bay. The stormwater is retained, treated, and infiltrated into the ground, with excess released into the Santa Monica Bay. AHBE’s landscape design creates natural habitat, encouraging an increase of wildlife within the area. An outdoor classroom, positioned at the highest point of the area, provides an area to engage and educate local students as they learn about this stormwater treatment system and its benefits to the environment. The basins were opened to the public last autumn.

See the recent video Stormwater Basin Enhancement Program – Torrance CiriCABLE produced at the completion of the construction in September of 2015: