Review Reports - Changes in the Environmental Sustainability of the Urban Transport System when Introducing Paid Parking for Private Vehicles

Round 1

Reviewer 1 Report

“Changes in the environmental sustainability of the urban transport system when introducing paid parking for private vehicles”

Aim

The authors propose “a methodological approach to studying and assessing the environmental sustainability of the transport system of the city…A coefficient of environmental sustainability of the urban transport system and a formula for its calculation are proposed.”

Methodology

The approach follows standard traffic engineering practice where the road network is modelled by the VISSUM computer software with parking locations in the city centre identified and parking rates specified. The approach follows a classic urban transport planning processes whereby impacts of hypothetical parking charges per unit time (that increase the costs of using a private vehicle) alter modal choice in both the historical core of the city and across the city and the reduction in car travel (adjusting for speeds) reduces air pollutants (as documented in the accompanying tables and figures).

Evaluation

Superficially, the stated aims are broad and far reaching. However, when the manuscript is analysed the aims (as summarised above) are in fact narrow: in essence, the impact on modal share of paid parking.

There is a lot of extraneous information in the manuscript that tends to waffle around the meaning of sustainability and mobility as a service. It seems to the reviewer that a better structure of the paper is required: what is the problem? (this is covered by the fact that parking pricing policies have not been analysed in Russian cities? What is the relevant methodology? (this should come from a thorough review of the (parking) literature where it is noted that important references such as those of Todd Titman in Canada, Donald Shoup in the USA and William Young in Australia - amongst many authors – are missing) and why was VISSUM selected?

The manuscript is devoid of specific modelling elements and equations such as the mode choice model and the vehicle emission models for cars, trucks and buses. In standard engineering practice these are represented by equations with city-specific parameters. How were they calibrated?

More importantly, the authors state: “coefficients characterizing the additional resistance at the adjoining areas for the movement of individual transport were determined. The additional resistance takes into account: average time for using paid parking, average and median income of city residents, the cost of owning a personal car, the cost of using paid parking, and a number of other factors”. The meaning of “additional resistance” is not defined in quantitative terms and this needs further description as to how it is modelled because it is the authors claim in the abstract of originality.

This reviewer is highly experienced in 5 decades and is aware of very few scientific papers in English abour Russian cities. It would be good to include an overview (in the form of a table) of parking supply and charges in selected Russian cities.

The manuscript is clearly written but the sections often contain single sentences with no structured paragraphs but this is clearly corrected with careful editing.

Author Response

Thank you for the review. The corrected article and answers are attached in one file.

Firstly article then answers.

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 2 Report

The article proposes an evaluation of the effects of private vehicle parking pricing measures on the demand of transport in terms of redistribution of flows and modal split. A simulation model of the changes in air pollution from vehicles was used to assess the environmental sustainability of the transport system before and after the introduction of the abovementioned measures for car parking.

The topic is interesting and relevant especially in the time of climate change and COVID-19 which imposed more and more strict recommendations for the management and use of urban spaces and services.

However, I think the manuscript needs some improvements in order to be published.

1) in the Introduction the main topic, the assessment of the environmental sustainability of the transport system and the effect of indirect measures such as the introduction of limitations and payment for private car circulation and parking, needs to be better discussed citing previous studies and their pro and cons. Too few references are provided.

2) in “Materials and Methods” section the description of the simulation model used for this research is very brief and lacks details. For example, those concerning model settings, if reported, would enhance the quality of the work improving the readability, accuracy and replicability in other contexts. Also, a diagram representing factors involved in the model and their direct and indirect interactions would support the reader in better understanding methodological choices and steps. In other words, the provision of more precise information about the extent of the mutual effects among variables used in the simulation would improve give the text a more scientific sound in terms of precision, transparency and transferability. Without this information the methodological choices and parameters applied turn out to be arbitrary.

3) the “Results” section could be renamed “results and discussion” as it contains observation and comments about the model outcomes. I also suggest citing corresponding Tables in the text, systematically for ease legibility. Likewise, the contents of “Discussion” section are, in my opinion more pertaining to conclusions and should be shifted.

The text contains small oversights and needs to be revised.

Some minor recommendations:

rows 232-233 “because there is no need for large amounts of additional information for calculations”

I find the argument weak, it does not offer the reader convincing reasons for the methodological choice. Authors should try to reformulate the sentence in order to make the line of reasoning more understandable

rows 261-262 Verify corresponding Tables. Aren’t changes in demand described in Tables 3 and 4?

rows 279-281 and rows 289-290 Which table is it referred to?

rows 287-289 Was the implementation of paid parking measure in Moscow and S Petersburg used to calibrate the Tyumen model? If it is, I suggest shifting this sentence to the introduction of the simulation model by clarifying that empirical data used comes from these experiences.

rows 271-275 and 296-299 The provision of parameters used in the model would give accuracy and enhance legibility

rows 378-380 I suggest moving this sentence above in the paragraph when introducing results.