1

Sewerage networks implementation in Romania, the current status and

development perspectives in the process of material selection – a

managerial view

Eugen Vitan*

ABSTRACT

This paper presents in the first part the current context of implementation of investments in Romanian

sewerage infrastructure and its trend, and in the next, after a review of methods used worldwide for

the choice of materials, summarizes a method proposed by researchers of Technical University of Cluj-

Napoca for the material selection of sewer pipes.

1. The current performance of investments in urban sewerage infrastructure and selection

methods of materials

1.1. Specific legislation regarding the insertion of sewerage tubes on national market,

national and community regulations in Romania

Regarding the insertion of construction products on the specific Romanian market, should be

mentioned that it is in accordance with European legislation transposed into national legislation

(Law no. 608/2001 regarding product conformity assessment). Therefore, for a construction product

to be placed on the Romanian market it must prove compliance with specific European Directives

by Declaration of Conformity and/or Certificate of Conformity and CE Mark of Conformity.

In this period is also operational EU Regulation No. 305/2011 of the European Parliament and of

the 9 March 2011 Council of laying down harmonized conditions for the marketing of

construction products and repealing Council Directive 89/106/EEC that delivers innovations in

both performance certification as well in basic construction requirements of any kind.

Also, for the cases mentioned in European legislation can be admitted products that are the subject

of certain National Technical Approvals (AT) or Europeans (ETA) for the period of time stipulated in

these documents.

For this period the national technical regulations, small in number, will be supplemented by

standards and community guides, mostly untranslated into Romanian.

Thereby, regarding the sewerage networks outside buildings, are active over 15 European

standards taken by the national standardization. For a more comprehensive look we recommend SR

EN 752-2008.

Field regulations refer to general design elements, execution and exploitation for rural sewerage

networks or for plastic pipes, providing a low support for designers [24].

In terms of performance indicators for public sewer service [54] they are focused on the

relationship between system operators and their customers, extent of networks and specific

consumption of electricity for pumping wastewater.

* Associate Prof. Dr. Eng. Eugen Vitan, Technical University of Cluj-Napoca, Faculty of Installations

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1.2. The size of sewerage systems in Romania and the expansions dynamic

At the end of 2012 in Romania only 43.5% of the population was connected to sewerage networks

according to [6] and the total length of sewerage network was 23 137.2 km, of which 19 088.4 Km

urban areas and 4049 Km rural areas. Synthetic situation according to [6] is presented in Table 1.

TAB. 1 Existing sewer network length and growth rate in the last three years

Year

Network length [Km] Period for the

execution of

networks

at the current

growth rate

[Years] Urban

Growth

rate

urban Rural

Growth

rate

rural Total

Annual

growth

rate

2009 18 368 2 586 20 953

33.16

2010 18 890 2.77% 3 087 16.24% 21 978 4.66%

2011 19 088 1.04% 4 049 23.75% 23 137 5.01%

721 1 463 2 184

Under these conditions, besides the rehabilitation, there is a process of expansion of sewerage

networks likely to take place over the next 20 years given the current expansion rate and its growth

opportunities in the years ahead.

For such work, the required investment is huge. For a simple evaluation, where we consider specific

length constant and sewerage works value only 200 Euro/m their value approaches five billion

Euro (yet it is evident that built density is much lower in rural areas and execution costs exceed 200

Euro/m for diameters larger than 250 mm).

In Table 2 is presented the evaluation of investment requirements. The evaluation purpose was not to

establish a more accurate value but to draw attention to the magnitude of investment required for this

type of work.

TAB. 2 Population served by sewerage networks and investment requirements evaluation

Stable

population

in 2011 *

Population

connected to

sewerage

networks

at 31.12.2011

Specific length,

sewerage

networks/stable

population

[m/person]

Length of

sewerage network

to be executed in

the coming years

[Km]

Value of sewerage

network to be executed

in the coming years

[Euro]

19 042 936 9 319 223 2.48 24 141

4 828 288 634

1.3. Responsibilities and duties regarding the financing, design, execution and exploitation of

sewerage networks in Romania

1.3.1. Responsibilities and difficulties of system owners

Sewerage systems may be owned by land owners developed for various purposes or local

administrations property, obviously the latter own majority of the Romanian sewerage systems.

Considering that the systems owners are also investors for the modernization and expansion

* According to RPL 2011 program of development / National Institute of Statistics

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works, national laws [67] assign to them the following responsibilities:

­ setting quality standards to be achieved through the design and execution based on

technical regulations and studies and investigations;

­ obtaining necessary agreements and approvals required by law, and building permit;

­ provide verification of projects by specialists, certified project inspectors;

­ provide verification of correct execution of construction works through the specialized

managers or specialized consulting economic agents, throughout the work;

­ proceeding in order to resolve nonconformities, defects occurred doing the works

execution and projects deficiencies;

­ to ensure the reception of construction works at the work completion and at the end of

warranty period;

­ writing the owner’s manual and handing it over to the proprietor;

­ expertise the constructions by certified technical experts, when for those constructions

are carried out works that could lead to the change of hypotheses of structural analysis.

While construction quality system is very close to the technologically advanced countries in the EU,

quickly taking over certain techniques and technologies, on the one hand, and political inertia on the

other hand, lead to a number of issues specific to public administration owners of sewage systems as

follows:

­ the administrative staff is politicized and generally unqualified for the job position;

­ technical information and professional training are insufficient, are not appreciated and

do not benefit to those who follow them except masters and even doctoral courses that

sometimes were subject to real political transactions;

­ strategic studies for the development of towns and counties PUG/PATJ are generally

conducted by architects and present public utilities as an irrelevant annex, without

consideration of alternatives, related to land, operator or economic potential of the area;

­ infrastructure investments are proposed considering frontage technical alternatives,

usually one version is proposed and then, another alternative is searched through small

changes applied to the first and under these circumstances financial projections and

calculation of financial/economic ratios have no relevance;

­ life cycle used in the financial projections summarize the economic life on accounting

regulations (depreciation period) or the recommended life cycle by the accessed

financing program, without using life cycle specified in the technical approvals or

manufacturers statements and under these conditions life cycle has no relevance to

economic analysis;

­ there is no prognosis about the necessary investments in the infrastructure considering

the life cycle simulation on the types of utilities and used materials;

­ the only criterion for the award of auctions for the execution of infrastructure works is

the price of the investment without any connection with life cycle, operating costs,

ecological indicators of investment or costs of decommissioning and post-use of

materials;

­ design tasks or the specifications for designers of infrastructure investment do not

contain requirements for materials analysis with established methods (LCC/LCA or

MCDA/MCDM), do not contain requests for the minimum software necessary for design

works, do not correlate documentations found in planning stage and generally,

administration does not accept external consultants to achieve these specifications /

design tasks;

­ cost and time it takes to realize the infrastructure projects are more understated and

designers can hardly meet the demands of local governments and usually lower prices

and terms required bring a strong quality discount;

­ surveying information databases (with few exceptions) and geotechnical for areas under

management are not available, nor created.

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1.3.2. Responsibilities and design problems

As contractors, design firms are from the private system and public procurement law is the same, so

design services are selected considering a single criterion, the price of services and, rarely, duration

of achievement.

Projects stages of achievement in Romania are covered in [73] and can be summarized as follows:

a. Technical and financial studies (feasibility study for new investments and technical

documentation for approval of intervention works for the expansion and upgrading works of existing

facilities);

b. Technical documentation for obtaining construction permits;

c. Technical project;

d. Details of execution;

e. Any change of the solutions contained in the earlier stages of design throughout

the works is done by construction site provisions.

Legal requirements for design work [67] are:

­ specifying within the project the category of significance of building;

­ ensuring through projects and manufacture aspects of quality appropriate level in

compliance with technical regulations and clauses;

­ presentation of developed projects before specialists - certified project inspectors,

established by the investor, and solving reported nonconformities and inconsistencies;

­ developing specifications, technical instructions for the execution of works, operation,

maintenance and repairs and, where appropriate, tracking project regarding constructions

time endurance and performing the documentation of post-use construction only at the

request of the owner;

­ establishment, by project, of execution phases defined for demand related works and

participation on the construction site to related quality checks;

­ determining how to treat defects in execution by the fault of the designer, at buildings

which must ensure the requisite quality and follow up of the site of the solutions adopted

after acquisition by specialists - certified project inspectors at the request of the investor;

­ participation in preparing technical book of construction and at the reception of work

executed.

Given the sudden transition from communist economy and demands at those based on economic

efficiency, specific to capitalist society, almost all central and district design institutes were

privatized by means of division of shares to employees (MEBO). This system privatization led in

most cases at bankruptcy or their fragmentation.

On the other hand EU technical regulations acquisition was done without translation, in many cases,

and deepening of foreign languages in academic technical education leaves much to be desired.

Given the current context, issues specific to the design are:

­ carry out the projects by independent engineers or by very small groups that do not

obtain the project approval through Internal Review Boards;

­ diversity of engineering specialties to make projects of this type, there are construction

engineers, water engineers, construction equipment, health and environmental engineers;

­ ambiguity of regulations on verification of projects, network designers usually provide

verification of their specialty sewage Is, B9 and A1 I and when there are pumping

stations and IE;

­ lack of a national standardized method for structural / static / resistance calculation. The

acquisition of standard EN 1295 was done without translation (at EU level there is no

general agreement on methods in 1295, UK is promoting as national annex a different

method through BS 9295:2010);

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­ lack of protection of buildings near the routes and correlation with other utilities;

­ lack of understanding of the importance of geotechnical and topographic studies for

sewage network projects. Sometimes these studies are missing and other times the

networks designer is not making available for geotechnician and surveyor necessary

technical specifications according to the requirements of the specific projects;

­ the use of old topographical plans or without OCPI visa;

­ handing over formally or not handing over at all the landmarks;

­ tubes material choice depending on the client request, the documentation available, the

existing trade ties and interests;

­ lack of choice of materials for this kind of work.

1.3.3. Responsibilities and issues of sewerage contractors

The contractors of water and sewer works are national private company or other EU member

states, sometimes associated to the community, cross selection phase under national law [66] in

which usually only criterion, for after technical and financial capability criteria, is the price.

Quality construction law requires the contractor the following:

­ investors notification of non-compliance and inconsistencies found in the projects, to be

resolved;

­ beginning construction only of the works authorized by law and only upon and in

accordance with the projects reviewed by certified experts;

­ ensuring the requisite quality level through its quality system designed and built by its

own staff, with certified construction managers;

­ convening factors that must participate in verification of work reached the stage of

execution and determining necessary conditions in order to obtain the agreement to

continue the works;

­ solving nonconformities, defects and inconsistencies encountered in the execution phase

only determined by the designer based solutions with the consent of the investor;

­ using in the execution of works only the products and processes covered by the project,

certified or for which there are technical agreements, that lead to requirements

achievement, and management of control samples; replacing products and processes

covered by the project with others that meet specified conditions and only on solutions

established by the designers with the consent of the investor;

­ compliance with projects and details of execution to achieve the requisite quality level;

­ notification within 24 hours, of State Inspections in Construction, public works, town

and country planning in case of technical accidents during construction;

­ submitting to reception only the construction that meet quality requirements an for which

were delivered to investor the necessary documents to draw up the construction technical

book;

­ to accomplish, within specified time limits, the measures imposed by the audit or by the

documents for construction work;

­ remedying at his own expense, qualitative defects arising from his fault both during

execution and during the warranty period established by law;

­ temporarily occupied lands restored to their original state on completion of the works;

­ establishing responsibilities of all participants in the production process - factors

responsible, employees, subcontractors - in accordance with its own quality assurance

system and with legal provisions in force.

Under these conditions the specific problems of sewerage executed works are:

­ insufficient knowledge of specific technical regulations for execution;

­ lack of geotechnical works phase. Geotechnical tracking of the works;

­ lack of specific procedures and instructions for sewer networks works (from Quality

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Management System);

­ failure of quality control steps;

­ lack of appropriate measures and measurements for compaction of the land filling and

achieving foundation for tubes;

­ lack of evidence of leak or performing it formally;

­ lack of control through CCTV systems at the reception of works;

­ tracing and tracking the inappropriate bottom trenches level and pipes foundation;

­ ignorance or failure to use the categories of land listed in the project in order to achieve

foundation for tubes or fillings;

­ lack of specialized personnel in pursuing of works (project supervisor).

1.3.4. Issues related to the exploitation / maintenance of sewerage networks:

­ lack of maintenance procedures and instructions;

­ lack of consumer chopping devices, coupled with the throwing of objects of wood,

metal, plastics, or clothes in the sewer system, resulting in deep scratches, clogging or

breakage of tubes;

­ lack of correlation between high pressure pump washing/jetting pressures and tubes

material;

­ often, the lack of a plan with the correct position of networks;

­ lack of hydraulic modelling to allow the approval of new flow takeover knowingly;

­ lack of evidence of defects, highlighting the causes;

­ lack of management of analytical operating expenses by types of tubes and stages of the

managed system;

1.4. Weaknesses of sewerage networks pipes in Romania

Given the issues raised in all sectors involved in sewerage projects can be mentioned the following

operational matters:

­ structural failure, clogging of pipes and system loss of tightness;

­ overcoming deformation (deflection) allowed for flexible tubes followed by changes in

transport capacity, separation of joints and possibly even structural failure;

­ structural failure due to corrosion;

­ longitudinal cracks for rigid pipes, followed by ground penetration into the tube and

structural failure;

­ clogging of tubes and their structural failure in exploitation operations;

­ peeling of composite tubes.

1.5. The choice of material for sewerage tubes in Romania

Existing technical regulations show objectives, requirements and partly material selection criteria

only, without presenting methods [37, 83, 84].

Designers, owners and operators of their sewer systems and government agencies with

responsibilities for control and guidance for municipal services, in the absence of comprehensive

national technical regulations, use either technical regulations of other countries (rare) or

instructions of manufacturers of sewer pipes (often).

In this case, the choice of sewerage tubes results implicitly, according to the design guidelines of the

design company or to informal feedback received from sewerage system operator.

Public acquisitions in Romania usually are assigned to lowest investment bidder and in this case are

preferred products whose purchase price is reduced without making an analysis of the lifetime

costs of material or an analysis of incompatibilities with site-specific chemical or biological

requirements.

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2. Community level trends

2.1. Requirements and technical regulations

Specific requirements of design activity historically evolved in stages defined as follows:

­ requirements on product function / object designed;

­ requirements on function and financial costs;

­ requirements regarding function, economic costs and energy consumption;

­ requirements regarding function, economic costs, energy consumption and

environmental costs (emissions of greenhouse gases);

­ requirements regarding function, economic costs, environmental costs and sustainability

of raw material consumption.

If in terms of hydraulics, construction, testing, management and verification of network things are

quite clear, in terms of structural design could not be found a consensus between versions German,

French and English.

In this situation arose SR EN 1295 - Structural design buried pipes, which shows the general

requirements but the sizing method that should occur as indicative EN 1292-3, has not taken

the form of a standard but only of a study recommended by CEN as CEN / TR 1292-3:2007,

showing French and German methods, while the English method is subject to a national standard BS

9295-2010.

However we can conclude that Community and national technical regulations that relate to design

focused on designed product/object are comprehensive and sufficient for designers of EU countries.

2.2. Existing methods for the materials selection

By now classical methods in choosing the materials are:

­ Least Cost (Life Cycle) Analysis;

­ Ashby methods for materials and process selection, developed by Granta Design in

collaboration with Professor Mike Ashby from University of Cambridge;

­ Multi-criteria decision analysis (MCDA), with many methods in use today, but the most

common are AHP, ANP, SAU / MAU and ELECTRE.

2.2.1. Life Cycle Analysis (LCC) is a method of adding the cost over the life of the project. In this

context the project means the design, execution, operation and post-use of materials used in the

project.

In [78] is showing computation recommended for adding the costs in the form below:

LCA=C – S+Σ(M+N+R) (1)

where:

C = original cost,

S = residual value,

M = maintenance cost,

N = rehabilitation cost,

R = direct and indirect replacement cost.

Indirect costs are costs related to traffic when sewerage networks are under roads.

By applying this method is chosen the material that leads to the lowest cost during the life cycle of the

project.

Modern methods of analysis of the life cycle of the materials that compose a product, in which

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besides cost analysis is performed and environmental analysis, are detailed in [49] and [52]. These

methods identify costs and environmental impact of the material life cycle by providing a hierarchy

of materials depending on the value of the parameters of the project's life cycle.

2.2.2. Ashby methods for materials and process selection

Materials selection methods described in [3] also covered by engineering research and educational

software products (CES EduPack) are intuitive and represent an important basis of engineered

reasoning for the process.

Therefore, of the methods described (Analysis, Synthesis, Similarity and Inspiration) method of

analysis (Analysis) is closest to the requirements of basic engineering.

Implementing such a method crosses the following steps:

­ defining the objectives and requirements of the product;

­ identification of measurable qualities of the product or determinable by calculation

that quantifies its performance;

­ identification of material properties that increase product performance;

­ achieving a screening of databases to identify the closest performance requirements.

­ potential to optimize the decision-making process by calculating product costs.

Database made available include about 3000 materials and the proposed selection methods can be

implemented using two advanced software instruments CES Selector and Eco Audit Tool.

2.2.3. Multi-criteria decision analysis (MCDA)

Sometimes called multi-criteria decision making (MCDM), is a discipline aimed at supporting

decision makers faced with making numerous and sometimes conflicting evaluations. MCDA aims

at highlighting these conflicts and deriving a way to come to a compromise in a transparent process

Application of these methods involves performing the following steps:

­ determining a large number of possible alternatives;

­ creation or acquisition of attributes / criteria that are applied to all alternatives identified;

­ allocation of values that reflect the share of each attribute / criterion in general.

­ There are many MCDA / MCDM methods in use today. Some of the MCDA methods

are:

− Analytic hierarchy process (AHP);

− PROMETHEE;

− ELECTRE;

− Analytic network process (ANP);

− Global Utility Method.

Method sensitivity is manifested by bias that characterizes usually the allocation of criteria and their

weight.

2.3. SSM engineering tool (based on Global utility method)

A. Safety

Starting from sewerage systems objectives (described in EN 752-2008 and Regulation EU No

305/2011, Annex I, of the European Parliament and of the Council of 9 March 2011 laying down

harmonized conditions for the marketing of construction products and repealing Council Directive

89/106/EEC) and considering the correlation between objectives and operational requirements

presented in the EN 752-2008 we have identified a number of material properties who meet the

requirements, and implicitly the targets.

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We've drawn up a table where properties of material gained weight in achieving the objectives

considering qualitative assessments from EN 752-2008. In a second table we introduced

material properties. We normalized material properties by determining the utility and we

determined the scores for each material considering the weight of material properties to achieve the

objectives and the value of material properties considered relevant.

For values of material properties was made a small database with reference to the original sources

(Annex 1).

B. Sustainability

For economic sustainability analysis we used the method Life Cycle Analysis / Cost (LCC) as

described in ASTM C 1131-10, Standard Practice for Least Cost (Life Cycle) Analysis of

Concrete Culvert, Storm Sewer, and Sanitary Sewer Systems.

In order to apply the method LCC we evaluated the execution works for one meter of sewage

network in different situations using computer software developed by Softmagazin.

For the analysis of environmental sustainability we considered relevant the indicators of

embodied energy and CO2 emission equivalent.

Also for sustainability objectives we used the same method of aggregation, the method of global

utility and additionally a score for each material.

C. Ranking table

The final table includes two categories of criteria, safety and sustainability with different weights

given by the project manager and with global utility relations included in spreadsheets we obtain the

hierarchy of the analyzed materials.

3. Conclusions

In conclusion we must say that, as a result of the exponential increase of consumption, the concern for

resources must increase and future technologies will undoubtedly allow to choose materials

considering the safety requirements only related to economic and ecologic sustainability.

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