Water quality

The checks on the quality of the drinking water supplied and of effluent returned to the environment, after the process of purification, are performed in a planned and constant manner by the companies of the water industrial area. The analyses on the drinking water distributed to users play an essential role for the resulting health spin-offs. A summary of the work carried out in this area, by all the water companies, is shown in Chart no. 45.

CHART NO. 45 - TESTS OF DRINKING WATER, TOTAL AND BY COMPANY (2018)

In Rome, the qualitative characteristics of the resource collected and distributed are monitored through continuous testing, with instruments located along the water systems and through daily sampling at the collectors and in the distribution network.
In Lazio there are areas of volcanic origin where the water has drinkability problems, linked to the natural presence of some substances in greater concentrations compared to those permitted by the relevant legislation. In these areas Acea Ato 2 has performed, over the years, a number of initiatives aimed at solving these problems, increasing the purification plants able to remove the unwanted substances and returning their values of concentration well below the legal limits.
Regular monitoring of the chemical/biological parameters of the water which circulates in the distribution network of the water system allows the quality safety level to be kept high.

Altogether about 359,491 ¹¹⁸ analytical tests in the territory of Ato 2, for a total of 10,708 samples – in addition to those of the Health Authority – were carried out during 2018 in the Grottarossa Laboratories, managed by Acea Elabori.

The analytical checks on the water and the relative measurements are also performed by Group companies independently.
The subsidiary Acea Elabori, accredited pursuant to the ISO/ IEC 17025 standard, performs and certifies chemical and physical and bacteriological analyses in different substrates, including water (see Table no. 53 for the analyses performed on Rome drinking water). Gesesa instead uses two outside laboratories (see the Environmental Accounts or the Gesesa data and also for the aggregate data).

[118] The data on analytical testing of drinking water from 2018 also include analyses on recently acquired aqueducts (Civitavecchia and others).

Table n. 53 - ANALYSES PERFORMED BY ACEA ELABORI ON DRINKING WATER - ROME HISTORICAL NETWORK (2016-2018) AND AVERAGE CHEMICAL AND MICROBIOLOGICAL PROPERTIES OF THE DRINKING WATER DISTRIBUTED AT ROME, THE MUNICIPALITIES OF ACEA ATO 5 AND BENEVENTO (2018)

ANALYSES PERFORMED BY ACEA ELABORI ON DRINKING WATER - ROME HISTORICAL NETWORK (2016-2018)
sampling area	no of sampling points	no of samples			no of analayses
	2018	2016	2017	2018	2016	2017	2018
collection	45	469	423	437	21,085	21,636	21,119
water system and water feed pipes	26	158	183	130	6,051	6,599	5,167
stanks/water centres	21	248	119	152	8,974	4,988	6,306
distribution networks	320	4,208	3,381	3,326	135,943	109,838	109,571
total	412	5,083	4,106	4,045	173,702	143,061	142,163

AVERAGE CHEMICAL AND MICROBIOLOGICAL PROPERTIES OF THE DRINKING WATER DISTRIBUTED AT ROME, THE MUNICIPALITIES OF ACEA ATO 5 AND BENEVENTO (2018)
parameters	unit of measurement	average value - Rome	average vlue - Acea Ato 5 municipalities	average value- Geresa (Pezzapiana site)	legal parametric value (Legislative Decree no.31/01)
turbidity	NTU	<0.5	0.9	0.51	no anomalous changes
temperature	C°	12.7	13.5	exempt (*)	not required
hydrogen ion concentration	unità di pH	7.4	7.3	7.5	>6.5 e < 9.5
celectrical conductivity	µS/cm a 20 °C	560	595	896	<2500
chlorides	mg/l Cl	6.6	5.9	46.8	<250
sulphates	mg/l SO₄	13.7	11.31	66	<250
calcium	mg/l Ca	100.6	115.9	exempt (*)	not required
magnesium	mg/l Mg	19.0	17.1	eexempt (*)	not required
sodium	mg/l Na	4.7	3.6	37.0	<200
potassium	mg/l K	2.0	1.23	exempt (*)	not required
hardness	°F	32.9	36	35.6	(**)
free residual chlorine	mg/l Cl₂	0.15	0.19	0.15	(***)
alkalinity	mg/l CaCO₃	435	358	exempt (*)	not required
calculated fixed residue	mg/l	408	426.7	612	(****)
nitrates	mg/l NO₃	3.5	3.8	37.9	<50
nitrites	mg/l NO₂	<0.05	0.1	<0.03	<0.50
ammonia	mg/l NH₄	<0.10	<0.1	exempt (*)	<0.50
fluorurides	mg/l F	0.14	0.15	0.5	<1.50
bicarbonates	mg/l HCO₃	400	463.3	exempt (*)	not required
total	mg/l C	0.58	0.53	exempt (*)	no anomalous changes
iron	µg/l Fe	11.8	16.1	<20	<200
copper	mg/l Cu	0.003	0.00	<0.01	<1.0
lead	µg/l Pb	0.4	0.3	2	<10
cadmium	µg/l Cd	<0.2	<0.2	<2.0	<5.0
chromium	µg/l Cr	<5.0	<5.0	<2.0	<50
nickel	µg/l Ni	<2.0	<0.2	<2.0	<20
manganese	µg/l Mn	0.4	3.1	<2.0	<50
arsenic	µg/l As	<1.0	2.9	exempt (*)	<10
vanadium	µg/l V	2.4	1.7	<2.0	<140
total trihalomethanes	µg/l	1.0	0.7	<0.9	<30
trichloroethylene	µg/l	<0.10	<0.10	<1.0	<10
tetrachloroethylene	µg/l	<0.10	<0.10	<1.0	<10
1.2 - dichloroethane	µg/l	<0.30	<0.30	<0.1	<3.0
benzene	µg/l	<0.10	<0.10	exempt (*)	<1.0
benzo (a) pyrene	μg/l	<0.003	<0.003	exempt (*)	<0.010
coliform bacteria at 37° C	MPN/100 ml	0	0	0	0
e. coli	MPN/100 ml	0	0	0	0
Enterococci	MPN/100 ml	0	0	0	0

(*) In accordance with Legislative Decree no. 31/01 and in agreement with the health authority, Gesesa is exempted from supplying the parameter
(**) Recommended values: 15-50° F - the lower limit applies to water subjected to softening or desalination treatment
(***) Recommended value 0.2 mg/l.
(****) Maximum value recommended: 1,500 mg/l.